Books about the pandemic. Books about the ancient past. Books about outer space. These were a few of Science News staff’s favorite reads. If your favorite didn’t make this year’s cut, let us know what we missed at feedback@sciencenews.org.

Vagina Obscura
Rachel E. Gross
W.W. Norton & Co.
$30

For centuries, scientists (mostly males) have ignored female biology, and women’s health has suffered. But researchers are finally paying attention, as Gross explains in this fascinating tour of what little is known about female anatomy (SN: 4/9/22, p. 29).

The Song of the Cell
Siddhartha Mukherjee
Scribner
$32.50

Patient stories and conversations with scientific luminaries enliven this tale of cell biology’s past, present and future, and how advances in the field have reshaped medicine (SN: 11/5/22, p. 28).

Breathless
David Quammen
Simon & Schuster
$29.99

In this portrait of the coronavirus and the scientists who study it, Quammen investigates some of the most pressing questions about the pandemic, including whether or not the coronavirus could have accidentally escaped from a lab (SN: 9/24/22, p. 28).

Virology
Joseph Osmundson
W.W. Norton & Co.
$16.95

This wide-ranging collection of essays is a meditation on society’s complicated relationship with viruses. In pondering SARS-CoV-2, HIV and more, Osmundson calls for more equitable access to medical care (SN: 7/16/22 & 7/30/22, p. 36).

The Milky Way
Moiya McTier
Grand Central Publishing
$27

This absorbing “autobiography,” written from the perspective of the Milky Way (a very sassy Milky Way), draws on mythology and astronomy to persuade readers that our home galaxy deserves respect and admiration (SN: 9/10/22, p. 28). 

A Portrait of the Scientist as a Young Woman
Lindy Elkins-Tanton
William Morrow
$29.99

In this moving memoir, Elkins-Tanton recounts her journey to becoming a planetary scientist and leader of a NASA asteroid mission. Her struggles with childhood trauma and sexism in her career lay bare the barriers that many women in science still face (SN: 8/13/22, p. 26).

An Immense World
Ed Yong
Random House
$30

So much of the world is beyond the grasp of human perception, but this safari through animal senses helps readers imagine what we’re missing (SN: 7/16/22 & 7/30/22, p. 36).

How Far the Light Reaches
Sabrina Imbler
Little, Brown, & Co.
$27

By drawing parallels between their own life and the stories of bobbit worms, octopuses, sperm whales and other deep-sea dwellers, Imbler muses on such weighty themes as adaptation, survival and sexuality.  

The Last Days of the Dinosaurs
Riley Black
St. Martin’s Press
$28.99

The basic story of the downfall of nonbird dinosaurs is familiar: They were killed off by an asteroid that slammed into Earth 66 million years ago. Using the most up-to-date science, Black fleshes out this tale, painting a vivid portrait of life before and after this apocalypse (SN: 4/23/22, p. 28).  

The Rise and Reign of the Mammals
Steve Brusatte
Mariner Books
$29.99

The perfect follow-up to Black’s book on how the Age of Dinosaurs ended is this sweeping history of how the Age of Mammals began. Brusatte traces the origins of the evolutionary innovations that have made mammals so successful (SN: 6/18/22, p. 28). 

Origin
Jennifer Raff
Twelve
$30

Exactly how and when humans first came to the Americas is still unsettled science. But Raff gathers archaeological and genetic evidence to piece together a convincing scenario. She also points out past mistreatment of Indigenous communities by geneticists and calls on researchers to do better and foster more collaborations (SN: 2/12/22, p. 29). 

Pests
Bethany Brookshire
Ecco
$28.99

So-called pests are a human invention, argues Brookshire, a former staff writer for Science News for Students (now Science News Explores). In coming face to face with rats, feral cats, pythons and even elephants, Brookshire teases out the various social factors that cause people to deem certain animals a nuisance (SN: 12/3/22, p. 26). 

Buy these books from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article.

A parasite might be driving some wolves to lead or go solo.

Wolves in Yellowstone National Park infected with Toxoplasma gondii make more daring decisions than their uninfected counterparts, researchers report November 24 in Communications Biology. The wolves’ enhanced risk-taking means they are more likely to leave their pack, or become leaders of their own.

