Spring Night, Omoda Seiju, 1930*
ROADSIDE CROSS
and a ditch on each side,
Two white butterflies
flit over the tall nettles.
stands a wooden cross.
Hung across the beams,
a crown of wildflowers
sways in the summer wind.
Silvering, the ghosts of flowers
tap lightly on the weathered wood,
as if knocking, asking
to be let in
into the Everlasting.
Now I speed on freeways,
sky-level interchanges.
Tell me, am I still
on the road to Damascus.
~ Oriana
A cross on fire, Warsaw. It's not known who set it on fire. The sight caused a storm of comments on social media, with some calling it a "beautiful sight," and others being appalled by that reaction.
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A POET OF SCIENCE WHO SHOOK FAITH IN GOD
Biographer Richard Holmes reveals how Tennyson predated Darwin and speaks to us today
When Richard Holmes was a fellow at Trinity College, Cambridge, in 2001, researching the surprising affinity among Romantic poets and scientists, he often walked by a giant white marble statue of Alfred Lord Tennyson, looking imposing and, well, irrelevant. Tennyson was the Victorian poet born after the wild Romantics, vaguely remembered by English senior citizens who had to memorize “The Charge of the Light Brigade” in school. “When can their glory fade?/O the wild charge they made!”
“With his long beard, Tennyson looked monolithic, like he had nothing to do with anything,” Holmes said to me recently, from his home in Norfolk, England. “Life had passed on.”
Being the natural-born biographer he was—Holmes had written vivid books about the poets Shelley and Coleridge—he began to wonder about the young man beneath the beard.
Who was Tennyson before he became England’s stodgy poet laureate? Holmes seemed to recall that Tennyson was tutored by another one of the marble statues in the chapel, William Whewell, a Cambridge don of science, who in the first decades of the 1800s published works on astronomy, physics, mineralogy, and philosophy. Perhaps science lurked in Tennyson’s background.
Holmes filed away the thought as he went on to write his 2008 book about the Romantic poets and scientists, The Age of Wonder, a brilliant corrective to the “two-cultures” trope that 19th-century science cut the heart out of humanity and the humanities.
The era’s radical poets—Byron, Shelley, Coleridge—read deeply in the burgeoning sciences of astronomy, chemistry, and electricity. The scientific revelations supercharged their poetry and amplified the natural world and the cosmos with astonishing beauty and terror.
The poets palled around with scientists like gregarious chemist Humphry Davy, whose experiments with dosing himself and volunteers with nitrous oxide formed a blueprint for anesthesia. Getting high on the gas was an “unmingled pleasure,” Coleridge said, echoing Xanadu, with its “stately pleasure dome,” in his poem “Kubla Khan.”
In London taverns with Coleridge and essayist Charles Lamb, anarchist philosopher William Godwin and his wife Mary Wollstonecraft, Davy loved to hold forth on the likeminded mission of science and art. The genius of Newton and Shakespeare are not remote in character, Davy would say. “Imagination, as well as the reason, is necessary to perfection in the philosophic mind.”
Holmes spoke with infectious enthusiasm for his subjects, as if they were old friends. “One of the most interesting exchanges that Coleridge and Davy had was on the idea of pain,” he told me. “What is the function of pain, particularly in animal life? What is it doing? Why was it put there? They would frame it in terms of, ‘Why did God put pain into this system?’ This was the kind of metaphysical discussion they often had.”
Crossing the wires of science and poetry sparked a dangerous new awareness. Through the eyepieces of the new telescopes, illuminating the vastness of space, Earth suddenly looked insignificant. Fossils of extinct species, uncovered in rock layers that had to be hundreds of thousands of years old, gave lie to the Bible story that God created all creatures great and small in six days. Religion was losing its hold on truth.
The complex feelings caused by the new revelations can’t be understated. Nature wasn’t as people had been told—it was more extraordinary! The Romantic poets captured the vertigo of a worldview caving in, and a new one evolving. And their poems were widely read. As a kaleidoscope of images from astronomy, chemistry, and geology, Romantic poetry was the first popular science.
After The Age of Wonder was published, Holmes wrote about the adventures and scientific discoveries (the layered spheres of Earth’s climate system) of the first hot-air ballooners, and candid reflections on his experiences as a biographer, the Frankenstein art of bringing the dead alive. But he knew the story of science and poetry couldn’t have ended with the Romantics and began to think about the next chapter. He didn’t have to think long. His curiosity about Tennyson returned. He decided to chip away the marble statue and meet the real man underneath.
Tennyson was born in 1809, the same year as Charles Darwin and Edgar Allan Poe. He came of age in a chaotic family of 11 in the country parish of Somersby in England. His father was the parish’s highly educated rector who carried a chip on his shoulder for being left out of his family inheritance for being “rude and ungovernable” as a kid.
To escape his father’s drunken rages, Tennyson journeyed to the seaside town of Mablethorpe and strolled along the windy dunes and beaches on the North Sea. “I come again,” he wrote in a poem: “Gray sand-banks, and pale sunsets, dreary wind, Dim shores, dense rains, and heavy-clouded sea.” Not the cheeriest of chaps, that Tennyson.
At Cambridge, Tennyson often hid behind his sullen self. At the same time, Holmes would write, the budding poet was “strange, energetic, independent, and subtly engaged with contemporary questions” arising from the daring science offending the Christians in his midst. Tennyson read through works on astronomy, geology, and the incipient science of evolution with his mind ablaze.
Holmes grew up farther south in Kent County. In his early teens, following his own wandering spirit, he and his older sister rode their bikes a couple hundred miles north to camp on the dunes along the North Sea beaches. Holmes hadn’t returned for decades when in 2020, deep into his research on Tennyson, with England under lockdown during the dreary Covid days, he had the freeing idea to make like the poet and return to the gray sand banks and wander under pale sunsets himself.
“The North Sea coast is quite fierce, and always meant rather a lot to me,” Holmes said. “It was wonderful returning there. I felt Tennyson’s childhood excitement as my own. Coming back to the atmosphere of that wild North Sea coast was quite another level of inspiration. It was like returning to my old idea to go and walk in the footsteps of people to write about them.”
Holmes’ reference is to his 1985 book Footsteps, which trailblazed a new model for the literary biography as autobiography, and travel writing too. Holmes’ own life and passions emerge as he traces the footsteps of his young idols, including Robert Louis Stevenson, Wollstonecraft, and publicly flamboyant Romantic French poet Gerard de Nerval, best known (if at all), for walking through the gardens of Paris with a lobster on a leash.
After his drives to the North Sea coast in 2020, Holmes felt a newfound closeness to Tennyson. Discovering Tennyson’s engagement with science deepened the connection. Through Tennyson’s eyes, Holmes thought, he could portray the social earthquake of science in the Victorian era—and take readers with him. Which he has done beautifully in The Boundless Deep: Young Tennyson, Science, and the Crisis of Belief, published earlier this year.
Tennyson is an ideal lens on the insurrections of science because his brooding nature made him so incredibly sensitive. His father’s violent outbursts not only cracked apart the family—two of Tennyson’s siblings were confined to a mental asylum—but Tennyson’s faith.
“Because of the nature of what we’d now call a dysfunctional family,” Holmes said, “Tennyson, despite his golden education, became a kind of permanent outsider. That allowed him to take on board all these rather frightening things about science, to educate himself and write about them.”
If Tennyson was a saturnine fellow by nature, he sunk even deeper into his tenebrous self when his closest friend, Arthur Hallam, died of a stroke at age 22. Tennyson and Hallam trekked across the mountains and villages of Europe together, sharing the kind of conversations that you can only have once in your life, the kind that liberates you from yourself, allowing you to feel what love is.
Hallam’s death haunted Tennyson nearly every waking and sleeping hour. For 16 years, from 1833 to 1849, he wrote about his friend, a “fragmented graveyard,” Holmes writes. In total, Tennyson wrote 131 cantos, published together as “In Memoriam.”
The intensely autobiographical work opens with one elegy of pain after another. But gradually a transformation takes place. Hallam’s death leads Tennyson to consider “death in general, and the meaning of ‘Extinction’ throughout nature.” These reflections stemmed from his reading in science.
One work that had a profound influence on Tennyson was Principles of Geology by Charles Lyell. In it, Tennyson read, “Amidst the vicissitude of the earth’s surface, species cannot be immortal, but must perish, one after another, like the individuals which compose them. There is no possibility of escaping from this conclusion … None of the works of a mortal being can be eternal.”
“It’s difficult to appreciate today what a bewildering impact this would have had back then,” Holmes said. “Here was evidence that individual animals, creatures, had become extinct. From that came the logical idea that mankind itself was destined to become extinct.”
In his epic mourning for his beloved friend, Tennyson transformed Lyell’s science into mourning for the cruelty of nature, a decade before Darwin published On the Origin of Species. Before Tennyson or anyone could have read Darwin, Holmes explained, Tennyson captured “the metaphysical crisis that Darwinism and the actual theory of evolution would subsequently produce throughout society.” In fact, Tennyson penned one of the most famous lines about nature—“red in tooth and claw”—often mistaken for something Darwin wrote. A stanza of “In Memoriam” goes like this:
Tennyson uses “ravine” in its Victorian sense of rapine or plundering; in other words, God’s love is fine and all, but no match for nature’s violence.
“That phrase, ‘red in tooth and claw with ravine,’ would have struck Tennyson’s original readers with horror,” Holmes said. And not just readers in elitist academies. “In Memoriam” was published in May of 1850; by the end of that year, it had sold 60,000 copies. That number, unheard of for a book of poetry today, made “In Memoriam” the talk of English towns.
Many biographies and books of criticism have been written about Tennyson since the poet’s death in 1892. What’s exceptional about The Boundless Deep is how modern that Holmes makes Tennyson feel. In one of his youthful conversations with Hallam, Holmes writes, Tennyson told “a story about a Brahmin destroying a microscope because it showed animals killing each other in a drop of water. He and Hallam agreed that this was a ‘significant’ kind of unscientific response: ‘as if we could destroy facts by refusing to see them.’”'
Tennyson’s relevance today “is not so much about science itself, but what science does to the human imagination,” Holmes said. “That was Tennyson’s subject. Science shares things that we can’t face but have to face. We still undergo the same emotions today. Science can haunt and depress. But it can also expand and excite.”
In a poem Tennyson began in the 1830s, “The Palace of Art,” he imagines a woman astronomer describing what she sees through a telescope.
Edwin Hubble, the 20th-century astronomer who established that galaxies exist far beyond our own, planting awe in humanity’s conception of the universe, wrote, “Our stellar system is a swarm of stars isolated in space. It drifts through the universe as a swarm of bees drift through the summer air.”
“I don’t know if Hubble read Tennyson,” Holmes said. “But isn’t the image of the universe as a swarm of bees wonderful?” Yes, it is.
In The Boundless Deep, Holmes has done what science does. He has stripped away myths calcified in culture to expose what’s real. Tennyson is not the stodgy marble statue anchored in the Trinity Chapel at the University of Cambridge. He was and is a magnificent voice of humanity and the universe, ringing out today.
https://nautil.us/a-poet-of-science-who-shook-faith-in-god-1279489?utm_source=firefox-newtab-en-us
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The very first story submitted for the very first seminar I ever conducted in the Creative Writing program/English Department of a large Midwestern university in the capacity of a visiting assistant professor, some 35 years ago — my very first "real" teaching job in the US — opened with this sentence: "In the twilight of his life, pushing forty, John finally realized that his whole life had been one huge mistake.” ~ M. Iossel, Facebook
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"Why did you live? Why did you suffer? Surely all of this is just a huge and terrifying joke? I give my answer in the final movement.” – Mahler, on his second symphony, the Resurrection (~From the Facebook page of M. Iossel)
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’FUND PEOPLE, NOT BOMBS’: INSIDE THE US MOVEMENT AGAINST WAR IN IRAN
A protest against the war in the Middle East outside the offices of Chuck Schumer in New York on Monday.
On Monday afternoon, dozens of people sat down in front of the New York senator Kirsten Gillibrand’s Manhattan office. Shedding their casual-business attire, they revealed matching shirts that read “FUND PEOPLE, NOT BOMBS”.
They were some of hundreds of protesters – including Chelsea Manning, actor Hannah Einbinder and artist Molly Crabapple – to tell Gillibrand and the Senate minority leader Chuck Schumer that they disapprove of the US sending more weapons to Israel, as the two countries wage wars in Iran, Lebanon and Palestine.
Nearly a hundred protesters, including Manning, actor Hari Nef and New York congressional candidate Darializa Avila Chevalier, were arrested after the group shut down traffic on Third Avenue.
The action, coordinated by Jewish Voice for Peace, About Face: Veterans Against the War and several other groups, called on the senators to back a vote on joint resolutions of disapproval, introduced by the senator Bernie Sanders in March, to block sending hundreds of millions of dollars in bombs and bulldozers to Israel.
This is the fourth such vote; Schumer and Gillibrand have held out in the past. Another war powers resolution vote, which affects not just war on Middle East states but potential warfare against Venezuela, Cuba or Greenland, is also set for Wednesday.
Monday’s protest was one of hundreds across the United States – and around the world, including in Israel – against US war-making in the weeks since Trump and Israel’s war on Iran began. At the No Kings protests in late March, countless protesters held signs or chanted about the bombings on Iran. In recent months, protesters have consistently questioned the ballooning US funds put toward war amid the administration’s deportation spree, federal funding cuts to public benefits, civil rights rollbacks for immigrants and LBGTQ+ people, unprecedented income inequality and attacks on Palestine.
“New Yorkers are sick and tired of hearing that there’s not enough money for their childcare, their healthcare, and yet every day we wake up and watch billions of dollars being spent on slaughter,” said Chevalier, who has organized in the city around immigration and Palestine, at Monday’s protest.
Polling backs that up: the war is measurably unpopular, hovering at roughly 50% of people opposed since its start; many voters lack confidence in the president’s approach to Iran, doubting he has a plan to bring the conflict to an end.
“The phones in Congress were ringing off the hook when the US went to war with Iran,” said Bridget Moix, general secretary of the Friends Committee on National Legislation (FCNL), which is aligned with Quaker values of pacifism. On Tuesday, FCNL hosted hundreds of people from across the country for a lobby day on Capitol Hill, calling for “No War at Home or Abroad”.
Though the vote on joint resolutions of disapproval is unlikely to succeed, according to organizers, they hope to pressure Democratic holdouts to connect funding Israel’s arms sales to the unpopularity of the war on Iran.
Many election postmortems established that Democrats lost credibility with voters in the 2024 election because of Joe Biden and Kamala Harris’s support for Israel. According to a memo shared last week with Democratic National Committee members citing recent polling from Data for Progress and the Institute for Middle East Understanding (IMEU) Policy Project, if Democratic leadership refuses to stand strongly against American war-making, including alongside Israel, they risk losses in future races.
