This article was originally published in Knowable Magazine.

Shrubbery, toolsheds, basements—these are places one might expect to find spiders. But what about the beach? Or in a stream? Some spiders make their homes near or, more rarely, in water: tucking into the base of kelp stalks, spinning watertight cocoons in ponds or lakes, hiding under pebbles at the seaside or along a creek bank.

“Spiders are surprisingly adaptable, which is one of the reasons they can inhabit this environment,” says Ximena Nelson, a behavioral biologist at the University of Canterbury in Christchurch, New Zealand.

Finding aquatic or semiaquatic spiders is difficult work, Nelson says: She and a student have spent four years chasing a jumping spider known as Marpissa marina around the pebbly seaside beaches it likes, but too often, as soon as they manage to find one, it disappears under rocks. And sadly, some aquatic spiders may disappear altogether before they come to scientists’ attention, as their watery habitats shrivel because of climate change and other human activities.

What scientists do know is that dozens of described spider species spend at least some of their time in or near the water, and more are almost surely awaiting discovery, says Sarah Crews, an arachnologist at the California Academy of Sciences, in San Francisco. It also appears that spiders evolved aquatic preferences on several distinct occasions throughout the history of this arthropod order. Crews and colleagues surveyed spiders and reported in 2019 that 21 taxonomic families are associated with aquatic habitats, suggesting that the evolutionary event occurred multiple independent times. Only a swashbuckling few—not even 0.3 percent of described spider species—are seashore spiders; many more have been found near fresh water, Nelson says.

It’s not clear what would induce successful land-dwelling critters to move to watery habitats. Spiders, as a group, probably evolved about 400 million years ago from chunkier creatures that had recently left the water. These arthropods lacked the skinny waist sported by modern spiders. Presumably, the spiders that later returned to a life aquatic were strongly drawn by something to eat there, or driven by unsafe conditions on land, says Geerat Vermeij, a paleobiologist and distinguished professor at UC Davis—because water would have presented major survival challenges.

“Since they depend on air so much, they are severely limited in whether they can do anything at all when they are submerged, other than just toughing it out,” Vermeij says. Newly aquatic spiders would have had to compete with predators better adapted to watery conditions, such as crustaceans, with competition particularly fierce in the oceans, Vermeij says. And if water floods a spider’s air-circulation system, it will die, so adaptations were obviously needed.

But spiders as a group already possess several water-friendly features, Crews suggests. They have waxy, water-repellent exteriors, often covered in hairs that conveniently trap air bubbles. Even having eight legs is helpful, Nelson says: Spiders can distribute their weight nicely while they skitter across a water surface, or use their octet of appendages to row along.

[Read: The spiders that choose death]

Some spiders take their aquatic adaptations to the next level, though. Consider the diving-bell spider, Argyroneta aquatica, an overachieving arachnid that is the only one known to do it all underwater: breathe, hunt, dine on insects and their larvae, and make spiderlings. Found in fresh water in Europe and parts of Asia, it spins a silken underwater canopy and brings air bubbles from the surface to its submerged home via its body hairs. When it goes out, it carries a smaller air bubble, like a little scuba tank, on its back.

Seashore spiders face particularly daunting conditions, says Nelson, who co-authored an article about adaptations of marine spiders for the 2024 Annual Review of Entomology. “There’s a splash zone,” she says. “It’s kind of a wild environment.” A spider might be baking in the hot sun one minute and drenched in chilly salt water the next. Some spiders migrate up and down their beaches with the tides; Nelson speculates that they monitor lunar cycles to anticipate when to move.

Other seashore spiders spin watertight nests where they hide out for hours while the tide is in. M. marina, for example, seeks seashells with nice, concave spaces in which to spin safe tents. Another spider, Desis marina, hides in holdfasts where bull kelp attaches to rocks, lining the holdfast’s interior with silk to create an air-filled pocket and staying submerged for as long as 19 days. D. marina emerges only when the tide is going out, to hunt for invertebrates like shrimp.