“Those are two decisions that can really benefit wolves, or could cause wolves to die,” says Connor Meyer, a field biologist at the University of Montana in Missoula. The findings reveal a parasite’s potent ability to influence a wolf’s social fate.

Disease is often considered important for wildlife, mostly in the context of killing its host, Meyer says. “We have evidence now that just being infected with a certain parasite — Toxoplasma — can have pretty major implications for wolf behavior.”

Single-celled T. gondii has a track record of altering animal behavior. Its most important hosts are cats, which provide a breeding ground for the parasite in their small intestine. The parasite offspring hitch a ride on feline feces. Other animals then ingest the parasite, which then manipulates its new hosts’ behavior by tweaking certain hormones, making the hosts bolder or more aggressive. Infected mice, for example, can fatally lose their fear of cats, allowing the parasite to infect more hosts once the mice are consumed (SN: 1/14/20). 

In Yellowstone National Park, many wolves are also infected with T. gondii, recent research has shown. So Meyer and colleagues wondered if gray wolves (Canis lupus) in the park showed any parasite mind-bending of their own.

Wolves were reintroduced to Yellowstone in 1995. Ongoing study of the park’s packs meant that the researchers had access to about 26 years’ worth of blood samples, behavioral observations and movement data for 229 of the park’s wolves.

The team screened the wolf blood for antibodies against T. gondii parasites, which reveal an infection. The researchers also noted which wolves left their pack — usually a family unit consisting of a breeding pair and their offspring — or became a pack leader. 

Both are high-stakes moves for a wolf, Meyer says. 

Infected wolves were 11 times as likely as noninfected wolves to disperse from their pack, the team found, and about 46 times as likely to eventually become leaders. The findings fit in with T. gondii’s apparent ability to boost boldness across a wide range of warm-blooded life. 

The study fills a crucial gap in the Toxoplasma pool of knowledge, says Ajai Vyas, a neurobiologist at Nanyang Technological University in Singapore, who was not involved with the study.

“Most of the earlier work has been done in the lab,” Vyas says. But there are limitations to that approach, especially for re-creating how animals experience the effects of the parasite in their natural environment. Such research has “become almost like studying whale swimming behavior in backyard pools; [it] does not work very well.”

Wolves’ enhanced boldness may even form a feedback loop, the team proposes. The researchers found that not only do cougars (Puma concolor) in the park carry the parasite, but wolves’ infection rates were highest when the animals’ ranges overlapped with the park’s densest aggregations of cougars. Infected wolf leaders may be more likely to bring pack members into riskier situations, including approaching cougar territories, making additional infections more likely. 

The feedback-loop idea is “very fascinating,” but more research is needed to confirm it, says Greg Milne, an epidemiologist at the Royal Veterinary College in London, who was not involved with the study. Such research may involve determining if infected wolves are more likely to migrate into an area with more cougars. 

“I think people are just starting to really appreciate that personality differences in animals are a major consideration in behavior,” says study coauthor Kira Cassidy, a wildlife biologist at the Yellowstone Wolf Project in Bozeman, Mont. “Now we add a parasite-impacting behavior to the list.”

Next, the team is interested in examining the long-term consequences of a T. gondii infection, and whether infected wolves make better leaders or dispersers than uninfected wolves.

 It’s also not known how infection impacts survival and reproduction rates, Cassidy says. “Infection may very well be detrimental in some ways and advantageous in others.”

Pests
Bethany Brookshire
Ecco, $28.99

We spend so much time making sure wildlife stays away from us, whether that’s setting traps, building fences or putting out poisons. Sure, unwanted guests are annoying. But why do we consider some animals “pests”? It’s all about perspective, says science journalist Bethany Brookshire. “We can put poison out for rats and protest their use as laboratory animals. We can shoot deer in the fall and show their adorable offspring to our children in the spring,” she writes in her new book, Pests: How Humans Create Animal Villains.

Brookshire argues that we deem animals “pests” when we fear them (like snakes). Or when they thrive in a niche we unintentionally created for them (think rats in the New York subway). Or when they find a way to live in a habitat now dominated by humans (all those deer in the suburbs). Sometimes we demonize an animal if we feel like it’s threatening our ability to control the landscape (like coyotes that attack our livestock, pets and even children).