Republicans face backlash for failing to come out adequately against the war and providing weapons to Israel, IMEU Policy Project communications director Hamid Bendaas said.
“Trump 2024 voters – which, yes, is Republicans, but it’s also right-leaning independents, irregular voters, people who might have voted for Biden in 2020 and then flipped to Trump, especially among young men – that’s the coalition that they would need to hold together to succeed in November and in 2028 as well, and I think that has completely shattered by this war,” Bendaas said.
Moix and Bendaas compared current anti-war sentiment to the era of the war in Iraq – and how that has drastically shifted in hindsight. “Many members of Congress came around and regretted their votes for [the Iraq] war,” said Moix.
Recent acts of civil disobedience have not been restricted to targeting elected officials on particular legislative efforts. The joint resolutions of disapproval and war powers resolution votes are scheduled for tax day in the US, where there is increasing interest in withholding income tax to protest government spending on war or federal immigration enforcement – a longtime form of anti-war resistance.
For Nef, Monday’s action was the first time she risked arrest. “I think you have to do a lot of mental gymnastics these days not to feel absolutely insane about what’s happening geopolitically,” she said. “Putting your body on the line is the most powerful articulation of your beliefs, and that’s what I’m willing to do today.”
https://www.theguardian.com/us-news/2026/apr/15/anti-war-protest-iran
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DAD BRAINS: HOW FATHERHOOD REWIRES THE MALE MIND
From before their babies are born, men undergo serious hormonal changes that can powerfully influence their behavior – with consequences for their child's wellbeing.
In the months before my son was born, my partner and I attended an active birth workshop, a breastfeeding session and the hospital-run antenatal course, read a small pile of pregnancy and baby books and scrolled through loads of websites. Our notepads quickly filled up.
Among my notes of that time are details of the many ways women's bodies prepare for birth and motherhood: hormones rise and drop, organs move, brains reshape.
No one, however, told me that my brain and body were also readying for fatherhood.
My son was over a year old when I first came across that idea in Father Time, a book by primatologist Sarah Blaffer Hrdy in which she argues that men have all the necessary biological wiring to be "every bit as protective and nurturing as the most committed mother".
This piqued my curiosity. I am a resolute believer in active fathering, but I had imagined this was a cultural decision by my generation of men. Hrdy's book, however, introduced me to an entire academic field saying that our approach is rooted in biology, just dormant and waiting to be triggered.
After interviewing Hrdy and other experts and delving into the studies, I came to a simple conclusion: fatherhood changes men in ways that echo how motherhood transforms women.
The more involved a father is with their baby's care, the deeper this transition becomes. These shifts in our endocrine and neural system show that the nurturing father is not a modern aberration, but a deeply rooted biological trait.
Falling testosterone
The earliest research on how fathers are physically changed by babies came from observations of other animals. These late 20th-Century studies found that many mammalian males – including other primates – show clear hormonal shifts, including rises and drops in hormones like testosterone, vasopressin and prolactin, typically associated with motherhood, as they engage in active parental care.
When the American anthropologist Lee Gettler, then an undergrad student, heard about these findings in the early 2000s, he was hooked.
"I asked [my lecturer] whether anyone was studying these questions in human fathers, and the answer at that point was largely no", says Gettler, now the director of the Hormones, Health, and Human Behavior Laboratory at the University of Notre Dame in Indiana.
The first-ever study demonstrating hormonal changes in men had just been published in 2000 by two Canadian scholars – Katherine Wynne-Edwards and Anne Storey. By the time Gettler looked into this field, it was already an established fact that fathers had lower testosterone that men without kids.
"But there's a chicken and the egg problem there, right?" Gettler explained to me. "Are low testosterone men more likely to become fathers? Or does the transition to fatherhood kind of lead to this cascade of biological changes in men?”
To answer this question and others, Gettler teamed up with the scientists running a decades-long project in Cebu City, Philippines.
In 2005, this team collected saliva samples from 624 men, with an average age of 21 years old and without partners, and tested them for testosterone, then four years later tested them again.
They wanted to answer two questions: would men who become fathers in the interim have lower testosterone, and would it be even lower in fathers that spent more hours doing childcare?
When the results came back, the answer to both questions was "yes". The men that had babies showed significantly lower levels of testosterone compared to non-fathers. And the men that had spent longer looking after babies showed the largest drops in testosterone. Those who shared a bed with their infants also had lower levels.
"I think it was the first clear message in the scientific literature that men have this capacity to prepare for fatherhood," Gettler told me. In a way, he explains, this is their biology preparing them for caregiving.
Their findings are not unique. Other teams have also found that drops in testosterone during their partner's pregnancy are also linked with higher investment, commitment and satisfaction after birth, and that this hormone’s level was even linked to the men's reactions to baby cries: it made them more alert and responsive. In 2018, a team in Gettler's lab also concluded that fathers with lower levels of testosterone tend to be more involved in caring for babies and toddlers.
But when does this happen? The question of whether it's before or after birth was bubbling in the mind of James K Rilling, the director of the Laboratory for Human Social Neuroscience at Emory University in the US.
"My assumption," Rilling told me, "was that it would happen during the postnatal period after fathers spent some time interacting with their infants.”
What they found surprised them. When they tested expectant fathers only four months after conception, two hormones were already lower than in their control group: testosterone and vasopressin. "And what's interesting is that the lower their testosterone, the more involved they become with the mother and infant postnatally," says Rilling, who in 2024 published Father Nature, a book exploring the science of fatherhood. He said vasopressin had a similar effect.
Rilling is intrigued about why this happens. Is there a pheromonal cue that fathers-to-be get from their pregnant partners? Is it a psychological shift once they know they are expecting a baby? As with many surprising findings in this relatively young field, we do not know. What is certain is that the changes go beyond testosterone.
A wave of the love hormone
Take, for instance, oxytocin, the so-called love hormone. This is one hormone I recall from my prenatal courses: we were encouraged to keep things relaxed and smooth during labor so my partner's oxytocin would flow and ease up the delivery.
Once my son was born, we were told, a huge surge of oxytocin at birth and repeated boosts through breastfeeding would help him and my partner bond. But I wasn't aware that in the first hours after his birth, as he napped on my naked chest, oxytocin was also rising in me.
Many studies around the world have found higher oxytocin in fathers, including those with kids aged one to two years old and those interacting with babies under six months – and that seems to correspond to the amount of time spent with our kids.
For instance, fathers that engaged in more playful games and contact with their children showed a rise in oxytocin, and a similar change was even evident when the fathers first held their newborns.
Oxytocin supercharges our paternal instinct. You can test this, Rilling explains, by spraying men's noses with the hormone and taking note of what happens.
"There's this one study I absolutely love," he says. "They give [dads] intranasal oxytocin as they are interacting with their infant, and they find that it makes the fathers move their head around faster." In the videocall, Rilling jolts his head from left to right and up and down, in what looks like a very convincing overexcited dad.
Such results suggest a positive self-reinforcing loop with oxytocin: as the hormone rises, a dad is more likely to engage with their child, which then triggers a further rise.
The more scientists look into this topic, the more changes they find in other hormones too. In a study published in 2025, Rilling and his team found that vasopressin – a hormone that in animals is often involved in territoriality and male-male aggression – was suppressed in new fathers before their babies were born.
Another surprising candidate is prolactin. In humans, this chemical is best known for its role in lactation and maternal care, but biologists have linked it with paternal care in other animals, including birds, fish and marmosets, a South American monkey known for its paternal instinct.
In 2023, a team led by American clinical psychologist Darby Saxbe looked at prolactin levels in expectant fathers and concluded that those who felt stronger bonds to their unborn child and that pre-birth prolactin levels predicted how involved these fathers would be in their care.
As we have already seen with the levels of oxytocin, both of these hormonal changes are more pronounced in dads taking greater care of their babies. "It's not the case that only new moms can be hormonal", says Darbe. "It looks like men are showing some of the same kinds of adaptations and some of the same kinds of consequences."
A second adolescence
Saxbe has been investigating whether the consequences of these hormonal shifts leave their marks on dads' brains. "I thought fathers are actually a very interesting, almost a special population in the sense that they experience the transformations of parenthood without biological pregnancy," she told me.
Birthing mothers get a blast of hormones while carrying their children and then get another boost at childbirth. But their partner's experiences are more subtle. "So they almost allow us to disaggregate the effects of pregnancy from the effects of parenting experience," explained Saxbe, whose book Dad Brain is coming out this 2026.
A few years ago, her team joined forces with colleagues in Spain to scan the brains of first-time fathers before and after their children were born. They discovered that there were neural changes underway. Their brains were adapting to adjust to new experiences and information.
Saxbe compares this transition into fatherhood with adolescence, another critical window of development in which our brain needs to adapt to new challenges, stimuli and ideas. And in a follow up study, she discovered that men who felt a greater bond with their unborn baby or planned to take more parental leave had larger changes in their brain. In 2026, Rilling reported similar evidence of brain changes in new fathers, confirming the neurological transition.
As for many of the changes in our paternal brains and bodies, there's a use it or lose it aspect: the more involved you get, the more you change. "It's just like something is triggered," says Sarah Hrdy, the primatologist who wrote Father Time.
She believes that all human brains have the latent capacity to parent, what she calls an "alloparental substrate", which can be activated under the right circumstances.
Contrary to some stereotypes, men may be biologically programmed for childcare
In Father Time, she argues that as humans evolved into more complex societies, it was collective care that made humans flourish. It was valuable to have men that could provide primary care for a baby, and so we developed a capacity to do so – one we still keep.
"Mother Nature is an old lady with some very bad habits," she tells me. "And a very thrifty housekeeper. When she has an ingredient that she is not immediately using, she doesn't throw it away. She stashes it in her cupboard."
These "stashed ingredients" come through in a 2014 study that Hrdy calls "one of the most exciting papers in science I'd ever read".
In it, a team of Israeli academics led by Ruth Feldman recruited heterosexual couples in which a woman provided primary care and the dad "helped", as well as gay couples raising kids without a woman involved, and scanned their brains while they watched videos of their babies.
For the straight couples, the brains of women doing primary care lit in areas related to deeper instinctual responses, such as the amygdala, while the men supporting them had more activity in social areas – that might imply they were first assessing a situation before acting.
But gay men who were giving primary care showed very similar activity in the amygdala and other "maternal" regions of the brain, while keeping the social element too.
Fatherhood was literally rewiring their brains.
Social shifts
All the experts I talked with, and the vast majority of the literature in this field, agreed that these developments in paternal biology should refocus public policy about families.
"It's an urgent societal priority that we shore up dads' opportunity to build those connections," says Saxbe. She says that improved parental leave policies, for instance, can facilitate the bond between dads and children.
Another key change is getting men involved from the outset, Gettler told me, including by attending ultrasounds, going to appointments and actively interacting with their partner during their pregnancy.
"We know that this biology is potentially coming online during the pregnancy period as families are preparing to welcome their babies," he told me.
Active, involved fathers have benefits for the family. Mothers with more active partners have reported better mental health in many countries including Pakistan, Kenya and the US.
And crucially, the children benefit too. In a huge study that followed 292 families over seven years and was published in early 2026, researchers from the US concluded that children of more attentive fathers had better heart health. The twist: mothers' behavior didn't have the same effect.
"I think there's a place for thinking about how the biology of fatherhood provides a foundation for structuring strong and healthy families from the outset," said Gettler.
https://www.bbc.com/future/article/20260417-fatherhood-how-the-male-brain-and-body-prepare-for-childcare
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ARTEMIS 2 AND THE FUTURE LUNAR LANDING
Nasa's Artemis II mission has passed every major test since its launch on 1 April, with its rocket, spacecraft and crew performing better than engineers had dared to hope for.
The mission's first six days have shown that the Orion capsule works as designed with people on board for the first time — something no simulator could prove.
Perhaps its greatest achievement, though, is through the actions of the Artemis crew, which have generated hope, agency and optimism for a world appearing to be in desperate need of inspiration.
But the bigger question remains — is a Moon landing by 2028, as Nasa and President Trump want, now really an achievable goal?
What Artemis II has taught us so far
A few days after Nasa's Space Launch System (SLS) reached the launch pad at Kennedy Space Center, the most important lesson about Artemis II had already been learned.
After two scrubbed launches in February and again in March because of separate technical issues, Nasa Administrator Jared Isaacman said "launching a rocket as important and as complex as SLS every three years is not a path to success."
The previous uncrewed Artemis I mission took off in November 2022.
The agency, he said, had to stop treating each rocket "like a work of art" and start launching with the frequency of a program that means serious business.
It was, in effect, a declaration that relearning the same lessons every three years had to stop.
That matters, because it reframes everything that has followed. And judged against that ambition, what has the mission shown us in the six days since Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen lifted off on April 1st?
The short answer is more than even the optimists dared hope for.
A Rocket that did the job
The SLS generated 8.8 million pounds of thrust at liftoff and, by every measure engineers care about, performed to plan. Each phase of the ascent was, in the understated language of mission control, "nominal": maximum dynamic pressure, main engine cut-off and booster separation.
Two of the three planned course corrections on the way to the Moon were scrapped because the trajectory was already so accurate they were not needed. As Dr Simeon Barber, space scientist at the Open University, put it: "Credit to them — they got it right the first time."
A day after launch came the critical moment. Orion fired its main engine for five minutes and fifty five seconds — known as the translunar injection burn — putting the spacecraft on a looping path to the Moon with no further major maneuvers required.
The powerful engine burn was "flawless" according to the head of the Artemis program, Dr Lori Glaze.
Humans in the machine
The official purpose of this mission is to put people inside Orion and find out what happens — not just to the spacecraft, but to the interaction between crew and machine. What has unfolded is precisely what was anticipated, and precisely what could not have been learned in a simulator.
There have been toilet problems. A water dispenser issue requiring the crew to bag water as a precaution. A minor redundancy loss in one of the helium systems was mentioned at an early press conference and quietly resolved.
As Barber observed: "This is all about putting humans in the loop — these pesky humans that press buttons and breathe carbon dioxide and want air conditioning and want to use the toilet. It was all about how the system works with those guys on board."
The engineers monitoring Orion's CO2 removal system through back-to-back exercise sessions, or testing how the spacecraft handles with thrusters deliberately disabled, are building the case that this vehicle is safe enough to carry people to the surface of the Moon.
Barber's overall assessment was direct: "Orion itself seems to have worked pretty well, actually — certainly all the propulsion stuff, which is the real critical stuff."
Great science or Nasa hype?
NASA has talked up the scientific returns. The crew made extensive observations during their flyby — around 35 geological features noted in real time, color variations that could reveal mineral composition, and a solar eclipse from deep space that pilot Victor Glover said "just looks unreal."
One image stood out: the Orientale basin, a 600-mile crater near the Moon's far side, seen in full by human eyes for the first time.