A spider that’s even occasionally submerged in salt water or that eats briny seafood will also have to maintain proper internal salt levels. “Presumably, they will be able to concentrate the salt somehow and then poo it out,” Nelson says. Scientists don’t know how marine spiders pull this off. And at least one intertidal-zone spider, Desis formidabilis of South Africa’s cape, comfortably maintains an interior salt concentration much like the crustaceans it eats, according to a 1984 study. (Freshwater species also probably require adaptations because their insides must stay saltier than their surroundings or food, Vermeij speculates.)

When a spider hides out with a limited air supply for days or weeks at a time, oxygen levels also may become a crucial issue. Intriguingly, researchers have identified gene variants within the oxygen-guzzling, energy-making mitochondria of aquatic spiders that may help them cope with low-oxygen environments. These changes mirror beneficial changes to mitochondrial genes in birds that live in high-altitude, low-oxygen environments.

In another study, researchers investigated the genes used in the silk glands of aquatic and land spiders. They found that water-spider silk seems to have a high proportion of water-repelling amino acids—which might also be an adaptation, they suggest.

But all the adaptations in the world might not be enough to save some water spiders. Nelson’s M. marina, for example, seems to be very particular about the beaches it occupies. The pebbles must be just right, not too big or small. If sea-level rise inundates M. marina’s beaches, it’s possible the spiders will have nowhere else to go, Nelson says. “So those spiders will be lost.”

Marco Isaia, an arachnologist at the University of Turin, in Italy, investigated the wetland habitats of the diving-bell spider and the fen raft spider, Dolomedes plantarius. As wetlands continue to disappear, the habitats available to each species will contract by more than 25 percent over a decade, and their ideal ranges will move northward, Isaia and colleagues predicted in a 2022 study. It would be difficult for the spiders to cross dry land for new wetlands, and Northern European winters might prove too cold anyway. “The loss and degradation of wetland habitats is expected to have serious impacts on their survival,” Isaia says, “and an increase in their extinction risk.”

Given these risks, some aquatic spiders might go the way of the dodo before science gets a handle on them. “I suspect in every rocky bed of beach or river, there are probably spiders that we just don’t know exist there,” Nelson says. “Because they’re hiding.”

This is an edition of The Atlantic Daily, a newsletter that guides you through the biggest stories of the day, helps you discover new ideas, and recommends the best in culture. Sign up for it here.

Welcome back to The Daily’s Sunday culture edition, in which one Atlantic writer or editor reveals what’s keeping them entertained. Today’s special guest is Kevin Townsend, a senior producer on our podcast team. He currently works on the Radio Atlantic podcast and has helped produce Holy Week—about the week after Martin Luther King Jr.’s assassination—and the Peabody-winning Floodlines, which explores the devastation of Hurricane Katrina.

Kevin enjoys reading Philip Levine’s poems and visiting the National Gallery of Art, in Washington, D.C., where he can sit with Mark Rothko’s large-scale works. He’s also a Canadian-punk-music fan—Metz is one of his favorite bands—and a self-proclaimed Star Trek nerd who’s excited to binge the final season of Star Trek: Discovery.

First, here are three Sunday reads from The Atlantic:

Amanda Knox: “What if Jens Söring actually did it?” How Daniel Radcliffe outran Harry Potter The blindness of elites

The Culture Survey: Kevin Townsend

A quiet song that I love, and a loud song that I love: In college, I developed a steady rotation of quiet songs that didn’t distract me while I was studying. Artists such as Tycho and Washed Out were some of my favorites.

Recently, I’ve been into Floating Points, the moniker for Samuel Shepherd, a British electronic-music producer. I could recommend his Late Night Tales album or Elaenia, but the one that stands out most to me is his collaborative album, Promises, featuring the saxophonist Pharoah Sanders and the London Symphony Orchestra. It’s a gorgeous, layered work that’s best listened to all the way through—but if you’re pressed for time, “Movement 6” is an exceptional track.

As for a loud song, one of my favorite bands is the Canadian punk trio Metz. I’ve had “A Boat to Drown In” on heavy rotation for the past year. It doesn’t have the thrumming precision of their earlier singles such as “Headache” and “Wet Blanket,” but the song is a knockout every time. Metz just released a new record, Up on Gravity Hill, that I’m excited to get lost in.