Through the lens of science, history, culture, religion, personal anecdotes and a big dose of humor, Brookshire breaks down how our perspective shapes our relationships with our animal neighbors. She also goes into the field — trailing rats, hunting pythons, taming feral cats, tracking drugged-up bears — to see firsthand how pests are treated.

Science News spoke with Brookshire, a former staff writer for Science News for Students (now Science News Explores), about what we can learn from pests and how we can co­exist with them. The following conversation has been edited for clarity and brevity.

SN: What inspired you to write this book?

Brookshire: I wrote a news story that was about mice living with humans (SN: 4/19/17). [It was based on a study] showing that we’ve had house mice since we’ve had houses. I love the fact that humans have had these other animals taking advantage of the ecosystems that we create basically since we started living settled life. Every location that has humans has their “rat.” Sometimes that’s a rat, and sometimes it’s a pigeon or a cockatoo or a lizard or a horse. It’s not about what these animals are doing. Animals live in ecosystems that we create, and we hate animals that live too close.

SN: What surprised you during your research?

Brookshire: The reflexiveness of people’s responses [to pests]. People respond emotionally. When you make them pause and think about it, they go, “Oh wow, that doesn’t make any sense. I should not be caught trying to kill a raccoon with a sword.” But in the moment, you’re so wrapped up in the violation of what you see as your personal space.

The other thing is the extent to which our disdain of pests is wrapped up in social justice. A lot of times we see this hatred and disgust for animals that we see as “low class.” High-class people don’t have rats. And that’s really about social justice, about infrastructure and the ability of people to live in clean houses, store their food properly or even have a house at all.

Also, the way we deal with these animals often has vestiges of colonialism, as in the chapter on elephants. [In Kenya, European colonists] made people grow corn and sugarcane, which elephants love. Colonization created national park systems that assumed that humans had no place in wilderness, shoving out Indigenous pastoralists. Colonization created the market for poached ivory. And colonizing people assumed that Indigenous people did not like elephants or know their benefits. We are living with the consequences. Many modern efforts at elephant protection are spearheaded by Western people, and they assume the biggest issue with elephants is poaching and that Indigenous people don’t know what’s best for themselves or the elephants. In fact, human-elephant conflict [which includes elephant crop raids] is the far bigger problem, and Indigenous people have a long history of coexisting with elephants.

SN: In the book, you looked at many different cultures and included Indigenous voices.

Brookshire: It’s important to realize there’s more than one way to look at the world. By learning from other cultures, it helps us understand our biases. It’s only when you get outside of your own beliefs that you realize that’s not just the way things are.

SN: That shows up when you write about the Karni Mata Temple in India, also known as the Temple of Rats. Temple rats are not treated as pests, but a rat in a house would be.

Brookshire: That’s the result of context. And you see that in Western cultures all the time. People love squirrels. Well, they’re basically rats with better PR. Then you have people who have pet rats, who would probably scream if a sewer rat ran by.

SN: Are there any animals that you consider a pest?

Brookshire: No. The animal that I’ve probably come away with the most negative impression of is humans. It’s funny because we think we can extinct anything. And I love how these animals have gone: “Oh, poison? That’s cute.” “Oh, a trap? You’re funny.” We’ve tried to use electric fences on elephants [to stop them from eating crops]. And elephants are like, “Guess what? Ivory doesn’t conduct electricity.” Even if they don’t have tusks, elephants just pick up a log [to destroy the fence].

SN: Are you hoping to change people’s minds about pests?

Brookshire: I hope that they will ask why they respond to pests the way they do. Instead of just going, “This animal bothers me,” ask why, and does it make sense. I also hope it opens more curiosity about the animals around us. I learned from Indigenous groups just how much knowledge they have of the animals in their ecosystem. I hope more people learn. A world that you know a lot about is just a better world to live in.

Buy Pests from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article.

In the battle against the invasive house mouse on islands, scientists are using the rodent’s own genes against it.

With the right tweaks, introducing a few hundred genetically altered mice could drive an island’s invasive mouse population to extinction in about 25 years, researchers report in the Nov. 15 Proceedings of the National Academy of Sciences. The trick is adding the changes to a section of mouse DNA that gets inherited far more often than it should.

Scientists have been creating similar extra-inheritable genes — called gene drives — in the lab. The chunks are designed to get passed on to most or all of an animal’s offspring instead of the usual half, and make those offspring infertile in the bargain. Scientists have used gene drives to reduce populations of mosquitoes and fruit flies (SN: 12/17/18).