The Orientale Basin (or Mare Orientale) is one of the most striking and best-preserved impact features on the Moon, famously resembling a massive bullseye. Located on the Moon's extreme western edge, it straddles the boundary between the near and far sides, making it nearly impossible to see in full from Earth.
And yet the science is not the main point. Professor Chris Lintott of Oxford, co-host of The Sky at Night, was blunt: "The artistic value of the images returned from Artemis and its crew is significant, but their scientific value is limited."
India's Chandrayaan-3 landed near the south pole in 2023. China's Chang'e-6 retrieved samples from the far side in 2024. Robotic probes have mapped this terrain in extraordinary detail.
The most affecting moment came not from any instrument, but from the crew. As the astronauts broke the distance record set by the stricken Apollo 13 crew in 1970, Mission Specialist Jeremy Hansen called down to Mission Control in Houston.
There was a crater, he said, on the nearside-farside boundary — a bright spot to the northwest of Glushko crater.
"We lost a loved one," his voice thickening. "Her name was Carroll — the spouse of Reid, the mother of Katie and Ellie. And we would like to call it Carroll." Forty-five seconds of silence followed. Commander Reid Wiseman wept. The crew embraced. Back on Earth, his daughters were watching from Houston.
That moment matters for reasons beyond sentiment.
Space programs that cannot generate genuine, unscripted human emotion do not survive long.
The reason Apollo endures in cultural memory is not solely the engineering; it is what it said about human reach and courage.
Artemis II, in that moment, made the same claim.
A Moon landing by 2028 remains a stretch. Barber's instinct is that it is more like three to four years away, and that judgement is hard to argue with.
But the smoothness of this mission — from launch to lunar flyby — has shifted the probability in the right direction. The question is no longer whether Orion can fly. The question is whether the landers, the cadence, and the political will can keep pace. The spacecraft, at least, has done its part.
Artemis II a story of inspiration and a story of science. The events had echoes of the Apollo program. At a time when this world has not enough optimism, just as there was so little in the 1960s with wars across the world and civil unrest at home in the US, this was a moment in time when we could for one night remember that we are one. We can see that picture of the Earth.
This is not the end of the story by any means, this is just a test flight for an eventual landing on the Moon — not just one, but many more to come.
https://www.bbc.com/news/articles/cj60nkd8nrko
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NEXT STOP — MARS?
The Artemis program has taken years of work, involved thousands of people and is estimated to have cost $93bn to date.
But for some, there's a distinct feeling of "been there, done that".
More than 50 years ago, America's Apollo missions made history when the first people set foot on the lunar surface. With six landings in total, it felt like the Moon had been well and truly ticked off the space to-do list.
So why is the US spending so much time, effort and money racing to return?
Valuable resources
The terrain might look dry, dusty and seems rather barren, but it's far from that.
"The Moon has got the same elements in it that we have here on Earth," says Prof Sara Russell, a planetary scientist at the Natural History Museum.
"An example is rare earth elements, which are very scarce on Earth, and there might be parts of the Moon where these are concentrated enough to be able to mine them."
There are metals too, like iron and titanium, and also helium, which is used in everything from superconductors to medical equipment.
But the resource that's the biggest draw is the most surprising: water.
"It has water trapped in some of its minerals, and it also has substantial amounts of water at the poles," says Russell.
There are craters that are permanently in shadow, she says, where ice can build up.
Having access to water is vital if you want to live on the Moon. It not only provides drinking water, but can also be split into hydrogen and oxygen to provide air for astronauts to breathe, and even fuel for spacecraft.
RACE FOR SPACE DOMINANCE
America's Apollo missions of the 1960s and 1970s were driven by a race for space dominance with the Soviet Union. This time around China is the competition.
China has been making fast progress with its space program. It's successfully landed robots and rovers on the Moon, and says it will get humans there by 2030.
There's still prestige in being the first to plant your flag in the lunar dust. But now it really matters where you plant it.
Both the US and China want access to the areas with the most abundant resources, which means securing the best lunar real estate.
China put its flag on the Moon when it landed a robotic spacecraft in 2020.
The United Nations 1967 Outer Space Treaty says that no country can own the Moon. But when it comes to what's found on the Moon, it's not quite so straightforward.
"Although you can't own a piece of the land because of the UN treaty, you can basically operate on that land without anybody interfering with it," says Dr Helen Sharman, the first British astronaut.
"So the big thing right now is to try to grab your piece of land. You can't own it, but you can use it. And once you're there, you've got it for as long as you want it."
Paving the way to Mars
Living on Mars will be much harder than the Moon
Nasa has its sights set on Mars and wants to send people there by the 2030s.
Given the technological hurdles it needs to overcome, it's a pretty ambitious timeline. But you have to start somewhere, and the US has decided the Moon is that place.
"Going to the Moon and staying there for a sustained period is much safer, much cheaper and much easier to be a test bed for learning how to live and work on another planet," says Libby Jackson, head of space at the Science Museum.
On a Moon base, Nasa can perfect the tech to provide the air and water astronauts need. They'll have to work out how to generate power and build habitats to protect people from extreme temperatures as well as dangerous space radiation.
"These are all technologies that if you try them for the first time on Mars and they go wrong, it's potentially catastrophic. It's much safer and much easier to try them out on the Moon," Jackson says.
Mysteries yet to be unlocked
Scientists can't wait to get their (gloved) hands on material from the Moon.
The rocks brought home by the Apollo astronauts transformed our understanding of our celestial neighbor.
"They told us that the Moon was formed by this incredibly dramatic event, where a Mars-sized body smashed into the Earth and the bits that came off formed the Moon. We know about that because of the Apollo rocks," says Prof Sara Russell.
But she says there is still much to discover.
Because the Moon was once a part of the Earth, it holds a record of 4.5bn years of our own planet's history. And with no plate tectonics, or wind and rain to wipe this record away, the Moon is a perfect time capsule.
"The Moon is a fantastic archive of the Earth," says Russell. "A new haul of rocks from a different area of the Moon would be amazing."
Inspiring a new generation
It's hoped that the Artemis missions will excite people about careers in science, technology and engineering
The grainy black-and-white footage beamed back from the Apollo missions transformed the dream of space into a reality.
And while only a lucky few watching would become astronauts themselves, many went on to careers in science, technology and engineering.
Black-and-white footage beamed back from the Apollo missions transformed science fiction into reality
It's hoped that the Artemis missions - streamed live and in 4k - will inspire a new generation.
"We live in a world of technology. We need scientists, engineers and mathematicians - and space has a brilliant ability to excite people about those subjects," says Libby Jackson.
New jobs and a thriving space economy will give the US a return on the billions of dollars it's poured into Artemis. As will any spin-offs from the technology developed for the missions that have a use on Earth.
But Helen Sharman says a return to the Moon will also give the world a much-needed boost.
"If we really come together, we can produce so much that's beneficial to humankind," says Sharman.
"It shows us what humans are capable of."
https://www.bbc.com/news/articles/cd6wp6xenv0o
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NEVER AGAIN: ON THE DEATH OF UNIVERSALISM AFTER GAZA
Whether humankind can survive the combined onslaught of climate change, rampant aggressive dementia, and destructive artificial intelligence technologies is currently uncertain.
It is certain, however, that civilization—the progressive “humanization” of the human, the predominance of language over the natural ferocity of instinct—is disintegrating.
We have long perceived the signs of this disintegration; we have long seen that liberal deregulation has been paving the way for the prevalence of force in relationships between human animals.
Now the collapse is underway, after the atrocious aggression unleashed by Hamas on October 7, 2023—an aggression that must be defined as a pogrom, similar to those that the Jewish people have suffered over the centuries in many European countries, and similar to those that the Palestinians of the West Bank have suffered for years at the hands of armed gangs of Israeli settlers.
In the year of uninterrupted atrocity that followed, the failure of the project called “civilization” became evident, and ferocity regained the upper hand: the return of the beast in human history, the return of homicidal violence as a primordial reflex of self-defense and survival.
The name Gaza appears for the first time in the military documents of Pharaoh Thutmose III in the fifteenth century BC.
In Semitic languages, the city’s name means “fierce.” Throughout history, men have often given themselves high-sounding titles, exhibited aggressive postures, and threatened disasters; similarly, the Gazawi called themselves “ferocious.”
The unhappiness of the world depends to some extent on this self-identification with greatness and ferocity, with a power that we do not have but that we like to flaunt and that we are sometimes forced to flaunt in the hope of frightening others who are, in reality, more ferocious than us.
That sandy strip of land overlooking the eastern Mediterranean is mentioned many times in the Bible, and in ancient Egyptian documents and inscriptions of Ramesses II, Thutmose III, and Seti I.
When the Israelites arrived in the Promised Land, Gaza was a Philistine city, and among its inhabitants were the Anakim, a population that was dwelling in the mountainous regions of Canaan and some coastal areas. It was in Gaza that Samson, blinded and in chains, caused the temple dedicated to the worship of Dagon, where over three thousand people could gather, to collapse. He himself died, along with thousands of Philistines.
After October 7, 2023, the Israelis reacted with ferocity.
Ferocity is an animal reflex inscribed in the instinct of self-preservation.
The beginning of the extinction of so-called civilization is marked by this return of ferocity as the sole regulator of exchanges between humans.
At least in recent centuries, civilization has been essentially the attempt to submit ferocity to politics and instinct to will, which can together be summarized as the submission of chaos to language.
After Gaza, it is time to recognize that this attempt to humanize history has failed, and that there will not be a second try.
It is time to recognize that the experiment called “civilization” has failed. What is left of civilization is the destructive power of technology — particularly, military technology. When ferocity prevails, technology becomes a function of war.
We are left now with our ability to kill in a much more sophisticated and systematic way than any other ferocious animal.
“Thinking Gaza” means first of all recognizing the irremediable failure of the universalism of reason and democracy — that is, the dissolution of the very core of civilization.
But it also means looking for escape routes from the future that awaits us, and that awaits those who have been born in this century that promises to be the last.
To those who were conceived in the dark light of this final century, we owe this last act of thought, so that they can desert history, along paths that we cannot yet imagine.
“Thinking Gaza” implies the acknowledgment that words mean the opposite of what they are supposed to mean according to history, psychology, and semiotics.
In the age of ferocity, language is only useful to lie, to cheat, to subjugate, and to exploit.
In current discourse, in hyperaccelerated media, there is no time for critical analysis, there is no time for ethical discrimination. There is no time to listen and to understand.
Techno-media temporality is contracted to such an extreme that understanding and critical elaboration are impossible. This implies that human history is over, because the human (beyond any speciesist privilege) is the sphere where words have meaning, and can be interpreted, so that language can mediate the relations between bodies.
Ever since language became another battlefield where the most powerful imposes his own interpretation, ever since the paths of criticism and independent thought were cut off in the name of speed, we have entered the realm of ferocity.
In the realm of ferocity, every form of language becomes a tool for extermination.The law was intended as universal frame for regulating the relationships between the actors of the social game, who were considered subjects of language.
In recent centuries, the law has established itself as a universal discourse, alternative to the ferocity of tribal belonging.
The modern assertion of the universality of reason was made possible by the Jewish intellectual tradition: by the contributions of those who were allowed to think in a nomadic place, in a place that was not a place of belonging.
Even the internationalist idea, supported by communist workers, has been made thinkable thanks to the contribution of Jewish culture, which was free from ethnic or territorial belonging.
This is why the tragedy of Gaza seems definitive and irremediable: because a state and an army that pretend to be the expression of that culture, as the heirs of that history, have betrayed the Jewish intellectual contribution to modern civilization.
The failure of universal reason and the betrayal of modern Jewish culture are two sides of the same coin. From its start, the State of Israel has betrayed and denied the Jewish intellectual tradition; but today, after Gaza, this disdainful negation of the very illusion of the universality of human reason has become Israel’s political program and common sense.
This is the lesson that Israel has given us: in the sphere of history, the victims do not know how to and cannot ask for peace or reparations but can only seek revenge. This means that today’s victims will never be anything other than victims, unless they manage to transform themselves into exterminators.
The fight against Nazism and the victory against Hitler’s Germany appeared as a reassertion of the principles of modern universalism.
The Nazis’ ferocity was defeated by the symmetrical ferocity of the antifascist powers, but beyond the ferocity of the Second World War, a time of peace, of law, of democracy seemed poised to emerge and to last forever.
This was the meaning of Nie wieder: “Never again.” Those words were at the foundation of the cultural and political education of the generation that grew up after the end of the Second World War—my generation.
Looking back today, I feel that this belief was an illusion.
“Never again” was temporary, because the foundations of a society capable of expelling ferocity from the sphere of human civilization had not been laid.
https://lithub.com/never-again-on-the-death-of-universalism-after-gaza/
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SWEDEN’S BACK TO BOOKS MOVEMENT
Sweden's government is championing a renewed focus on physical books, paper and pens in classrooms, designed to reverse falling literacy levels.
But doubling down on analogue tools has drawn criticism from tech companies, educators and computer scientists, who argue it could impact pupils' employment prospects, and even damage the Nordic nation's economy.
At a high school in Nacka just outside Stockholm, final-year students are unpacking laptops from rucksacks and tote bags, alongside items they say they used less frequently a few years ago.
"I now go home from school with new books and papers often," says Sophie, 18. She says one teacher "has started printing all the texts that we use during the lesson", while a digital learning platform in maths lessons has been swapped out for textbook-only teaching.
It's an image that clashes with Sweden's reputation as one of Europe's most tech savvy societies, thanks to high levels of digital skills, and a thriving tech start-up scene.
Laptops became mainstream in Swedish classrooms in the late 2000s and early 2010s. By 2015, around 80% of pupils at municipal state-funded high schools had individual access to a digital device, according to official data.
The compulsory use of tablets in pre-schools was included in the curriculum in 2019, as part of the previous Social Democrat-led government's mission to prepare even the youngest children for an increasingly digital work and private life.
But the current right-wing coalition, which came to power in 2022, is moving teaching in a different direction.
"We're trying, actually, to get rid of screens as much as possible," says Joar Forsell, an education spokesperson for the Liberal party whose leader is Sweden's education minister.
"With higher ages in school you might use them a little bit more, but with lower ages, or in school, I don't think we should use screens at all."
The government has frequently used the slogan "från skärm till pärm", which sounds catchy in Swedish, and translates to "from screen to binder".
It argues that screen-free lessons create better conditions for children to concentrate and develop their writing and reading skills.
Opinions about the change are mixed among high school children in Nacka
Since 2025, pre-schools are no longer required to use digital tools, and tablets aren't given to children under the age of two.
Later this year a ban on mobiles in schools – even for educational use – comes into force.
Schools have already been allocated more than 2.1bn krona ($200m; £157m) in grants to invest in textbooks and teacher guides. A new curriculum designed to enforce textbook-based learning is due in 2028.