The last museum or gallery show that I loved: “Mark Rothko: Paintings on Paper,” an exhibition at the National Gallery of Art, showcased some of the abstract painter’s lesser-known works. The show closed recently, but the museum’s permanent collection features a good number of his works, including some of his famous color-field paintings. The National Gallery is also home to many pieces from the collection of the now-closed Corcoran Gallery of Art, and they’re worth a visit—especially the Hudson River School paintings, which must be seen in person in all of their maximalist glory.

Best novel I’ve recently read, and the best work of nonfiction: A few months ago, on my honeymoon, I reread No Country for Old Men. It’s far from a romantic beach read, but few writers are as tersely gripping as Cormac McCarthy. The Coen brothers’ film adaptation is fantastic, but the novel—published in 2005, two years into the Iraq War—encompasses a wider story about generations of men at war. It’s worth reading even if you’ve seen the movie.

I also brought with me a book I’d long meant to read: Lulu Miller’s Why Fish Don’t Exist. Part science history, part memoir, the book is mostly a biography of David Starr Jordan, Stanford University’s first president and a taxonomist who catalogued thousands of species of fish. It’s a unique and remarkable read that I can’t recommend highly enough. Fundamentally, it’s about our need for order—in our personal world, and in the natural world around us.

Miller’s book reminds me of a recent Radio Atlantic episode that I produced, in which Atlantic staff writer Zoë Schlanger discusses her new book, The Light Eaters, about the underappreciated biological creativity of plants. Miller and Schlanger both examine and challenge the hierarchies we apply to the natural world—and why humanity can be better off questioning those ideas.

A poem, or line of poetry, that I return to: My favorite poet is Philip Levine. His work is spare and direct, alive with love for the unsung corners of America and the people who inhabit them. Levine lived in Detroit during the Depression and spent more than three decades teaching in Fresno. Having grown up in Pittsburgh and moved to California as a teenager, I connected easily with the world he saw.

“What Work Is” and “The Simple Truth” are two of his poems that I often return to, especially for the final lines, which feel like gut punches. [Related: An interview with Philip Levine (From 1999)]

Speaking of final-line gut punches, the poem (and line) that I think of most frequently is by another favorite poet of mine: the recently departed Louise Glück. “Nostos,” from her 1996 book, Meadowlands, touches on how essential yet fragile our memories are, and there’s a haunting sweetness to its last line: “We look at the world once, in childhood. / The rest is memory.”

The television show I’m most enjoying right now: It’s May, so, honestly: the NHL playoffs. (And it’s been a great year for hockey.) But when it comes to actual television, I’m excited to binge the fifth and final season of Star Trek: Discovery.

It’s bittersweet that the series is ending. Sonequa Martin-Green gives an Emmy-worthy lead performance, but for all of the show’s greatness, it can lean a bit too much into space opera, with the galaxy at stake every season and a character on the verge of tears every episode. Trek is usually at its best when it’s trying to be TV, not cinema. (And that’s including the films—Star Trek II: The Wrath of Khan succeeded by essentially serving up a movie-length episode.) [Related: A critic’s case against cinema]

Being a friend of DeSoto, I want to give another Trek-related recommendation: The Greatest Generation and Greatest Trek podcasts, which go episode by episode through the wider Trek Industrial Complex. The humor, analysis, and clever audio production elevate the shows above the quality of your typical rewatch podcast. I came to The Greatest Generation as an audio-production and comedy nerd, and it turned me into a Trek nerd as well. So be warned.

Something I recently rewatched, reread, or otherwise revisited: The Hunt for Red October. Somehow, it gets better with every watch. “Give me a ping, Vasili. One ping only, please.”

The Week Ahead

Kingdom of the Planet of the Apes, an action sci-fi movie about a young ape who must face a tyrannical new ape leader (in theaters Friday) Dark Matter, a mystery series, based on the best-selling novel, about a man who is pulled into an alternate reality and must save his family from himself (premieres Wednesday on Apple TV+) First Love, a collection of essays by Lilly Dancyger that portray women’s friendships as their great loves (out Tuesday)

Essay

Illustration by Ben Kothe / The Atlantic. Source: Courtesy of Elena Dudum.