But mammals are a different story. Scientists have previously synthesized a gene drive that gets passed on in mice about 80 percent of the time (SN: 1/23/19). But the drive isn’t strong enough to stop a population quickly.

Luckily, nature has it handled. A haplotype is a naturally occurring group of genes that gets passed on as a unit during replication. The genome of the house mouse (Mus musculus) has a particular haplotype, called the t haplotype, that gets passed on to offspring more than 95 percent of the time, instead of the typical 50 percent.

This natural gene drive has benefits, says Anna Lindholm, a biologist at the University of Zurich who was not involved in the study. It “evolved naturally and continues to be present in the wild, and we have as yet not found resistance to it in wild populations,” she says. It’s also not found in species besides M. musculus, meaning it probably won’t spread to other noninvasive mice.

Molecular biologist Paul Thomas and his colleagues decided to target the t haplotype with the cut-and-paste molecular tool called CRISPR/Cas9 (SN: 8/24/16). They used CRISPR to insert the gene sequence for the CRISPR tool itself into the t haplotype. When a male mouse carrying the altered t haplotype mates with a female, the inserted genes for the CRISPR tool spring into action. It uses a special genetic guide to target and inactivate the gene for the hormone prolactin — rendering any baby female mice infertile.

The best part is that the natural t haplotype can also sterilize males, says Thomas, of the University of Adelaide in Australia. Males with two copies — homozygous males — won’t reproduce at all.

“If you could get a t to spread through a population, you could get homozygous males being sterile,” he says. “And with the addition of the CRISPR element on top of that, we get homozygous females that are also sterile.”

To find out how well the t haplotype mice do on an island where mice are wreaking havoc on biodiversity, the scientists used a computer simulation of an island with 200,000 mice. The team found that adding just 256 mice with the CRISPR-altered t haplotype could successfully drive the mouse population to zero in around 25 years. Even without CRISPR, adding mice with the normal t haplotype could tank the population in about 43 years.

But models aren’t mice. In a final test, Thomas and his colleagues made the model reality. The team altered the t haplotype in a small group of mice in the lab and used genetic tests to show that those mice would pass on their new genetics 95 percent of the time.

“This is a clever idea, to build on the t haplotype natural drive system and use CRISPR, not for spreading the construct, but for damaging genes necessary for female fertility,” Lindholm says. “This is a big advance in the development of new tools to control invasive mouse populations.”

The next step, Thomas says, will be to test the effects in real populations of mice in secure enclosures, to find out if the genetically tweaked t can stop mice from reproducing. The scientists also want to ensure that any engineered mice released into the wild have some safety mechanism in place, so other mice elsewhere remain unaffected.

The final version might target tiny mutations that only occur on one island where the pest population is isolated, Thomas suggests. If the mouse escaped onto the mainland, its altered genes would have no effect on the local mice. The scientists also want to consult with people living in the area, as officials did when genetically modified mosquitoes were released in Florida (SN: 5/14/21).

Finally, he notes, 25 years is a long wait for some endangered island populations. “We would love to see CRISPR work faster,” he says. “It’s still a work in progress.”

An ancient hominid dubbed Homo naledi may have lit controlled fires in the pitch-dark chambers of an underground cave system, new discoveries hint.

Researchers have found remnants of small fireplaces and sooty wall and ceiling smudges in passages and chambers throughout South Africa’s Rising Star cave complex, paleoanthropologist Lee Berger announced in a December 1 lecture hosted by the Carnegie Institution of Science in Washington, D.C.

“Signs of fire use are everywhere in this cave system,” said Berger, of the University of the Witwatersrand, Johannesburg.

H. naledi presumably lit the blazes in the caves since remains of no other hominids have turned up there, the team says. But the researchers have yet to date the age of the fire remains. And researchers outside Berger’s group have yet to evaluate the new finds.

H. naledi fossils date to between 335,000 and 236,000 years ago (SN: 5/9/17), around the time Homo sapiens originated (SN: 6/7/17). Many researchers suspect that regular use of fire by hominids for light, warmth and cooking began roughly 400,000 years ago (SN: 4/2/12).

Such behavior has not been attributed to H. naledi before, largely because of its small brain. But it’s now clear that a brain roughly one-third the size of human brains today still enabled H. naledi to achieve control of fire, Berger contends.