"Reading real books and writing on real paper, and counting with real numbers on real paper, is much better if you want kids to get the knowledge they need," argues Forsell.The shift in approach followed a consultation in 2023 involving academic researchers, teaching organizations, public agencies and municipalities.
"There's been an increased awareness of the disruption that technology is causing in classrooms," says Dr Sissela Nutley, a neuroscientist affiliated with the Karolinska Institute in Stockholm, who is amongst those who have raised concerns about the use of digital tools.
Nutley says that pupils can lose concentration through seeing what other children are doing on screens. She also points to a growing body of international research which suggests reading texts on digital devices can make it harder for children to process information, and that heavy screen use can even impact younger pupil's brain development.
The government hopes the shift back to more traditional teaching methods will help improve Sweden's standing in the Pisa rankings — the Organization for Economic Co-operation and Development's (OECD's) benchmark for core educational subjects. Once a star performer, Sweden's scores plummeted in 2012, and after a brief recovery, saw another significant dip in maths and reading in 2022.
Although still slightly above the average for OECD nations, the country performed worse in literacy in 2022 than countries including the UK, US, Denmark and Finland. Almost a quarter (24%) of students aged 15 or 16 did not reach a basic level of reading comprehension.
"We know that the kids that have been going through the whole school system with a lot of screens – that they're lagging behind in international surveys," says Forsell.
A report into education in Sweden, released by the OECD in January of this year, concluded that, on balance, Swedish pupils benefit from access to digital tools.
However, it highlighted a high prevalence of digital distractions in Swedish classrooms, and found that a heavy use of digital devices in maths lessons correlated with lower results —although scores were, notably, still higher than amongst those who used no digital devices at all.
Andreas Schleicher, director for education at the OECD, urges caution around attributing "cause and effect", yet suggests that Sweden's previous more "extreme" adoption of technology compared to other countries is likely to have impacted its results.
"It just put a lot of devices and technology into classrooms without clear pedagogical intent, without clear goalposts," he argues.
But in Sweden, the government's back-to-books strategy has sparked fierce debates in the business community.
A new report from trade association Swedish Edtech Industry warns that a more analogue education risks pupils being underprepared for future jobs.
"Everybody needs digital basic skills in order to enter the workforce," argues Jannie Jeppesen, the association's CEO and a former teacher. She cites a recent EU report which estimates that 90% of jobs will soon require digital skills.
Jeppesen is also worried about the impact on entrepreneurship and innovation. Sweden is currently Europe's leading factory for tech "unicorns" (companies valued at $1bn [£740m] or more), in relation to the size of its population.
These include music streamer Spotify and Legora, an AI platform for the legal profession.
These types of companies "will move elsewhere" if they can't find the right IT competences in Sweden, argues Jeppeson.
There is also the issue of the growing global use of artificial intelligence (AI). The Swedish government wants secondary schools to start giving lessons on the opportunities and risks of using AI, but some critics say that AI should also be part of the curriculum for younger children too.
Without such measures, younger children from richer families, whose parents are more likely to be able to help them understand how to use AI tools, will gain an advantage creating a "digital divide", warns Prof Linnéa Stenliden, at Linköping University's Department of Behavioral Sciences.
But back at Sweden's parliament, Forsell insists children should not be taught about AI before they've mastered other basic skills, and rejects the idea that the government's more traditional approach to education will broaden inequality.
"You can only give people the opportunities that inequality is taking away from them, by giving them proper education," he says.
However, Jeppesen, the Swedish EdTech industry CEO, argues this is a "populistic" stance. She says the government's focus on digital versus analogue classrooms steers the focus away from other factors potentially impacting results.
This includes the unequal distribution of educational resources and teaching capabilities, highlighted by a March report from Sweden's Education Agency.
In Nacka, the views of final year pupils are also divided.
"The internet has kind of taken over the younger generations, and I've noticed them kind of lose focus easier," says Alexios, 18, who doesn't want his younger siblings to use digital tools in school as much as his generation did.
But others, like 19-year-old Jasmine, are in favor of a digital education, even for primary school aged children. "Let's focus more on computers. Because if we are being realistic, the whole world is using computers."
https://www.bbc.com/news/articles/cly0vk77vdko
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INDUS VALLEY CIVILIZATION
We just acquired insights into why the Indus Valley Civilization collapsed.
It was one of the first urban centers on Earth and contemporary with other cradles of civilization, such as those in Mesopotamia and Egypt. It was located around the border of modern-day India and Pakistan and existed between 3000 BC and 1500 BC.
It reached its height between 2500 BC and 1900 BC, when it constructed sophisticated water management systems and cities with advanced infrastructure, including sanitation with private toilets with water flushing and underground drains.
Examining stalactites in Indian caves and other indirect and direct clues revealed that the fall of the Indus Valley Civilization wasn’t sudden but was associated with century-long droughts; each spell of this climatic disaster caused urban centers to shrink, affecting between 65 and 91% of the arable land. One of these low harvest periods lasted an astounding 113 years, and others lasted about 85 years.
Each time this natural disaster occurred, people had to abandon some of their previously fertile lands and move closer to the Indus River, where water still flowed to feed their population, but it led to a gradual decline in the sophistication of the Indus Valley Civilization.
Besides these climatic changes, some rivers changed course, which led to the previously constructed irrigation systems losing their role, and trade with Mesopotamia collapsed, along with economic decline.
We no longer think the Indus Valley Civilization declined due to invasion, and it didn’t completely disappear. Although people abandoned urban life, they moved further inland into the Ganges Valley and carried many of their cultural practices, which later influenced subsequent societies of the Indian Subcontinent. ~ T. Barczuk, Quora
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RACE, FERTILITY, AND THE SCIENCE OF SLAVERY IN ANTEBELLUM AMERICA
Pseudoscience about mixed-race women’s fertility helped justify slavery in nineteenth-century America.
Cordelia Sanders, a mixed-race woman, daughter to Richard Walpole Cogdell and Sarah Martha Sanders, ca. 1860.
In the 1840s, “the first generation of professional scientists in the new American republic” were obsessed with the fertility of mixed-race women, explains scholar Myrna Perez Sheldon. Called mulattos, mestizos, métis, quadroon, octaroon, or quintroon, these women were considered by members of the American School of Anthropology to be “hybrids” of two distinct races, the “Caucasian” and the “Ethiopian.”
These were two of the five world races defined by the influential German naturalist Johann Blumenbach. According to polygenism, one of the most important constructions of race in the mid-nineteenth century, each of these distinct races had separate origins, either by divine creation or, in later interpretations shaped by Darwinian thought, by distinct evolutionary paths. Either way, white theorists placed white people at the apex of human development.
American School of Anthropology members Samuel George Morton and Josiah Nott, for instance, postulated that mixed-race women were less fertile than either Black or white women, “a claim they asserted was proof of the species distinction between the two races.” Morton was infamous for his skull collection: he measured brain capacity to argue that whites had larger brains. Nott took up Morton’s mantle after the latter’s death in 1851 and was a “full-throated” cheerleader for slavery. Nott also wrote that “probable Extermination” of the white and Black race would result from intermarriage.
Morton, Nott, and company based their beliefs about human hybrids on animal analogies: horses and donkeys could breed, but the resulting offspring, mules, were sterile, which meant that horses and donkeys were separate species in the genus Equus. Even earlier, Edward Long’s The History of Jamaica (1774) had claimed that mulattos were actually sterile—the ultimate proof that whites and Blacks were separate species. (Long’s view was, of course, nonsense.)
Decades before eugenics peaked around the turn of the twentieth century, eugenic thinking lay at the foundation of chattel slavery. Debates over the fertility of mixed-race women were enmeshed in what was essentially a mass slave-breeding program in the US—reproduction as a form of population control.
“The fecundity of mixed-race women was potentially economic profit, but it was also a threat, as it disestablished the color line that was the keystone of slavery’s infrastructure.”
The US ban on the Atlantic slave trade after January 1, 1808 did not lessen the demand for enslaved labor. An illegal African slave trade continued, but the slave states depended for new labor on the domestic control of the reproduction of enslaved women.
Plantation owners in the older eastern seaboard states, sitting on land growing ever less productive, found that the real money was to be made in selling the enslaved “down South,” or “down the river” to newer plantations in the Mississippi Delta. “The reproduction of these women was essential to the future stability of the plantation economy, as well as to the immediate wealth of enslavers.”
As Perez Sheldon documents, the phrase “her generating qualities” was often found in the “for sale” descriptions of the enslaved in the decades just preceding the Civil War. The language of “livestock breeding was used to commodify the reproductive potential of enslaved persons.”
However, for the economy of slave-breeding, “‘breeding true’ to the racial line was an essential but intractable problem.” It was slavery, after all, that produced mixed-race women in the first place, in the “violence born out of colonialism and the Atlantic slave trade.” While the scientists might have looked askance at what was happening, since it violated their notions of the separate races, mixed-race women also literally “produced the slave society of which they were a part.”
“And even after the Civil War, as Darwinian science transformed sexual desire into the engineer of race, the biopolitical imperatives of the American nation-state ensnared the lives and choices of mixed-race women.”
https://daily.jstor.org/race-fertility-and-the-science-of-slavery-in-antebellum-america/?utm_source=firefox-newtab-en-us
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“ALL FLESH IS GRASS”: HOW GRAINS AND GRASSES FED HUMANITY
As I walk through the broomsedge in June, dozens of grasshoppers clatter away with every footstep. Bees and wasps wing past, leafhoppers spring, and beetles scurry for cover. This productivity is why so many birds depend on grasslands for their breeding or wintering. Grasslands, especially those in humid areas with good soil, provision their local food webs as richly as do forests.
Grasses also build soil. Their leaves send about two thirds of all the food they make to the underworld. There, roots tunnel many meters down. As they grow, they break up clay and rock, exude sugars and other molecules, and interweave their cells with fungi. When the roots die, they add spongy organic matter to the soil. This soil‑building process is so productive that it lifts the ground. When a degraded grassland returns to health, the ground heaves up, as if inhaling with relief.
In old grasslands, the soil can be rich with organic matter to a depth of several meters. When prairie goes under the plow, most of the organic matter disappears, turning living water‑holding, nutrient‑rich soil into mineral dust. Today, despite widespread degradation of grasslands, one third of all carbon stored on land is still locked up in grassland soils.
As fellow volunteers, the staff of Birds Georgia and I sow grass seed, we enact the grassland ethos: Build community, one species helping another. Grasses are creators. They use cooperative partnerships to build their homes, places that, in turn, open possibilities for others. They hoard soil carbon, create habitat for other plants, and feed animals.
Although we don’t often imagine ourselves in this way, we are a prime beneficiary, a species built by grass.
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What’s for dinner? Grass. Wherever you live, some kind of grass is probably feeding you.
When the prophet Isaiah proclaimed that “all flesh is grass,” he intended a commentary on the fleeting nature of human life, but he also spoke an ecological truth. In Isaiah’s time and in ours, grass sustains us. If we stacked in 50‑kilogram sacks the total cereal harvest in 2023, the pile would reach to the moon forty times. That’s 2,836 million metric tons of grass flowers matured into seed.
Three grasses—rice, maize, and wheat—account for 90 percent of this superabundance, supplying us with two thirds of food calories. The juices of sugarcane, another grass, supply another 1,900 million metric tons. Barley, sorghum, oats, millet, rye, and wild rice are grasses, too.
Livestock fattens on grass from pasture and the maize‑filled troughs of feedlots. While our great ape cousins feed on forest fruits, leaves, and animal prey, we depend on grasses. If we named ourselves for our primary food, we would be grass apes, Homo poaceae, for Poaceae, the scientific name for the grass family, from the ancient Greek for “fodder.”
It is the nutritive gifts of grasses, with help from oil‑rich fruits like mustards and oil palms, that caused the increase in food calories available to humans over the last millennium and, especially, the last century. The cereal harvest in 2023 was 50 percent higher than that of 2000 and three times that of the 1960s, outpacing human population growth on all continents.
Famines are rarer than they were and now largely emerge from human injustice and war, not the failure of plants to yield food. Such productivity comes with severe costs: felled forest, mined and synthesized fertilizer, among many. But those who in the nineteenth and twentieth centuries made erroneous predictions of imminent mass starvation erred by underestimating the world‑changing potential of grasses.
These global patterns are evident in kitchens. At home, the bottom drawer of our kitchen cabinet grinds when I pull it open. The poor thing has worn sliders and is loaded with bags and tubs. Bread flour, whole wheat flour, all‑purpose white flour, masa, purple cornmeal, medium‑ground yellow cornmeal, plain fine cornmeal, semolina flour, barley flour, and sorghum flour. Some are baking staples, ingredients for pancakes, loaves, and corn breads.
Others are aspirational, plucked in moments of enthusiasm as Katie and I push our cart through the aisles of the Dekalb Farmers Market, a bustling warehouse near our home stocked with bulk dried goods and fresh produce from across the globe. Regardless of their origin, every one of the flours in our kitchen drawer is ground‑up grass seed, the product of a mature grass flower. Other kitchen drawers hold rice and pasta, also made from grass seed. Our kitchen, like kitchens over much of the world, is a bouquet of grass.
From the three hundred thousand species of flowering plants on Earth, we’ve plucked a handful of grasses and founded modern agriculture on their productivity. What made grass so special? The answers reveal not only why we latched onto them so firmly, but also how grasses managed to take over much of the planet long before humans evolved.
Grass flowers are super‑mothers, giving their embryos ample provisions. Under a magnifying glass we can see how. I pull open the complaining kitchen drawer and dip a teaspoon into some bags, retrieving flours that I dust onto scrap paper under a bright counter light. What looked to my unaided eye like powders of different colors reveal themselves under the lens as diverse and beautiful. I expected white flour to look fluffy, but magnified it looks like coral sand. I smooth the tiny pile with the back of my spoon and the flour becomes a miniature tropical beach, a gleaming expanse enlivened with a scattering of darker grains.
Whole wheat flour seems made of tan‑colored sand mixed with shredded cardboard, as if a hurricane had passed through a shipping warehouse on its way to the beach. The grains of purple cornmeal are larger than those of the wheat flours and are intermixed with white‑blue pebbles and chunks of broken obsidian. Uncooked rice grains loom over these sands. They are slightly translucent and etched with lines, as if ancient Egyptians had built their obelisks from milky glass. Who needs magic mushrooms when we have 7× hand lenses?
Most of what I’m admiring under the lens are not the tissues of the seeds’ embryos, but the ground‑up remains of the lunch box that the mother flower carefully packaged and gave to each of her departing children. White, tan, and purple “sand” and the glassy bulk of the rice grain are all what botanists call “endosperm,” a tissue that feeds the embryo when it germinates. Endosperm is only found in flowering plants, although a few close relatives like the nonflowering shrubby joint fir, Ephedra, have its rudiments. The evolution of endosperm was one of the innovations that gave early flowering plants an edge.