I Am Building an Archive to Prove That Palestine Exists

By Elena Dudum

My father collects 100-year-old magazines about Palestine—Life, National Geographic, even The Illustrated London News, the world’s first graphic weekly news magazine. For years, he would talk about these mysterious documents but rarely show them to anyone. “I have proof,” he would say, “that Palestine exists.”

His father, my paternal grandfather, whom I called Siddi, had a similar compulsion to prove his heritage, though it manifested differently. Siddi used to randomly recite his family tree to my father when he was a child. As if answering a question that had not been asked, he would recount those who came before him …

Although my American-born father didn’t inherit Siddi’s habit of reciting his family tree, he did recite facts; he lectured me about Palestine ad nauseam in my youth, although he had not yet visited. Similar to his father’s, these speeches were unprompted. “Your Siddi only had one business partner his entire life,” he would say for the hundredth time. “And that business partner was a rabbi. Palestinians are getting pitted against the Jews because it’s convenient, but it’s not the truth.”

Read the full article.

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Humans have always been explorers. For better or worse, something in our collective makeup seems to push us to discover new things, understand the enigmatic, or reach past the limits of what we imagine is possible. Some people dream about what the cosmos could contain; scientists launch probes into space, and astronauts travel beyond Earth’s atmosphere. Others go on life-threatening quests, such as climbing the planet’s tallest peaks and diving into the sea’s deepest trenches, to tap into the wonder, fear, and awe that come from experiencing—and surviving—the places on Earth most hostile to human life.

The six books below reflect on what drives our species to seek out the uncharted and unknown. In each, what propels an individual’s desire to expand their experiences differs; some stories follow people yearning for adventure or to set a record, while other protagonists turn to exploration when they want to run away from something. No matter where these books take us, whether they cover searching for life beyond our planet or diving miles deep into the ocean to discover ecosystems heretofore unknown, their pages bring readers along for the ride.

Gallery Books

Contact, by Carl Sagan

In Sagan’s 1985 novel, the astronomer Ellie Arroway is the leader of a scientific endeavor called Project Argus, a network of radio telescopes that picks up a message from an extraterrestrial source. The missive includes blueprints to build a machine that can take a group of humans … somewhere. Sagan’s story weaves Ellie’s personal life, particularly her relationship with her parents, together with Earth’s many competing efforts to build (or destroy) a working version of this machine. Though the novel doesn’t shy away from humanity’s propensity to sow discord and violence, Sagan’s story has a through line of hope—Contact is ultimately about how people’s tendency to seek the unknowable can lead them to better understand themselves and others. By the end of the novel, Ellie—who has traveled to the stars and back—realizes that “for small creatures such as we the vastness is bearable only through love.” This message resonates nearly four decades later, as humans wade farther and farther into the galaxy.

Doubleday

The Underworld: Journeys to the Depths of the Ocean, by Susan Casey

For all of humanity’s stargazing, the deepest trenches of Earth’s oceans remain relatively unexplored. Many people consider the sea “the earth’s haunted basement—sinister, shrouded in blackness, spewing molten rock and poisonous gases, a den of freaky beings and hoary specters—and they would rather stay upstairs,” Casey writes in her book about those who do seek to journey to the bottom of the sea, where “intraterrestrial” life thrives. Casey herself is one of those people, and in The Underworld, she showcases others whose vocations send them into the ocean’s depths. But the book isn’t only about humans: Equal time is given to the creatures that live down there—including animals that aquanauts have given flippant monikers to, such as assfish, snailfish, weirdfish, and rattails—and underwater natural phenomena, such as black smoker hydrothermal vents, chimneylike structures that spew a sulfide-rich “smoke” into the water. Through Casey’s research, interviews, and firsthand experience, readers journey to the abyssal and hadal zones of the ocean, which run 10,000 to 36,000 feet deep, and get to share the “alchemical mix of wonder and fear” the author finds there.