Last August, Berger climbed down a narrow shaft and examined two underground chambers where H. naledi fossils had been found. He noticed stalactites and thin rock sheets that had partly grown over older ceiling surfaces. Those surfaces displayed blackened, burned areas and were also dotted by what appeared to be soot particles, Berger said.

Meanwhile, expedition codirector and Wits paleoanthropologist Keneiloe Molopyane led excavations of a nearby cave chamber. There, the researchers uncovered two small fireplaces containing charred bits of wood, and burned bones of antelopes and other animals. Remains of a fireplace and nearby burned animal bones were then discovered in a more remote cave chamber where H. naledi fossils have been found.

Still, the main challenge for investigators will be to date the burned wood and bones and other fire remains from the Rising Star chambers and demonstrate that the fireplaces there come from the same sediment layers as H. naledi fossils, says paleoanthropologist W. Andrew Barr of George Washington University in Washington, D.C., who wasn’t involved in the work.

“That’s an absolutely critical first step before it will be possible to speculate about who may have made fires for what reason,” Barr says.

The infant universe transforms from a featureless landscape to an intricate web in a new supercomputer simulation of the cosmos’s formative years.

An animation from the simulation shows our universe changing from a smooth, cold gas cloud to the lumpy scattering of galaxies and stars that we see today. It’s the most complete, detailed and accurate reproduction of the universe’s evolution yet produced, researchers report in the November Monthly Notices of the Royal Astronomical Society.

This virtual glimpse into the cosmos’s past is the result of CoDaIII, the third iteration of the Cosmic Dawn Project, which traces the history of the universe, beginning with the “cosmic dark ages” about 10 million years after the Big Bang. At that point, hot gas produced at the very beginning of time, about 13.8 billion years ago, had cooled to a featureless cloud devoid of light, says astronomer Paul Shapiro of the University of Texas at Austin.

Roughly 100 million years later, tiny ripples in the gas left over from the Big Bang caused the gases to clump together (SN: 2/19/15). This led to long, threadlike strands that formed a web of matter where galaxies and stars were born. 

 As radiation from the early galaxies illuminated the universe, it ripped electrons from atoms in the once-cold gas clouds during a period called the epoch of reionization, which continued until about 700 million years after the Big Bang (SN: 2/6/17).

CoDaIII is the first simulation to fully account for the complicated interaction between radiation and the flow of matter in the universe, Shapiro says. It spans the time from the cosmic dark ages and through the next several billion years as the distribution of matter in the modern universe formed.

The animation from the simulation, Shapiro says, graphically shows how the structure of the early universe is “imprinted on the galaxies today, which remember their youth, or their birth or their ancestors from the epoch of reionization.”

Tyrannosaurus rex isn’t just a king to paleontologists — the dinosaur increasingly reigns over the world of art auctions. A nearly complete skeleton known as Stan the T. rex smashed records in October 2020 when a bidding war drove its price to $31.8 million, the highest ever paid for any fossil. Before that, Sue the T. rex held the top spot; it went for $8.3 million in 1997.

That kind of publicity — and cachet — means that T. rex’s value is sky-high, and the dinosaur continues to have its teeth firmly sunk into the auction world in 2022. In December, Maximus, a T. rex skull, will be the centerpiece of a Sotheby’s auction in New York City. It’s expected to sell for about $15 million.

Another T. rex fossil named Shen was anticipated to sell for between $15 million and $25 million at a Christie’s auction in Hong Kong in late November. However, the auction house pulled it over concerns about the number of replica bones used in the fossil.

“These are astronomical sums of money, really surprising sums of money,” says Donna Yates, a criminologist at Maastricht University in the Netherlands who studies high-value collectibles.

Stan’s final price “was completely unexpected,” Yates says. The fossil was originally appraised at about $6 million — still a very large sum, though nothing like the final tally, which was the result of a three-way bidding war.

But the staggering amounts of money T. rex fossils now fetch at auction can mean a big loss for science. At those prices, the public institutions that might try to claim these glimpses into the deep past are unable to compete with deep-pocketed private buyers, researchers say.