Orchids and a few other flowering plants secondarily lost or reduced their endosperm when they evolved tiny seeds. Without endosperm, orchid seedlings are entirely dependent on fungi. Grasses went the opposite way, swelling the endosperm to such an extreme that the embryo looks like an afterthought, a bundle squashed into one end of the seed. Such ample provisions give grass seeds a measure of independence, at least at first. If you’ve ever sprouted wheat grains, you know that grass seeds can lance roots and baby leaves with no help from fungi or other partners. Later in life, community building becomes more important for grasses, but their seeds can go solo.
It takes strange sex and disturbing sibling relations to make endosperm. When pollen grains hatch on the female stigma of a flower, each pollen grain first grows a tube toward the egg, then sends a pair of tailless sperm down the tunnel. If the female part of the plant decides to accept them, both merge with the female tissues. One sperm unites with the egg, making an embryo. The other unites with ladies‑in‑waiting cells nestled alongside the egg.
This second fertilization forms a sibling that never develops root or stem, but instead fattens with starch and other food, all drawn from the mother flower. This is the endosperm. Every seed of a flowering plant carries two genetic individuals. One, the embryo, can grow into a new plant. The other, the endosperm, is an undifferentiated mass of cells whose fate is to feed its sibling and die in the process.
I look on my piles of flour with horror. Not only am I admiring pulverized embryos, most of what I’m seeing are the remains of creatures that, thanks to evolution, grew into starchy blobs destined to be devoured by their siblings. The mushroom trip just took a bad turn. At lunchtime, hunger overrides my qualms. Endosperm makes excellent bread, rice, or tamales. Thank you, doomed siblings.
Among agrarian humans, endosperm left its mark on our genomes. People whose ancestors ate a lot of endosperm have extra copies of the genes that make starch‑digesting enzymes.
Evolution has built dependence on wheat, corn, and rice into some human DNA. Grass lives inside us. It also linked us into new mutually beneficial relationships with other creatures, as flowering plants so often do. Fermentation by bacteria and fungi is central to many grass‑based human foods, including wheat bread, beer, and dozens of fermented rice and corn dishes. Grass, microbes, and humans are a powerful trio of cooperators.
Endosperm reserves made grasses especially good at thriving in challenging conditions. Once tucked inside the seed coat, the starches, oils, and protein in endosperm keep for months. Endosperm is the original dry pantry. Grass seeds can bide their time, waiting for the right conditions to germinate. When rains and warmth arrive, the endosperm digests itself and shunts food to the growing seedling. Powered from within, grass seedlings lance out roots and stems, beating any competition.
It is no accident that many of the most successful recent transcontinental transplants of modern plants are grasses, often causing problems in natural habitats and agricultural fields as they push out local species or desirable crops. Looking further back in time, the fossils and family trees of grasses show that they’ve been colonizing new lands for millions of years, largely thanks to the endosperm in their seeds. These Vikings are successful not because they are warlike, but because their mother flowers sent them out with food hampers.
Like a duckling that emerges from the egg ready to feed itself and scurry away from predators, grasses are ready to take on the world from the moment they “hatch.” Unlike the mostly undifferentiated embryos of their close relatives, grass embryos have roots, miniature stems and leaves, and a placenta‑like structure connecting to the endosperm. Once conditions are right, the embryos are ready to burst into action. A rice grain or wheat kernel in your hand might look passive, but you’re holding a time capsule with a sprinter coiled inside.
What I’ve called “seed” or “grain” is technically the fruit of the grass flower. Like all other flowering plants, grasses wrap the embryo and endosperm in layers of maternal tissue. Unlike fleshy fruits like plums or mangoes, the fruit tissues of grasses are thin and papery. In whole wheat flour, these fibrous coverings are called the “bran,” the cardboard‑like material that I saw under my lens. The “wheat germ” is the embryo, little flecks of chewy brown. White flour is nearly pure endosperm. Like drinking cow’s milk, when we eat white bread or pasta we’re getting a slug of energy and nutrients built by evolution for the rapid growth of infants. Perhaps pasta or pizza with cheese is so comforting because we’re literally being mothered by flowering plants and bovines?
Not content with a tightly bundled fruit, grasses add extra papery layers around the seed, like gift wrap gone mad. A swarm of botanical terms describe the details of these wrappers—floret, glume, lemma, awn, palea, lodicule—but we usually refer to them as mere chaff, the fibrous junk that stands in the way of our hunger for endosperm. This name belies the intricacy of each species’ arrangement of parts. Some look like nested canoes, others like sheathed javelins. Many are arranged in geometric patterns of fans or rows.
Each arrangement serves to launch the young on a journey suited to the ecology of its species. Many have wind‑catching bristles. Some are grappling hooks for mammal fur or bird wings. I once made the mistake of wearing wool socks to walk through grassland at Panola Mountain and later spent hours unpicking hundreds of sharp, grippy grass seeds, a reminder of how well they cling to fur. Other grass seeds twist as humidity changes, drilling seeds into the soil. The collective term for all these fruit wrappers built by the mother flower is “spikelet,” a feature that evolved in the ancestor of modern grasses that has literally carried them, by wind and animal bodies, to worldwide success.
These winning characteristics of grass seeds were lately helped by a few quirks that made them especially alluring to humans. We have delicate guts, unable to tolerate the poisons and tannins that lace the seeds of many other flowering plants. For example, a few seeds of larkspur would kill you by alkaloid poisoning. Without repeated soaking in water, acorns sicken us with bitter tannins. Our saliva has only weak levels of the tannin‑neutralizing chemicals that other mammals use to tolerate bitter food.
Compared with the seeds of almost every other plant, grass seed is highly palatable, especially for a dexterous ape whose hands can slough off the chaff. Many grasses evolved to be partly dispersed by herbivorous mammals, the seeds passing through guts with the bulky leafy tissue.
For millions of years, then, it has been in the interest of grasses not to have poisonous seeds, although many have tough or bitter coats to deter fungi, insects, or overenthusiastic grazers. When our ancestors started to gather and replant seeds, grasses were the obvious choice: edible, portable, rot resistant, and stuffed with easy‑to‑digest food.
When grass fruits mature, they usually detach from the parent, hitching a ride on an animal or the wind. Botanists call this process “shattering,” because a single touch of a ripe seed stalk can cause all the fruits to snap and tumble, like shards of broken glass. The mother plant encourages this fracture by killing and partly digesting the cells where the mature fruits attach to her stalk.
In some grass species shattering can be turned off by just one or two gene mutations. The mother fails to cut the umbilicus and the fruits cling tight. In the wild, these mutants are hopeless, failing to send offspring into the world.
But when clever bipeds evolved, our ancestors, the doomed mutants became, literally, the seeds of the agricultural revolution. By not falling to the ground, the shatterless mutants stayed on the stalk until we were ready to harvest them. By selectively keeping and replanting the mutants, ancient humans gained the first cereal crops.
Today, when we bite into a wheat sandwich, a corn tamale, or a rice curry, we’re eating descendants of these shatterless mutants.
Other mutations, random genetic changes that humans noticed and kept for planting the next year, helped along the way, notably those that multiplied the number of fruits on the stalk and fattened each seed. Many cereal crops also went through repeated rounds of genome duplication and hybridization, just as goatsbeard did. But without early shatterless mutations, our species would never have enmeshed its fate so deeply with grasses.
Imagine a world where rice, wheat, or corn remained minor, “wild” foods. Agriculture would be vastly less productive. Human population size would be a fraction of what it is today. Few genetic changes have been as consequential for the story of life on Earth. The shatterless mutations launched humans on our present trajectory. We’ve been clearing forest and tilling fields for grasses ever since.
The book of Genesis, the origin story of a grass‑based agrarian culture, tells us, “In the sweat of thy face shalt thou eat bread.” God decrees: Humans toil on behalf of grass. But our dependence on grass far predates the origins of agriculture or written scriptures. Without grasses, we’d still be small‑brained apes living in the trees.
https://lithub.com/the-origin-of-our-species-how-grains-and-grasses-fed-and-still-feed-humankind/
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ICE AGE VERSUS A GLACIAL PERIOD
For most of Earth's 4.5 billion-year history, the poles were completely ice-free. Today, they are frozen solid—because we are actually living in the middle of an ice age right now.
While there are multiple misconceptions about Earth's climate history, the most widespread is confusing an "ice age" with a "glacial period."
In geological terms, an ice age is defined simply as a period when the Earth has permanent, year-round ice sheets at its poles. Because Antarctica and Greenland are currently capped with massive ice sheets, Earth is still technically in the Quaternary Ice Age, an epoch that began roughly 2.58 million years ago.
What people usually refer to as "the Ice Age" was actually just the most recent glacial period. Ice ages are not uniformly freezing; they fluctuate between two alternating phases:
Glacial periods: Colder phases where glaciers advance across continents. The last one peaked about 20,000 years ago, burying parts of North America and Europe under miles of ice.
Interglacial periods: Warmer phases where the ice retreats back to the poles. Earth is currently in an interglacial period called the Holocene, which began around 11,700 years ago.
Even when the North American ice sheet reached as far south as modern-day New York City, the equator remained relatively warm. Tropical rainforests and savannas continued to thrive, and the global average temperature was only about 6 degrees Celsius (11 degrees Fahrenheit) cooler than the pre-industrial average.
Ice ages are not brief, cataclysmic deep-freezes. They are multi-million-year epochs characterized by the rhythmic advance and retreat of polar ice, driven largely by slight, predictable changes in Earth's orbit and axial tilt over tens of thousands of years.
Understanding this terminology completely shifts how a person views planetary history, revealing that human civilization has flourished not after an ice age, but during a brief, warm pause within one. ~ NovaPrism, Quora
Nin Jahaus:
Humans, through their burning of fossils, could possibly postpone the refreezing by a few thousand years at most. The mechanism and causes of the Pleistocene glaciations (which we are de facto still in) remain an unsolved mystery for current science (March 2026).
This is despite Milankovic's discoveries about the connection between solar activity, albedo, and precession related to the polar ice cap. Current simulations, based on a certain erroneous assumption, cannot answer either the causes of the increasing amplitude of glaciations and interglacials or the direct triggers for both glaciations and such violent interglacials.
Fortunately, this won't last forever. Sooner or later, among the several billion dim-witted people, someone emerges who is ahead of their time and solves a mystery. Often, it's someone we would never expect. Like Darwin or Einstein.
Brian:
Global Warming = we are coming out of an Ice Age, by all accounts…and earth would be doing this anyway. We are accelerating that for sure…and the prospects are uncomfortable.
Global Conservation = climate-wise, those who are paying the closest attention would like to “freeze” this right where it is. To “conserve” what humanity has known. So that we can remain comfortable.
The Earth doesn’t care what we want, or what we do.
Yes, humanity is speeding up warming — the same way the first trees sped up warming. That doesn’t mean that mammoths wouldn’t have still existed while The Pyramids at Giza were being built — arguably 5000 years ago. Before humanity started coughing carbon into heaven.
It’s all very complicated — and cyclical. And while I personally applaud The Conservationists for trying to freeze the clock in order to preserve comfort (and real estate values), I also understand those who believe there is no such thing as Global Warming (they are WRONG to insist it isn’t happening, but also wrong to think uncomfortably isn’t encroaching).
They’re both right AND wrong.
Trying to explain any of it to either faction is a fool’s errand. Better to just know the truth, live life, raise a glass, and get down with The Missus (when she lets you). And buy a house a few miles off the beach if you want your great grandkids to have it. And you can either have one of those heat-sink cooling things built into the house as air conditioning — or not. The great grandkids will have to go outside multiple times. They will adapt or die.
Just like any other organism earth has given birth to.
Chris Malek:
Humans since the Industrial Revolution have caused global warming beyond what would have otherwise occurred. But you’re right: in the end the Earth’s natural cycles will almost certainly overwhelm any human-driven efforts to maintain climate stability.
Humans will adapt and survive. Our largest cities that grew based on their proximity to oceans, for the ease of commerce and travel, may not. The disruption will be massive if/when the polar ice shelves melt.
There are ancient cities from 1000+ years ago under 500 feet of water right now — right next to the harbors they were built on. Adaptation is what we do best.
Humans will adapt and survive, but it will be hugely disruptive with massive costs.
Chris Malek:
I assume the ancient cities you’re referring to are in the Mediterranean region? That’s the only place I can think of with that sort of sea level rise since civilization began.
Brian:
And the Caribbean — and South America. And Asia. And probably Africa — but nobody cares to look there. The world wasn’t strictly “Mediterranean” — to be clear. If you are interested you can Google it. As mentioned, you won’t find much about ancient coastal civilizations in most of Africa, but you will find them underwater from Egypt straight through The Red Sea.
Linas Vytautas Slotkus:
Anthropogenic climate change is real and it IS bad. Whether it's stronger than the cycles that could bring another glaciation period and end the current ice age completely (melt the poles completely) or not may not be clear yet, but human influence on global climate is undeniable.
David M. Browne:
There is no known model that describes the huge increase in CO2 as not causing major change. Is that scary? Yes, when you realize that trillions of investment and billions of people are dependent on existing climate patterns.
Currently, climate change is bring driven almost exclusively by CO2. Humans have increased it greatly in a very short time. Other factors that affect climate move at a far slower pace, so are not much of an influence on current changes.
David Layton:
We are very likely at the end of an ice age — global warming will irreversibly warm the earth up to bring it out of an ice ice melting all the ice. Unless of we manage to restore the atmosphere to an ice level of climate sensitive gases. The effects of axial tilt etc are much weaker than the atmospheric changes currently in progress. Though a nuclear winter might be enough put the earth back again.
David M Browne:
It is uncertain whether there can be another glacial advance with the human increase in C02. There is no data suggesting that its possible. The last similar era with that much CO2, the Pliocene, did not have glacial advance.
Darren Tomlyn:
This is also why it doesn’t take much warming to put humanity into completely unknown territory when it comes to the global temperatures and climate we’ve lived in so far — because it’s all part of such an ‘ice-age’ with glacial periods within. We know that the Earth has been much warmer in the past, which is why the planet will be fine, but humanity — maybe not.
Which is why any human created warming inherently becomes a self-created problem we then need to solve for ourselves.
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WHAT YOU NEED TO KNOW BEFORE TAKING WEIGHT-LOSS DRUGS
Weight-loss drugs are not the quick fix solution that many people believe, especially if you hope to keep the pounds off in the long-term.
Sarah Le Brocq has direct experience of the transformative effects of weight-loss drugs. She has lived with obesity for most of her adult life and tried numerous diets. "Anything that came out, I thought, 'I'll try that because that might work for me'." Unfortunately, the weight always came back, she told the BBC's Inside Health.
After taking weight-loss drugs for more than two years, she has lost almost eight stone (51kg/112lb). "All of a sudden I wasn't thinking about food anymore," she says. "I've just got more energy, I'm doing things I couldn't do before… it's kind of given me a new freedom in life again."