Read: The Titanic sub and the draw of extreme tourism

One World

Lone Women, by Victor LaValle

Exploration isn’t always about running toward something—at times, it’s about running away from something else. Lone Women uses the trappings of the American West, a complicated, enduring cultural symbol of a supposedly untouched frontier, to delve into the human tendency to try to escape the past. It follows Adelaide Henry, a Black woman who leaves her family's California farm in 1915 under violent circumstances and lugs a mysterious trunk to Montana, where the U.S. government is offering free land to those who homestead there. The trunk’s undisclosed, possibly supernatural contents disturb Adelaide, and seem directly related to what she’s trying to leave behind. Over the course of the book, we see her failed attempt to shut that part of her past away as she tries to build a life in the brutal landscape of the Great Plains, a place that can destroy anyone who’s unprepared or without friends—or be a refuge for those looking to build a new home with space for the love, and suffering, that comes with living.  

Read: The ‘curious’ robots searching for the ocean’s secrets

Vintage

The River of Doubt: Theodore Roosevelt’s Darkest Journey, by Candice Millard

Teddy Roosevelt lived his life by fighting his way through it, pummeling any hardships or setbacks with relentless action and an indomitable force of will. In 1912, he lost a presidential election that would have given him a third term. The defeat devastated him, and—as he was wont to do—he sought an endeavor that would put his mental and physical limits to the test. He decided on an expedition to an unmapped expanse of land in South America, which to North Americans represented an alluring, seemingly impenetrable wilderness. Once he landed in Brazil, he was persuaded to explore an Amazonian tributary ominously and aptly called the River of Doubt. “If it is necessary for me to leave my bones in South America, I am quite ready to do so,” he wrote. Roosevelt did, in fact, almost die on that trek. He and the men who accompanied him were, “for all their own experience and knowledge, vulnerable outsiders,” Millard writes. She goes on to describe how their hubris on that journey made them “clumsy, conspicuous prey” at the mercy of not only the Cinta Larga tribe, whose members shadowed them throughout and could have killed them easily if they’d decided to, but also the flora and fauna they knew little about. The River of Doubt is a riveting look at how exploration can be laden with arrogance and ignorance. Millard vividly recounts how Roosevelt brought both with him into the Amazon, and how much both cost him.

Read: The difference between exploring and tourism

Vintage

Into the Wild, by Jon Krakauer

In April 1992, a 24-year-old man named Chris McCandless walked into the wilds three hours outside Fairbanks, Alaska, intent to live off the land without any modern conveniences. “I don’t want to know what time it is. I don’t want to know what day it is or where I am. None of that matters,” he told the man who dropped him off at the edge of the bush. McCandless never made it out—he died in the home he’d made in an abandoned bus sometime that August. His journey was reckless—he was unprepared in terms of both supplies and the knowledge of how to survive. His story, which Krakauer first recounted in an article for Outside magazine, angered many: How could McCandless have been so foolhardy? (Krakauer’s account also doesn’t capture all of his subject’s life: Chris’s sister Carine alleged years later that their parents had physically and mentally abused both children; they called her memoir “fictionalized.”) McCandless, however, was confounded by people passively staying within the confines of a civilization that he found crushing. Krakauer’s recounting of his final months is captivating, giving readers a window into McCandless’s mentality; it is a tragic portrait of a man whose urge to escape into nature was so strong and alluring that, decades later, the circumstances of his death have morphed into legend.

William Morrow

Seveneves, by Neal Stephenson

At certain moments, the impetus to go somewhere new isn’t about gaining knowledge or traveling simply for the novelty: Sometimes, it’s the only way to survive. In Seveneves, the moon explodes, making Earth uninhabitable for humans. The bulk of the story centers on the 1,500 or so people who struggle in the aftermath of the disaster, living initially in ad hoc habitats built around the International Space Station. Most of them die in these first years, destroyed by mounting internal discord and by the struggle to gain the basic resources—water, air, food—required for life. Stephenson goes deep into the science of their attempts to make it, and the book will fire up anyone who, for example, wants to know in detail how humans might be able to capture water from a passing ice comet. Ultimately, only seven women able to bear children remain, and they later set up base in a cleft of the broken moon. Then, about two-thirds of the way through the book, the action leaps 5,000 years into the future, where a civilization with billions of genetically altered humans seeks to reclaim Earth. Stephenson’s considerable extrapolations about what humans—or their genetically altered future descendants—will do to survive make the novel a fun, philosophical, and surprisingly hopeful read.