One reason for the sky-high prices may be that T. rex fossils are increasingly being treated more like rare works of art than bits of scientific evidence, Yates says. The bones might once have been bought and sold at dusty “cowboy fossil” dealerships. But nowadays these fossils are on display in shiny gallery spaces and are being appraised and marketed as rare objets d’art. That’s appealing to collectors, she adds: “If you’re a high-value buyer, you’re a person who wants the finest things.”

But fossils’ true value is the information they hold, says Thomas Carr, a paleontologist at Carthage College in Kenosha, Wis. “They are our only means of understanding the biology and evolution of extinct animals.”

Keeping fossils of T. rex and other dinosaurs and animals in public repositories, such as museums, ensures that scientists have consistent access to study the objects, including being able to replicate or reevaluate previous findings. But a fossil sold into private or commercial hands is subject to the whim of its owner — which means anything could happen to it at any time, Carr says.

“It doesn’t matter if [a T. rex fossil] is bought by some oligarch in Russia who says scientists can come and study it,” he says. “You might as well take a sledgehammer to it and destroy it.”

A desire for one’s own T. rex

There are only about 120 known specimens of T. rex in the world. At least half of them are owned privately and aren’t available to the public. That loss is “wreaking havoc on our dataset. If we don’t have a good sample size, we can’t claim to know anything about [T. rex],” Carr says.

For example, to be able to tell all the ways that T. rex males differed from females, researchers need between 70 and 100 good specimens for statistically significant analyses, an amount scientists don’t currently have.

Similarly, scientists know little about how T. rex grew, and studying fossils of youngsters could help (SN: 1/6/20). But only a handful of juvenile T. rex specimens are publicly available to researchers. That number would double if private specimens were included.

Museums and academic institutions typically don’t have the kind of money it takes to compete with private bidders in auctions or any such competitive sales. That’s why, in the month before Stan went up for auction in 2020, the Society for Vertebrate Paleontology, or SVP, wrote a letter to Christie’s asking the auction house to consider restricting bidding to public institutions. The hope was that this would give scientists a fighting chance to obtain the specimens.

But the request was ignored — and unfortunately may have only increased publicity for the sale, says Stuart Sumida, a paleontologist at California State University in San Bernardino and SVP’s current vice president. That’s why SVP didn’t issue a public statement this time ahead of the auctions for Shen and Maximus, Sumida says, though the organization continues to strongly condemn fossil sales — whether of large, dramatic specimens or less well-known creatures. “All fossils are data. Our position is that selling fossils is not scientific and it damages science.”

Sumida is particularly appalled at statements made by auction houses that suggest the skeletons “have already been studied,” an attempt to reassure researchers that the data contained in that fossil won’t be lost, regardless of who purchases it. That’s deeply misleading, he says, because of the need for reproducibility, as well as the always-improving development of new analysis techniques. “When they make public statements like that, they are undermining not only paleontology, but the scientific process as well.”

And the high prices earned by Stan and Sue are helping to drive the market skyward, not only for other T. rex fossils but also for less famous species. “It creates this ripple effect that is incredibly damaging to science in general,” Sumida says. Sotheby’s, for example, auctioned off a Gorgosaurus, a T. rex relative, in July for $6.1 million. In May, a Deinonychus antirrhopus — the inspiration for Jurassic Park’s velociraptor — was sold by Christie’s for $12.4 million.

Protecting T. rex from collectors

Compounding the problem is the fact that the United States has no protections in place for fossils unearthed from the backyards or dusty fields of private landowners. The U.S. is home to just about every T. rex skeleton ever found. Stan, Sue and Maximus hail from the Black Hills of South Dakota. Shen was found in Montana.

As of 2009, U.S. law prohibits collecting scientifically valuable fossils, particularly fossils of vertebrate species like T. rex, from public lands without permits. But fossils found on private lands are still considered the landowner’s personal property. And landowners can grant digging access to whomever they wish.

Before the discovery of Sue the T. rex (SN: 9/6/14), private owners often gave scientific institutions free access to hunt for fossils on their land, says Bridget Roddy, currently a researcher at the legal news company Bloomberg Law in Washington, D.C. But in the wake of Sue’s sale in 1997, researchers began to have to compete for digging access with commercial fossil hunters.

These hunters can afford to pay landowners large sums for the right to dig, or even a share of the profits from fossil sales. And many of these commercial dealers sell their finds at auction houses, where the fossils can earn far more than most museums are able to pay.