Millions of people like Sarah are now accessing medications like semaglutide and tirzepatide, better known by their popular brand names Ozempic and Mounjaro. The numbers of people on weight-loss medication is only likely to increase as new drugs appear on the market too, including pills rather than the current jabs.
It's clear that these drugs are opening up a new era in the treatment of obesity. The condition, is now a "mitigatable" issue, David Cummings, professor of medicine at the University of Washington tells me. "They are the closest thing I've seen to miracle drugs".
Other academics, however, warn that we risk losing sight of the need for behavioral change, especially as weight tends to be regained quickly when people stop taking the drugs.
So what should anyone planning to use weight-loss medication consider before they start?
How they work
Weight-loss drugs work by suppressing an individual's appetite by mimicking hormones that tell our body when it is full. The most common are known as glucagon-like peptide 1, or GLP-1, and glucose-dependent insulinotropic polypeptide, or GIP.
The drugs bind to specialized molecules on the surface of our cells known as GLP-1 and GIP receptors, which play a key role in telling our body when it has had enough food.
Typically someone taking these drugs will begin to lose weight within the first few weeks. Although the drugs are only approved for weight loss in people with obesity, there is a rapidly growing private market for those not considered clinically obese.
Their popularity has been rising because they are extremely effective, with weight loss of between 14-20% in 72 weeks. But about 10-15% of people lose very little weight, so called "non-responders".
GLP-1s are like "a chemical shield" that protects individuals against our "modern obesogenic environment, filled with cheap, calorie-dense foods", says Naveed Sattar, a professor of cardiometabolic medicine at the University of Glasgow and leads the UK Government's Obesity Healthcare Goals program. He has also consulted on medical trials with several companies who produce weight-loss drugs but does not own any shares.
"There's food everywhere," he says – and within half an hour anyone "can pick up the phone and order 10,000 calories of food".
If you stop, you'll gain weight
If someone living with obesity starts to take weight-loss drugs, they need to consider that they may be on the drug long-term, says Cummings, who runs a weight management program for individuals with obesity who have BMIs of 50 and above.
A common question he is asked by his patients before they start taking a weight-loss drug is how long they will be on it. Typically, they stop taking the drugs after about a year, he says. One analysis of scientific studies involving more than 9,000 patients indicated the average treatment duration was 39 weeks. People believe they can continue to lose weight using their willpower, he says, but the evidence suggests that is not the case.
People stop for various reasons, either due to the expense of treatment, their insurers stopping coverage or individuals not wishing to be on drugs for a prolonged period of time, Cummings has found.
And when people do stop the drugs, their weight tends to rebound. A recent study found that weight regain happens up to four times more quickly after stopping weight-loss drugs compared to someone ending a weight-loss program that focuses on changing their behavior.
Another study found that those on weight-loss drugs gained 1.5kg (3.3lbs) eight weeks after they stopped the medication, with their weight continuing to climb with the more time that passed. The same study also found that other health concerns, such as high blood pressure, also returns. New research has also found that people who stop taking weight-loss drugs gain back around 60% of the weight they lost a year later.
It returns quickly because of something researchers call "food noise", which consists of persistent and intrusive thought around food, says Sattar.
Hormones play a role too. When an individual tries to lose weight, it triggers a powerful hormonal response that tells your body to regain the weight you lost. Cummings explains that because of this, the brain interprets a calorie drop as an energy deficiency, so after stopping weight-loss drugs, hormones that stimulate appetite increase while the rate at which you burn energy – the metabolic rate – decreases. "If these biological defences are strong enough, they can blunt the drug's effectiveness," he says.
Lifestyle change
Sattar has observed that for a small proportion of people who make lifestyle changes, it may be possible to reduce the dose or use the drug intermittently instead. Some really do make "fundamental changes in their diet", he says.
"Others might need it at a lower dose than they would when they started. But the majority will probably still need some dose of the drug because the [food] environment is still the same."
There's also increasing concern that individuals are taking weight-loss medication as a substitute for making life-style changes – even though evidence shows that modifying lifestyle in combination with weight-loss drugs is what will lead to greater weight loss.
Experts have recently cautioned in a scientific review of the evidence that when there's a lack of behavioral and lifestyle support for those on weight-loss drugs, it can leave individuals vulnerable to nutritional deficiencies.
"We need to make sure people are getting enough protein and are getting all the vitamins and minerals they need," says Marie Spreckley a nutrition and behavioral scientist at Cambridge University and lead author of the report. "You don't want to have longer-term unintended consequences, like frailty and muscle loss. We don't want to replace one health concern with another."
Because these medications cause a dramatic appetite reduction, patients tend to eat less overall, she and her colleagues note. This can lead to a "missed opportunity" if patients are not supported long-term and their food choices remain poor.
No quick fix
The World Health Organization has therefore stated that medication alone won't "reverse the obesity challenge". Early interventions, screening and creating healthier environments are also needed, the organization has stated in its guidelines on using GLP-1 drugs.
This is easier when people are still taking the drugs, Sattar says. "You have more mental space to think about your diet."
But behavioral change is extremely challenging, says Amanda Daley, a professor of behavioral medicine at Loughborough University in the UK. She says there needs to be better communication with patients about how quickly they can regain weight once they stop taking GLP-1 medication.
Obesity is a chronic, relapsing condition, she says, which means it cannot be "cured" with a drug alone. That's why additional support and "wraparound care" is key to ensure patients make dietary changes as well as increasing their physical activity.
It's unclear whether private providers are providing this crucial additional support, she says, which she finds concerning since so many people access the drugs privately and it is hard to monitor continuation of care.
Micro-nudges help change behavior
To overcome some of this – researchers at Stanford have looked at how they can help support and encourage lifestyle changes. In one recent study, researchers tested whether small nudges – or "microsteps" – could help encourage healthy behavioural change for those taking GLP-1 medications.
The tiny changes focused on nutrition, physical activity, sleep and stress management.
Crucially, the microsteps were small and manageable, such as swapping sugary drinks for water, no longer drinking coffee after lunch, taking a deep breath when stressed or popping outside for five minutes.
They found these helped improve behavioral expectations. It's this "expectation" that's a first necessary step for behavioral change, says Maya Adam, a clinical associate professor of pediatrics at Stanford School of Medicine, who was involved in the study.
"Achieving your best health involves a lot more than pharmacotherapy alone," she says. "We found that giving people these little nudges may be very effective." She calls these steps "too small to fail" because even small daily changes and habits make a real difference over time.
Side effects
These kind of interventions are crucial to help give people the tools they need to enact change, Daley says, especially considering the known side effects. These include gastrointestinal issues. There has also been an observed increase in pancreatitis and gallstones. Muscle loss is another concern, especially among individuals who are not exercising. Recently a study found links to bone and joint conditions too.
While we now have several years of data on the effectiveness of GLP-1 drugs, we don't yet know what the long-term outlook will be or whether the results will wear off over time. There is also a lack of data on how these drugs affect pregnancy outcomes or future generations, as the advice is not to take weight-loss drugs during pregnancy.
But given the negative health outcomes for those living with obesity, the side effects pale in comparison, both Sattar and Cummings say. This is particularly the case for individuals with multiple weight-related conditions. Heart disease, cancer and stroke are the leading causes of death worldwide – and all are linked to obesity.
A changing landscape
What is clear is that the landscape for weight-loss medication is rapidly evolving.
There are other health benefits too beyond weight loss. In one major study involving two million people, the drugs were linked to better heart health, fewer infections, lower risk of drug abuse and lower incidences of dementia. It's also been shown to improve sleep apnoea, arthritis and substance abuse.
A new drug called retatrutide has also shown promise in recent trials. It mimics three hunger-regulating hormones, and early evidence indicates weight loss of nearly 29%, after 68 weeks according to manufacturer Eli Lilly.
The drugs are but one tool for obesity care, Daley says. More important is the need to make it easier for people to make healthier changes that last beyond medication. And because of the abundance of people eating calorie-dense ultra-processed foods, obesity will continue to be a growing health concern, experts warn.
Our ultimate goal, Daley adds, should be to change the food environment to offer better choices and influence government policy so that the next generation won't need these drugs at all.
https://www.bbc.com/future/article/20260401-why-weight-loss-drugs-arent-a-quick-fix
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WHO BENEFITS MOST FROM WEIGHT-LOSS DRUGS
People who carry variations in two genes linked to appetite and digestion can lose more weight when taking drugs such as Wegovy and Mounjaro to treat obesity, research suggests.
The findings, outlined in the Nature journal, could explain why some people lose far more weight than others and why some have particularly bad side-effects, such as nausea and vomiting, while taking them.
The popular medicines remove feelings of hunger by acting like a natural gut hormone that makes users feel full.
While genes may play a relatively modest role in influencing how well these drugs work, experts say other factors such as your sex, age and even where you come from can also have an impact.
It is thought at least 1.6 million people in the UK have tried weight-loss drugs in the past year, and that number is expected to rise.
Most are being bought privately through online pharmacies. The NHS only offers Wegovy and Mounjaro to a small percentage of people who have obesity and other related health issues.
The percentage of body weight lost when taking weight-loss medication can vary widely. Drug trials suggest 14% weight loss on semaglutide (Ozempic and Wegovy) and 20% on tirzepatide (Mounjaro).
In this study, based on the experiences of 15,000 people taking weight-loss medications, they lost an average of 11.7% of their body weight during roughly eight months of treatment. Some lost 30% of their weight, while others lost little or nothing.
All of those 15,000 had previously signed up for gene-testing by the company 23andMe, which used that data to chart the experiences of people taking weight-loss drugs. By analyzing millions of their genetic variants, the researchers found a pattern suggesting a link between some variants and the effectiveness of the drugs.
Professor Ruth Loos, from the University of Copenhagan, who wrote about the research in Nature journal, said: "The study found a genetic variant associated with weight loss, which was also associated with nausea.
"People lose more weight if they have this variant."
And that extra lost weight amounted to about 0.76kg (1.6 lbs) on average - but those people who carry two copies of the genes can double the amount they lose.
The variant is high in people with European ancestry — 64% carry one copy, while 16% of people carry two copies, she says.
That compares to 7% of African Americans who carry a copy of the gene.
"If you carry the variant, you will lose more weight," says Prof Loos.
The study found another variant that could be responsible for people experiencing side-effects such as nausea and vomiting when taking tirzepatide (Mounjaro).
And that could mean up to 1% of people taking the drug will have really bad vomiting — nearly 15 times worse than normal.'
Prof Loos said the genetic effect, while modest, "is similar to other factors — and not trivial".
However she said the findings need to be reproduced in other studies and, to date, that has not happened.
For Dr Marie Spreckley, from the University of Cambridge, "genetics is only one part of a much more complex picture".
She said the main drivers of outcomes are "behavioural, clinical, and treatment-related factors". So how much daily exercise and healthy eating people do alongside taking the medication, as well as support and advice offered, plus other underlying health issues.
But there are other factors at play too.
Women are more than twice as likely to lose 15% of their body weight on Mounjaro than men, previous research suggests.
Being younger, white or Asian are also thought to be linked to more weight loss —although the reasons are not fully understood.
And the type of medication used, the dose and how long it is taken for have all been linked with greater weight loss.
In the long term, taking genetic and other information together could help guide the choice of which weight-loss drug to use, based on the potential benefits — something called "precision medicine".
But we are not there yet, said Professor Naveed Sattar, metabolic health expert from the University of Glasgow.
"Overall, these findings are scientifically interesting, but they are a long way from changing clinical practice," he said.
"What we really need now is more robust trial data to better define the balance of benefits and harms with these and many other emerging newer therapies."
https://www.bbc.com/news/articles/cn5317dkqnxo?at_objective=awareness&at_ptr_type=email&at_email_send_date=20260415&at_send_id=4582710&at_link_title=https%3a%2f%2fwww.bbc.com%2fnews%2farticles%2fcn5317dkqnxo&at_bbc_team=crm&at_audience_id=266492954
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HOW NEANDERTHAL GENES AFFECT OUR (HOMO SAPIENS) HEALTH
Around 2% of the genomes of modern Eurasians contains Neanderthal DNA. Here's how it affects our health.
The first encounter
By 75,000 years ago, but possibly up to 250,000 years ago, the ancestors of most modern Eurasians first ventured out of Africa and into Eurasia. Here, modern humans came face-to-face with Neanderthals, who last shared a common ancestor with modern humans hundreds of thousands of years earlier and had been living in these continents ever since. On multiple occasions over the millennia, the groups interbred.
At first, modern humans inherited whole chromosomes from Neanderthals, Sriram Sankararaman, a professor of computer science, human genetics and computational medicine at UCLA, told Live Science. However, from generation to generation, via a process known as genetic recombination, these stretches of DNA were broken up and shuffled around.
Neanderthal DNA was generally "deleterious" to modern humans, meaning it was rapidly weeded out of modern humans' DNA through evolution. This resulted in "deserts of Neanderthal DNA," or large regions of the modern human genome lacking it, Sankararaman said. For instance, scientists think the Y chromosome in males doesn't contain any Neanderthal genes. It may be that genes on the Neanderthal Y were incompatible with other human genes or they may have been randomly lost via a process known as genetic drift.
In people who inherited Neanderthal DNA, the X-chromosome also contains a lot less Neanderthal ancestry than other, non-sex chromosomes carry. This is probably because any harmful or nonfunctional mutations on the X chromosome will be expressed in males, because they lack a matching, functional copy of the gene to compensate. That likely created strong evolutionary pressure to remove such harmful Neanderthal genes from the modern human X, Emilia Huerta-Sanchez, an associate professor of ecology, evolution, and organismal biology at Brown University, told Live Science.
But some Neanderthal DNA helped modern humans survive and reproduce, and thus it has lingered in our genomes. Nowadays, Neanderthal DNA occupies, on average, 2% of the genomes of people outside Africa. However, the frequency of Neanderthal DNA that codes for beneficial traits may be as high as 80% in some regions of the genome, Akey said.
Our physical appearance
For many people, the legacy of Neanderthals is apparent in a highly visible feature: skin color.
A Neanderthal gene variant on chromosome 9 that influences skin color is carried by 70% of Europeans today. Another Neanderthal gene variant, found in most East Asians, regulates keratinocytes, which protect the skin against ultraviolet radiation via a dark pigment called melanin.
Neanderthal gene variants are also associated with a greater risk of sunburn in modern humans. Likewise, around 66% of Europeans carry a Neanderthal allele linked to a heightened risk of childhood sunburn and poor tanning ability.
Neanderthals had spent millennia at higher latitudes with less direct sun exposure, which is needed for vitamin D production. Therefore, changes to hair and skin biology may have allowed modern humans to quickly capitalize on lower levels of sunlight while still producing enough vitamin D to be healthy, John Capra, an evolutionary geneticist at Vanderbilt University, told Live Science.