For a long time, having children has been a young person’s game. Although ancient records are sparse, researchers estimate that, for most of human history, women most typically conceived their first child in their late teens or early 20s and stopped having kids shortly thereafter.

But in recent decades, people around the world, especially in wealthy, developed countries, have been starting their families later and later. Since the 1970s, American women have on average delayed the beginning of parenthood from age 21 to 27; Korean women have nudged the number past 32. As more women have kids in their 40s, the average age at which women give birth to any of their kids is now above 30, or fast approaching it, in most high-income nations.

Rama Singh, an evolutionary biologist at McMaster University, in Canada, thinks that if women keep having babies later in life, another fundamental reproductive stage could change: Women might start to enter menopause later too. That age currently sits around 50, a figure that some researchers believe has held since the genesis of our species. But to Singh’s mind, no ironclad biological law is stopping women’s reproductive years from stretching far past that threshold. If women decide to keep having kids at older ages, he told me, one day, hundreds of thousands of years from now, menopause could—theoretically—entirely disappear.

Singh’s viewpoint is not mainstream in his field. But shifts in human childbearing behavior aren’t the only reason that menopause may be on the move. Humans are, on the whole, living longer now, and are in several ways healthier than our ancient ancestors. And in the past few decades, especially, researchers have made technological leaps that enable them to tinker like never before with how people’s bodies function and age. All of these factors might well combine to alter menopause’s timeline. It’s a grand experiment in human reproduction, and scientists don’t yet know what the result might be.

So far, scientists have only scant evidence that the age of onset for menopause has begun to drift. Just a few studies, mostly tracking trends from recent decades, have noted a shift on the order of a year or two among women in certain Western countries, including the U.S. and Finland. Singh, though, thinks that could be just the start. Menopause can come on anywhere from a person’s 30s to their 60s, and the timing appears to be heavily influenced by genetics. That variation suggests some evolutionary wiggle room. If healthy kids keep being born to older and older parents, “I could see the age of menopause getting later,” Megan Arnot, an anthropologist at University College London, told me.

Singh’s idea assumes that menopause is not necessary for humans—or any animal, for that matter—to survive. And if a species’ primary directive is to perpetuate itself, a lifespan that substantially exceeds fertility does seem paradoxical. Researchers have found lengthy post-reproductive lifespans in only a handful of other creatures—among them, five species of toothed whales, plus a single population of wild chimpanzees. But women consistently spend a third to half of their life in menopause, the most documented in any mammal.

In humans, menopause occurs around the time when ovaries contain fewer than about 1,000 eggs, at which point ovulation halts and bodywide levels of hormones such as estrogen plummet. But there’s no biological imperative for female reproductive capacity to flame out after five decades of life. Each human woman is born with some 1 to 2 million eggs—comparable to what researchers have estimated in elephants, which remain fertile well into their 60s and 70s. Nor do animal eggs appear to have a built-in expiration date: Certain whales, for instance, have been documented bearing offspring past the age of 100.

[Read: Why killer whales (and humans) go through menopause]

This disconnect has led some researchers to conclude that menopause is an unfortunate evolutionary accident. Maybe, as some have argued, menopause is a by-product of long lifespans evolving so quickly that the ovaries didn’t catch up. But many women have survived well past menopause for the bulk of human history. Singh contends that menopause is a side effect of men preferring to mate with younger women, allowing fertility-compromising mutations to accumulate in aged females. (Had women been the ones to seek out only younger men, he told me, men would have evolved their own version of menopause.) Others disagree: Arnot told me that, if anything, many of today’s men may prefer younger women because fertility declines with age, rather than the other way around.

But the preponderance of evidence supports menopause being beneficial to the species it’s evolved in, including us, Francisco Úbeda de Torres, a mathematical biologist at Royal Holloway, University of London, told me. Certainly, menopause was important enough that it appears to have arisen multiple times—at least four separate times among whales alone, Samuel Ellis, a biologist at the University of Exeter, told me.