"One of the cool things about interbreeding is that instead of waiting for new beneficial mutations to arise, which is a really slow process, you introduce a ton of genetic variation at once," essentially fast-tracking evolution, Huerta-Sanchez said.
In addition, our ancestors had to adapt to colder Eurasian weather. To do so, they may have acquired Neanderthal genes that affected face shape. In a 2023 study, scientists discovered that modern humans inherited tall-nose genes from Neanderthals. A taller nose may have allowed more cold air to be heated to body temperature in the nose before reaching the lungs, suggested Kaustubh Adhikari, co-senior study author and a statistical geneticist at University College London.
The clock that makes our cells tick
Neanderthal DNA also may have helped H. sapiens adjust to the bigger differences in day and night length at northern latitudes.
Lingering Neanderthal genes affect our circadian clock, which regulates internal processes such as body temperature and metabolism. For instance, some early risers can thank Neanderthals for their circadian clock genes, Capra and colleagues found.
This may have helped our ancestors adapt to shorter winter days farther from the equator, Capra said.
"It seems like it's not that being a morning person is what matters," Capra said. "It's that that's a signal of how essentially flexible your clock is and how able it is to adapt to the variation in light-dark cycles with seasons," he said.
OUR INTERNAL DEFENSES
Many of the strongly retained Neanderthal genes are tied to immune function.
By the time H. sapiens arrived in Europe, Neanderthals had already spent hundreds of thousands of years fighting infections specific to Eurasia. By mating with Neanderthals, modern humans got an instant infusion of those infection-fighting genes.
"Those pieces of Neanderthal DNA, especially the immune ones, that were already adapted against pathogens that Neanderthals had been living with for a long time started to rise in frequency under natural selection in modern human populations," David Enard, an assistant professor of ecology and evolutionary biology at the University of Arizona, told Live Science.
While many of the ancestral pathogens that sickened ancient humans are lost to time, some of the Neanderthal genes that helped fight them off still work against modern pathogens. For example, a 2018 study by Enard and a colleague revealed that modern humans inherited Neanderthal DNA that helped them combat RNA viruses, a group that today includes the flu (influenza), HIV and hepatitis C.
The darker side of Neanderthal DNA
Some of the Neanderthal genes that once helped our ancestors may be harmful in the modern world.
For the most part, Neanderthal genes are not strongly expressed in the brain, which hints that they were strongly selected against during evolution. Neanderthal genes have been linked to mood disorders such as depression and to brain signaling pathways that make people more likely to become addicted to nicotine.
And even the immune boost from Neanderthals may have a downside. In 2016, scientists discovered that Neanderthal genes that prime the immune system to fight pathogens may also predispose people to allergic diseases. In addition, Neanderthal genes have been tied to a higher risk of developing autoimmune diseases, such as Graves' disease, caused by an overactive thyroid; and rheumatoid arthritis, which inflames the joints and even "Viking disease," in which one or more fingers become bent or frozen.
One Neanderthal gene variant may have made us more likely to have a severe case of COVID-19. That variant, found on chromosome 3, is found in half of South Asians and one-sixth of Europeans. But even there, the picture is complicated, as other Neanderthal genes, carried by up to half of people in Eurasia and the Americas, are associated with a reduced risk of severe COVID-19.
"Unfortunately, there are no diseases we can really say, or even traits in general, we can say, 'Oh, you can blame your Neanderthal DNA for that,'" Capra said.
That's especially true for some of the biggest health ailments, such as heart disease and cancer, where dozens or hundreds of genes, along with myriad environmental factors, affect your risk of disease
WHAT LIES AHEAD
So how long will the traces of these long-lost humans linger in our genomes? Over hundreds of thousands of years, some of these Neanderthal fragments will gradually be eliminated from our genomes. Others will become firmly embedded, Akey said.
In the meantime, there's still much more to learn about how Neanderthals left their mark on us.
"Being able to leverage new genomic technology like CRISPR and gene editing is going to play an important role in understanding the actual underlying biology of how Neanderthal sequences contribute to human traits and diseases," Akey said.
Deciphering what these genes actually do could aid the development of treatments for certain conditions, he said.
And the gene flow wasn't one-way; scientists are also trying to determine how modern-human DNA may have influenced Neanderthals and are applying artificial intelligence (AI) methods to ancient genomes to create a more detailed picture of what our long-lost cousins were like.
Figuring out the role of Neanderthal DNA in our genomes does more than help us understand our health. These bits of DNA can provide clues as to what makes us unique, Sankararaman said.
"Neanderthal DNA entered our genomes at an important time in our history," Sankararaman said, when our ancestors were moving into new environments.
"By looking at the fate of these bits of DNA," he said, "we can hope to understand what were the functionally important regions in our genome over this period of time."
https://www.livescience.com/health/genetics/more-neanderthal-than-human-how-dna-from-our-long-lost-ancestors-affects-our-health-today
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MORE ON HOW NEAENDERTHAL GENES AFFECT OUT HEALTH
In 2016, scientists discovered Neanderthal genes in some modern humans that encode proteins that stimulate the immune systems' response to pathogens, and that these genes may also predispose people to allergic diseases.
Modern humans inherited gene variants from Neanderthals in a family of proteins called Toll-like receptors (TLR). TLRs are found on the surface of cells and play an important role in innate immunity — the body's first line of defense against pathogens. TLRs bind to invading microbes and stimulate the immune system to respond.
People who have Neanderthal versions of these TLR genes may be more likely to have allergic diseases, scientists found. This could be because these receptors are hypervigilant and more likely to overreact to environmental allergens.
Pain Sensitivity
People who carry any of three Neanderthal variants in a gene called SCN9A may have a lower pain threshold than those who don't, scientists say.
Neanderthal DNA may also make some people more sensitive to pain inflicted by sharp objects piercing the skin. A 2023 study in the journal Communications Biology found that people in Latin America who carried any of three variants in a gene called SCN9A, which is involved in pain signaling, were more sensitive to pain after being prodded with a sharp object. These variants were more commonly found in people with prevalent Native American ancestry.
"It makes much more sense that a crucial thing like pain, if it gives us a demonstrable change [in our survival chances], would be evolutionarily selected," Kaustubh Adhikari, co-senior study author and a statistical geneticist at University College London, previously told Live Science.
The findings only addressed normal sensitivity to pain, rather than chronic pain, which is when pain lasts for more than three months.
Type 2 Diabetes Risk
Mexicans and other Latin Americans may be at a higher risk of developing type 2 diabetes (T2D) thanks in part to a Neanderthal mutation in a gene called SLC16A11.
SLC16A11 is involved in fatty acid metabolism. Fatty acids likely play a major role in the development of T2D, a disease characterized by high levels of glucose, or sugar, in the blood. T2D is the most common form of diabetes and is known to disproportionately affect Hispanic and Latino people.
Sensitivity to sunlight and hair loss
A heightened sensitivity to burning in the sun and balding could be influenced by gene variants inherited from Neanderthals, research suggests.
Some Neanderthal gene variants are also associated with a greater risk of balding and sunburn in modern humans, according to a 2021 study published in the journal Nature Communications.
Scientists looked at a large repository of health and genetic data from adults in the U.K. and found that, of the 17 Neanderthal gene variants associated with balding, 15 were tied to hair loss rather than hair growth, study co-author John Capra, an evolutionary geneticist at Vanderbilt University, told Live Science.
The researchers also found that Neanderthal DNA was likely to make carriers more sensitive to sunlight. This suggests that these traits may have been beneficial to modern humans entering Eurasia, as those genes may have helped modern humans make the most out of the more limited sunlight available at higher latitudes in Eurasia, Capra said.
A separate study in 2017 similarly found that around 66% of Europeans carry a Neanderthal allele linked to a heightened risk of childhood sunburn and poor tanning ability.
Severe Covid Risk
Some Neanderthal gene variants are also associated with a greater risk of balding and sunburn in modern humans, according to a 2021 study published in the journal Nature Communications.
Scientists looked at a large repository of health and genetic data from adults in the U.K. and found that, of the 17 Neanderthal gene variants associated with balding, 15 were tied to hair loss rather than hair growth, study co-author John Capra, an evolutionary geneticist at Vanderbilt University, told Live Science.
The researchers also found that Neanderthal DNA was likely to make carriers more sensitive to sunlight. This suggests that these traits may have been beneficial to modern humans entering Eurasia, as those genes may have helped modern humans make the most out of the more limited sunlight available at higher latitudes in Eurasia, Capra said.
A separate study in 2017 similarly found that around 66% of Europeans carry a Neanderthal allele linked to a heightened risk of childhood sunburn and poor tanning ability.
Nicotine addiction
Some Neanderthal sequences may have completely different effects on our health today compared with when we first inherited them from our extinct cousins tens of thousands of years ago.
Neanderthal gene variants may influence our ability to quit smoking. A study published in 2016 in the journal Science found that people of European ancestry who carry a Neanderthal-specific mutation in a gene called SLC6A11, are more likely to become addicted to nicotine than those who don't. SLC6A11 codes for a protein that is involved in relaying signals between different parts of the brain.
Neanderthals didn't smoke tobacco so it is possible that this gene had a completely different beneficial effect when it was selected for during evolution, Capra told Live Science in 2016.
Fertility
Neanderthal DNA may make us more fertile, research indicates.
In 2020, a study published in the journal Molecular Biology and Evolution found that almost 1 in 3 women in Europe carry a Neanderthal gene variant that is associated with increased fertility, as well as being less likely to bleed during early pregnancy and less likely to experience miscarriages.
Specifically, these women inherited the receptor for the sex hormone progesterone from Neanderthals. In women, progesterone helps prepare the lining of the uterus for the possible implantation of a fertilized egg during reproduction. If fertilization is successful, progesterone also supports early embryonic development.
Depression risk
Some people could be more prone to developing depression if they carry specific Neanderthal DNA.
Generally, Neanderthal DNA is less commonly found in parts of our genomes that are involved in our brains, such as genes associated with cognitive function. However, in the 2016 Science study, scientists discovered Neanderthal DNA variants that are tied to mood disorders such as depression in people of European descent.
It's not clear why modern humans kept these genes, but from an evolutionary perspective, it could be tied to sunlight exposure, the authors hypothesized in their paper. In modern humans, depression risk is influenced by light levels, and Neanderthal gene variants are associated with ultraviolet protection, the authors suggested in the paper.
Generally, Neanderthal DNA is less commonly found in parts of our genomes that are involved in our brains, such as genes associated with cognitive function. However, in the 2016 Science study, scientists discovered Neanderthal DNA variants that are tied to mood disorders such as depression in people of European descent.
It's not clear why modern humans kept these genes, but from an evolutionary perspective, it could be tied to sunlight exposure, the authors hypothesized in their paper. In modern humans, depression risk is influenced by light levels, and Neanderthal gene variants are associated with ultraviolet protection, the authors suggested in the paper.
Viking disease risk
The development of Dupuytren's disease is strongly influenced by genetics, including several Neanderthal gene variants.
Gene variants inherited from Neanderthals may also increase the risk of developing a hand disorder called Dupuytren's disease or contracture.
Dupuytren's disease occurs when the tissue under the skin in the palm of the hand thickens and becomes less flexible. This can cause one or more fingers to contract and become frozen in a bent position. The disease is sometimes nicknamed "Viking disease" because it is very common in Northern European countries where the Vikings settled.
In a 2023 study of people who were primarily of European descent, scientists discovered 61 gene variants linked to a greater risk of Dupuytren's disease, three of which were of Neanderthal origin. These included the EPDR1 gene on chromosome 7 that is involved in muscle contractility.
Research has shown that Neanderthal DNA may impact our risk of developing autoimmune diseases, such as Crohn's disease, which affects the gastrointestinal tract.
Immune system-related genes inherited from Neanderthals may also contribute to autoimmune diseases, in which the body's immune system mistakenly attacks its own cells.
A 2014 study published in the journal Nature found that certain Neanderthal gene variants in modern humans are associated with the risk of developing two chronic disorders: lupus, which affects many parts of the body including the joints, skin and kidneys; and Crohn's disease, an inflammatory bowel disease.
The researchers found a variant tied to lupus in around 10% of Europeans and less than 1% of East Asians, while approximately 26% of Europeans and 8% of East Asians carried another variant linked to Crohn's disease.
https://www.livescience.com/health/genetics/10-unexpected-ways-neanderthal-dna-affects-our-health
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65,000 YEARS AGO, ALL NEANDERTHALS IN EUROPE DIED OUT EXCEPT FOR ONE LINEAGE
Pešturina Cave in Serbia, where a Neanderthal tooth that was genetically analyzed in the new study was found.
Before Neanderthals went extinct, they experienced a major upheaval that resulted in just one of their genetic lineages surviving in Europe and then expanding across the continent, a new study shows.
The findings, published March 23 in the journal PNAS, may shed light on what ultimately doomed the Neanderthals.
Neanderthals were among the closest relatives of modern humans (Homo sapiens), with their lineages diverging around 500,000 years ago. Although Neanderthals once ranged across Eurasia, they are generally thought to have gone extinct about 40,000 years ago.
DNA recovered from Neanderthal fossils can shed light not just on their extinction but on their history in general. In the new study, researchers examined DNA from mitochondria in cells, which help generate energy for the body, and get passed down from mothers to offspring.
The scientists gathered 10 mitochondrial DNA sequences from Neanderthals excavated from six archaeological sites in Belgium, France, Germany and Serbia. They analyzed them alongside 49 Neanderthal mitochondrial DNA sequences released in previous research.
The team found that in Europe, where Neanderthals ultimately died out, several mitochondrial DNA lineages existed until about 65,000 years ago. After this point, these groups were replaced by a single Neanderthal mitochondrial genetic lineage originating from southwestern France. These "Late Neanderthals" proceeded to disperse across Europe.
"This tells us there was this major disruption in Neanderthal history," study senior author Cosimo Posth, a paleogeneticist at the University of Tübingen in Germany, told Live Science. "There was really a genetic transformation.”
Posth noted that about 75,000 years ago, glaciers came to dominate Europe.
"We don't think our findings suggest that Neanderthals were migrating to the Mediterranean," he said. "We think Neanderthal groups in northern Europe perished, while a Neanderthal group that was already in southwestern France survived this climate change and then went on to expand across a broader region. Neanderthals had experienced multiple glaciations before, but the last one proved harsh on their survival."
The study also found that "there was a kind of genetic impoverishment among the Late Neanderthals," Posth said. "Since they appeared to emerge from this single group, their genetic diversity overall was reduced drastically compared to what came before — they were all extremely similar on a genetic level across Europe, from Spain to the Caucasus to northern Europe."
This low genetic diversity — which grew most pronounced about 42,000 years ago, shortly before Neanderthals generally died out — "might have played a role in their extinction," Posth noted. "We don't think there was a single reason the Neanderthals went extinct, but this lack of genetic diversity would have made them more predisposed to not really survive climatic changes and other disruptions.”