One of the most prominent and well-backed ideas about why revolves around grandmothering. Maybe menopause evolved to rid older women of the burden of fertility, freeing up their time and energy to allow them to help their offspring raise their own needy kids. In human populations around the world, grandmother input has clearly boosted the survival of younger generations; the same appears to be true among orcas and other toothed whales. Kristen Hawkes, an anthropologist at the University of Utah, argues that the influence of menopausal grandmothering was so immense that it helped us grow bigger brains and shaped the family structures that still govern modern societies; it is, she told me, sufficient to explain menopause in humans, and what has made us the people we are today.

[From the October 2019 issue: The secret power of menopause]

Some researchers suspect that menopause may have other perks. Kevin Langergraber, an ecologist at Arizona State University, points out that certain populations of chimpanzees can also live well past menopause, even though their species doesn’t really grandmother at all. In chimpanzees and some other animals, he told me, menopause might help reduce the competition for resources between mothers and their children as they simultaneously try to raise young offspring.

Regardless of the precise reasons, menopause may be deeply ingrained in our lineage—so much so that it could be difficult to adjust or undo. After all this time of living with an early end to ovulation, there is probably “no single master time-giver” switch that could be flipped to simply extend human female fertility, Michael Cant, an evolutionary biologist at the University of Exeter, told me.

Perhaps, though, menopause’s timeline could still change—not on scales of hundreds of thousands of years, but within generations. Malnutrition and smoking, for instance, are linked to an early sunsetting of menses, while contraceptive use may push the age of menopause onset back—potentially because of the ways in which these factors can affect hormones. Menopause also tends to occur earlier among women of lower socioeconomic status and with less education. Accordingly, interventions as simple as improving childhood nutrition might be enough to raise the average start of menopause in certain parts of the world, Lynnette Sievert, an anthropologist at the University of Massachusetts at Amherst, told me.

[Read: Why so many accidental pregnancies happen in your 40s]

Changes such as those would likely operate mostly on the margins—perhaps closing some of the gaps between poorer and richer nations, which can span about five years. Bigger shifts, experts told me, would probably require medical innovation that can slow, halt, or even reverse the premature aging of the ovaries, and maintain a person’s prior levels of estrogen and other reproductive hormones. Kara Goldman, an obstetrician-gynecologist and a reproductive scientist at Northwestern University, told me that one key to the ovarian fountain of youth might be finding drugs to preserve the structures that house immature eggs in a kind of dormant early state. Other researchers see promise in rejuvenating the tissues that maintain eggs in a healthy state. Still others are generating cells and hormones in the lab in an attempt to supplement what the aging female body naturally loses. Deena Emera, an evolutionary geneticist at the Buck Institute for Research on Aging, in California, thinks some of the best inspiration could come from species that stay fertile very late into life. Bowhead whales, for instance, can reproduce past the age of 100—and don’t seem to succumb to cancer. Maybe, Emera told me, they’re especially good at repairing DNA damage in reproductive and nonreproductive cells alike.

Some women may welcome an extended interval in which to consider having kids, but Goldman and Emera are most focused on minimizing menopause’s health costs. Studies have repeatedly linked the menopause-related drop in hormones to declines in bone health; some research has pointed to cardiovascular and cognitive issues as well. Entering menopause can entail years of symptoms such as hot flashes, urinary incontinence, vaginal dryness, insomnia, and low libido. Putting all of that off, perhaps indefinitely, could extend the period in which women live healthfully, buoyed by their reproductive hormones.

[Read: Women in menopause are getting short shrift]

Extending the ovaries’ shelf life won’t necessarily reverse or even mitigate menopause’s unwanted effects, Stephanie Faubion, the director of Mayo Clinic’s Center for Women’s Health, told me. Plus, it may come with additional risks related to later-in-life pregnancies. It could also raise a woman’s chances of breast or uterine cancer, blood clots, and stroke, Jerilynn Prior, an endocrinologist at the University of British Columbia, told me. And putting off menopause may also mean more years of menstruation and contraception, a prospect that will likely give many women pause, says Nanette Santoro, an obstetrician-gynecologist and a reproductive scientist at the University of Colorado School of Medicine.

But several researchers think some tweaking is worth a shot. Even if menopause once helped our species survive, Goldman said, “it’s hard to imagine” that’s still the case. Evolution may have saddled us with an odd misalignment in the lifespans of the ovaries and the other organs they live alongside. But it has also equipped us with the smarts to potentially break free of those limits.