Likewise, Neanderthal groups in the Altai Mountains of Siberia were more closely related to each other than to European Neanderthals, and these Siberian Neanderthals also had low genetic diversity and lived in small, isolated groups, another March 23 study published in the journal PNAS found.
Despite this low genetic diversity, the Late Neanderthals in Europe appeared quite diverse across sites in terms of their artifacts and art. "So after the Neanderthals re-expanded across Europe, we think that Late Neanderthal groups were not highly connected with each other," Posth said. "This would have led to more inbred groups, explaining the low genetic diversity, but also more cultural and archaeological diversity, since these groups were isolated and so would have developed more specialized cultures."
"We've seen evidence that Neanderthal populations replaced each other, and this paper really creates a ground story as to why that might be — because Neanderthals went extinct in places all the time, and then other Neanderthal groups went in and recolonized the same places," Fernando Villanea, a population geneticist at the University of Colorado Boulder who was not involved in the study, told Live Science.
Future research could seek to test these findings by analyzing DNA from Neanderthal cell nuclei instead of their mitochondria, Posth said. However, this will be a major challenge, as DNA from nuclei is several hundred times less abundant than DNA from mitochondria in cells.
MICROPLASTICSARE EVERYWHERE AND WE BREATHE THEM IN — BUT THESE STEPS CAN HELP
When you wash or wear polyester clothing, countless minuscule fibers are released into the air.
I think of my home as a sanctuary away from the noise and pollution of the outside world, as it's the one environment I can control. But I may be too optimistic, as research shows that the air we breathe in our homes is filled with microplastics.
One study estimated that the average adult breathes in between 28,000-108,000 particles of plastic a day. Common culprits include synthetic clothing, household dust and even the vacuum you use to clean.
Holding your breath as you go about daily tasks is obviously not a realistic solution, but there are practical steps you can take to minimize your exposure.
Clouds of invisibly small microplastics concentrate in the air of our homes, and we could be breathing in hundreds of thousands to millions of them each year. A few small changes can help us reduce our exposure.
If you look at the labels of the clothes you threw on today, chances are at least some of them use synthetic fabrics. They're cheap, colorful and come in an endless array of textures, weights and degrees of stretch. But these convenient garments are also among the main culprits infusing the air in our homes with invisible pollution: microplastics.
When you wash and dry your polyblend jumper, for instance, shake it out, pull it on over your head, or just go about your day wearing it, countless minuscule fibers are released into the air. Take a breath, and a cloud of these tiny particles can flow into your airways.
We're just beginning to unravel the breadth of airborne microplastic exposure and its effect on our health, but what's already known is raising concern. (Read more on what microplastics do to our health.)
Scientists believe the majority of our exposure to microplastics happens when we're indoors. The good news is there are things we can do about it in our homes, from reconsidering the clothes and furnishings we buy, to changing the way we wash our clothes and clean our houses.
"Microplastics are everywhere, and there's no way you can avoid them," says Dana Barr, an exposure science professor at Emory University in Atlanta, the US. "But there are ways that you can significantly reduce your exposure over time, and it's mostly from behavioral change."
The air in our homes
Invisibly small fragments of plastic are all around us. They're expelled from virtually every product made of plastic (over 460 million tonnes of new plastic is produced every year). They make their way into our bodies via the food and water we consume, the products we use on our skin and the tiny particles we inhale when we breathe. (Read more on the microplastics in our food and how to eat less of them.)
Food and water was once thought to be the main way microplastics entered the body, but some scientists now believe that inhalation may in fact be the predominant route.
For instance, take a meal of filter-feeding shellfish like mussels, which can have high concentrations of microplastics. You're likely to inhale more plastics during the meal preparation than you eat from the food itself, according to one study. In countries where shellfish makes up a large part of the diet, you might expect to eat 4,620 particles per year. But you could be inhaling around three to 15 times more particles a year during mealtimes.
In developed countries, people spend about 90% of life indoors, which is one reason that the potential for microplastic inhalation is significantly higher compared to outdoors. A 2021 study examining airborne microplastics indoors and outdoors in China found that the concentration was eight times higher in indoor air. Even where natural fibers predominated over synthetics, and laundry – a considerable source of microplastics – was typically hung outside, microplastics were still at higher concentrations indoors.
"The fact that we're spending so much time indoors, and we're breathing the air indoors, means that we probably are vastly underestimating exposure," says Barr, who also is a director at the Hercules Exposome Research Center.
Just how many microplastics are in your home depends on where you live, what kinds of synthetic materials you have on your soft furnishings and in your wardrobe, what your flooring is made from, and how you clean and ventilate your space. Another study found that an individual in the US could be inhaling up to 22 million micro- and nanoplastics per year.
Wherever you live, microplastics are very likely to be in every room of your home. But where exactly do these fragments gather, and where do they come from?
Microplastics are found in our food and drink, in the air, and in toiletries and cosmetic products we use every day
When tiny fragments of plastic settle from the air, they often end up in household dust.
Even though dust settles, it can easily get kicked up into the air when disturbed by any sort of friction. Jeroen Sonke, a biogeochemist at the French National Center for Scientific Research who co-authored a recent study on indoor airborne microplastics, investigated the presence of small microplastics in the range of one to 10 micrometers, which penetrate deeper into the lungs than larger fragments.
Sonke and his colleagues looked inside three of their own apartments in Toulouse, France, to take samples, and collected further samples from inside two cars (where people in developed countries typically spend another 5% of their time). Sonke was surprised to find an average of more than 500 fragments in one cubic meter of air indoors, and more than 2,200 fragments inside the cabin of a car. He noted that these samples were mainly from stagnant air, but if people were present stirring up dust, the air would likely have many more microplastics.
For a baby crawling on the ground, their faces can be inches away from microplastic-filled dust. Sonke and his colleagues calculated the amount of microplastics an infant may inhale on an average day ranged between 19,000 and 75,000 particles in the 1-10 micrometer range. For adults, it was 28,000 to 108,000 particles a day.
These numbers come with a caveat: it remains challenging for scientists to unequivocally measure the amount of microplastics in the air. "There's no gold standard approach for measuring microplastics, and there may never be," says Douglas Walker, an associate professor of environmental health at Emory College, noting this makes it difficult to compare findings between studies.
And it's especially hard to measure smaller microplastics, which can find their way deeper into the lungs. Standard microscopes tend to have a lower limit of around 20 micrometers, though the technology is improving, Sonke notes. The method his team used (Raman microscopy) allowed them to get down to the 1 micrometer microplastic range for the first time.
Contamination also complicates the picture. The clothes scientists wear, which release clouds of microplastics, make it hard to get reliable results. Even the coating on latex gloves that scientists often wear during experimental work can accidentally influence samples, one study found.
Clothes, soft furnishings and carpets
Microplastics come in all different shapes and sizes, including spheres, flakes, foams and fragments. The predominant type of airborne microplastics come from textiles, such as the clothes we wear, the upholstered chairs and sofas we sit on, and the carpets we walk on.
"Indoors we do surround ourselves with lots of plastic materials, and things like upholstery, your furniture, your curtains, your bedding, your clothing, are all things that undergo daily wear and tear," says Stephanie Wright, a microplastics researcher and associate professor in the Faculty of Medicine at Imperial College London. "So literally as we use them, as we sit on them, as we move on them, as we wash them, as we hoover them – all these mechanical ways in which we wear them down generate microplastic as well."
These microplastics take the form of tiny fibers, and they're generated in the home more or less wherever plastic fibers are heated or come under friction.
Domestic laundry dryers do both to fabrics, releasing microplastics into the air of the room around them as they work. Washing machines are also a considerable source of microplastics, though here many of them drain out of the home to contaminate waterways.
Textile workers
The health risks from textile fibers come into sharp focus when looking at those who work with them day in, day out. A recent study analyzing airborne microplastic concentrations in several textile factories found consistently high concentrations of fine particles (0.5 micrometers and smaller) in the air and on factory floors. Some studies have found fragments of that size are responsible for health risks, including respiratory issues such as asthma, lung tissue damage and endocrine disruption.
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If you own your washing machine, you can purchase a filter for your washing machine that can reduce up to 90% of microfibers from wastewater. Annelise Adrian, a senior program officer with the plastics and material science team at World Wildlife Fund, also recommends doing larger loads of laundry to reduce friction between clothes during the process.
Wright adds that alongside technological innovations, we can change our habits too. "You can try and be as efficient as possible and only wash clothes when you need to," she says. When weather and access permit, you could consider drying your clothes outside, she adds.
Switching to clothes made exclusively from natural materials, such as cotton, wool or linen, can also reduce your exposure to fibrous microplastics. Unlike plastic, natural fibers break down in the body. However, they tend to be pricier than synthetic clothing and require more land and other resources to make. Cotton fibers, for example, require substantially more water to produce than synthetic fibers.
If you are going to wear synthetic clothes, buying used, second-hand garments may also limit microplastic exposure, although scientists are somewhat divided on this. "Some are saying that used clothes have already shed their loose fibers and are less prone to shedding," says Adrian. "However, others argue that used clothes can accumulate more microplastics from all the washes they've undergone, and fibers can break and weaken over time."
Instead, buying used natural-fiber clothes, such as organic cotton or organic wool products, would be "the gold standard", says Adrian.
After minimizing the synthetic textiles around you, a good next step is to try to remove the plastic dust in your home, says Wright.
Vacuuming
A thorough vacuum can suck up microplastics that have settled on your floors and furniture, but it can simultaneously send particles back into the air as you clean. You'll also get a face full when you empty the bag or canister into the bin, says Barr.
"What [vacuuming] does do is it resuspends particles that it's not picking up," says Barr. She suggests wearing an N95 mask while vacuuming or dusting may help protect you. Wright also recommends vacuuming and emptying the dust from the machine in a well-ventilated space.
Vacuums with high-efficiency particulate air (Hepa) filters and a sealed system can help limit your exposure to airborne microplastics while you clean. Their filters are designed to trap smaller particles and prevent them from being released. But they're not perfect devices either; even the best Hepa-filtered vacuum will still resuspend some microplastic particles, says Barr.
Adrian suggests coupling vacuuming with other ventilation methods to lower airborne exposure. "If you are cleaning, have a source of ventilation, like an air filter, or open your window."
However, resuspension of microplastics during vacuuming is thought to be a temporary problem. A study across 29 countries found that regular vacuuming lowered microplastic levels. Vacuum cleaners that are properly maintained, with their filters and dust collectors regularly emptied and cleaned, also help to reduce air pollution indoors more generally.
"You're getting rid of [the microplastic], essentially, before it has chance to become airborne again," says Wright.
Mopping and wiping hard surfaces with a wet cloth before you vacuum can help tamp down microplastics so fewer become airborne, says Barr. However, be wary of the products you use to wipe down surfaces; some cleaning products, such as wipes and sponges, can also generate microplastics.
Air filters and air conditioning
It may be impossible to remove microplastics from the air completely, but some simple home devices can help limit your exposure. Hepa air filters are designed to theoretically remove at least 99.97% of airborne particles around 0.3 micrometers (typically the trickiest size to filter). One study that analyzed micro- and nanoplastics alongside other air pollution found that a true Hepa filter could remove over 99% of nanoparticles from the atmosphere.
Not all Hepa air filters are created equal, however. Even if they've met the Hepa standards, their construction and functionality could impact how well they capture plastic particles in the average home. Considering that, if you're going to invest in one, Barr suggests models that have numerous filtering stages.
"They have some coarse areas and then fine filtration areas. The more of those filters you have, the more they're stacked, the better off you're going to be, because you're going to be able to filter out multiple sizes of particles," Barr says. Air filtration systems like this tend to have a larger capacity, allowing for a greater surface area to absorb more particles in a range of sizes.
Air conditioning, meanwhile, may not be so helpful for reducing microplastics. Microplastics accumulate on air conditioning units, one study found, and could distribute microplastics around the room when operating. Strong air conditioning can even increase the emission of microplastics from textiles. A study in Colombia found higher concentrations of microplastics in rooms with air conditioning than those without.
Health impacts
Microplastics are present in our bodies in abundance. Exactly what these microplastics do once they are inside us is less clear. Some microplastic particles may settle in the mucus lining the airways and be cleared out without entering the body's tissues. Some, however, may travel deeper. One study of different human tissues found the highest concentration of microplastics was in the lungs.
Smaller microplastics of less than 20 micrometers can cause inflammation, while particles smaller than five micrometers can make their way inside cells and accumulate in different organs. These smaller particles are not filtered by the nose but rather travel down to the lungs where they become lodged. In mice, one study found that inhaled microplastics traveled to the thymus, spleen, testes, liver, kidneys and brain within three days, and caused inflammation in multiple organs.
"Fibers have the worst impact on health when inhaled," says Adrian. "The fiber shape enhances retention of toxins."
Fiber microplastics can also go deep into your body, past your lungs, into your bloodstream and lymphatic system, where they can interfere with cellular biology. Compared with other shapes, longer fibers may also persist longer in the body, notes Adrian.
"The thinner the fiber, and the smaller, on average, the fiber is, then the more likely it is to penetrate deeper into our airways, and deeper into the lung," says Wright.
Based on what we know from other types of tiny fibers, those dimensions are problematic, she says, based on what we know about mineral fibers such as asbestos or carbon nanotubes. "We know that those fibers – small enough to javelin down into the air sacs at the end of our airways – are problematic.”
For microplastic fibers, the picture is still unclear, says Wright. "Would they cause the same effect? Or the fact that they're flexible, whereas mineral fibers are very rigid, does that make [microplastics] less toxic, less harmful?"
Beyond their potential to interfere with tissues, there's also the concern that microplastics often come with company. They are home to a broad range of bacteria, and may carry other contaminants too. It's been suggested that microplastics might act to amplify the toxicity of other pollutants in the environment. This field of research, however, is still in its early days, and the full effects of microplastics on the body are still not yet understood.
To solve the microplastic pollution crisis will take a lot more than changes within the home – there are plenty of broader sustainability concerns too. If moving to replace synthetic fibers in your home with natural fibers, for instance, there's also the greater water and land use from organic cotton use to think about. Or if choosing to ventilate your home more to usher away microplastics, that pollution is only being pushed outdoors. Short of systemic change and a global reduction from the 460 million tons of plastic made each year, there's only so much individuals can do.
"It's tricky, isn't it?" Wright concedes. "Because I feel like in these scenarios, it's pick your battles."
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ending on beauty:
CROSSING THE BAR
Sunset and evening star,
And one clear call for me!
And may there be no moaning of the bar,
When I put out to sea,
But such a tide as moving seems asleep,
Too full for sound and foam,
When that which drew from out the boundless deep
Turns again home.
Twilight and evening bell,
And after that the dark!
And may there be no sadness of farewell,
When I embark;
The flood may bear me far,
I hope to see my Pilot face to face
When I have crossed the bar.
~ Tennyson