Lack of federal protections for paleontological resources found on private land — combined with the large available supply of fossils — is a situation unique to the United States, Roddy says. Fossil-rich countries such as China, Canada, Italy and France consider any such finds to be under government protection, part of a national legacy.

In the United States, seizing such materials from private landowners — under an eminent domain argument — would require the government to pay “just compensation” to the landowners. But using eminent domain to generally protect such fossils wouldn’t be financially sustainable for the government, Roddy says, not least because most fossils dug up aren’t of great scientific value anyway.

There may be other, more grassroots ways to at least better regulate fossil sales, she says. While still a law student at DePaul University in Chicago, Roddy outlined some of those ideas in an article published in Texas A&M Journal of Property Law in May.

One option, she suggests, is for states to create a selective sales tax attached to fossil purchases, specifically for buyers who intend to keep their purchases in private collections that are not readily available to the public. It’s “similar to if you want to buy a pack of cigarettes, which is meant to offset the harm that buying cigarettes does to society in general,” Roddy says. That strategy could be particularly effective in states with large auction houses, like New York.

Another possibility is to model any new, expanded fossil preservation laws on existing U.S. antiquities laws, intended to preserve cultural heritage. After all, Roddy says, fossils aren’t just bones, but they’re also part of the human story. “Fossils have influenced our folklore; they’re a unifier of humanity and culture rather than a separate thing.”

Though fossils from private lands aren’t protected, many states do impose restrictions on searches for archaeological and cultural artifacts, by requiring those looking for antiquities to restore excavated land or by fining the excavation of certain antiquities without state permission. Expanding those restrictions to fossil hunting, perhaps by requiring state approval through permits, could also give states the opportunity to purchase any significant finds before they’re lost to private buyers.

Preserving fossils for science and the public

Such protections could be a huge boon to paleontologists, who may not even know what’s being lost. “The problem is, we’ll never know” all the fossils that are being sold, Sumida says. “They’re shutting scientists out of the conversation.”

And when it comes to dinosaurs, “so many of the species we know about are represented by a single fossil,” says Stephen Brusatte, a paleontologist at the University of Edinburgh. “If that fossil was never found, or disappeared into the vault of a collector, then we wouldn’t know about that dinosaur.”

Or, he says, sometimes a particularly complete or beautifully preserved dinosaur skeleton is found, and without it, “we wouldn’t be able to study what that dinosaur looked like, how it moved, what it ate, how it sensed its world, how it grew.”

The point isn’t to put restrictions on collecting fossils so much as making sure they remain in public view, Brusatte adds. “There’s nothing as magical as finding your own fossils, being the first person ever to see something that lived millions of years ago.” But, he says, unique and scientifically invaluable fossils such as dinosaur skeletons should be placed in museums “where they can be conserved and studied and inspire the public, rather than in the basements or yachts of the oligarch class.”

After its record-breaking sale, Stan vanished for a year and a half, its new owners a mystery. Then in March 2022, news surfaced that the fossil had been bought by the United Arab Emirates, which stated it intends to place Stan in a new natural history museum.

Sue, too, is on public view. The fossil is housed at Chicago’s Field Museum of Natural History, thanks to the pooled financial resources of the Walt Disney Corporation, the McDonald Corporation, the California State University System and others. That’s the kind of money it took to get the highest bid on a T. rex 25 years ago.

And those prices only seem to be going up. Researchers got lucky with Sue, and possibly Stan.

As for Shen, the fossil’s fate remains in limbo: It was pulled from auction not due to outcry from paleontologists, but over concerns about intellectual property rights. The fossil, at 54 percent complete, may have been supplemented with a polyurethane cast of bones from Stan, according to representatives of the Black Hills Institute of Geological Research in Hill City, S.D. That organization, which discovered Stan, retains a copyright over the skeleton.

In response to those concerns, Christie’s pulled the lot, and now says that it intends to loan the fossil to a museum. But this move doesn’t reassure paleontologists. “A lot of people are pleased that the sale didn’t go through,” Sumida says. “But it sort of just kicks the can down the road.… It doesn’t mean they’re not going to try and sell it in another form, somewhere down the road.”

Ultimately, scientists simply can’t count on every important fossil finding its way to the public, Carr says. “Those fossils belong in a museum; it’s right out of Indiana Jones,” he says. “It’s not like they’re made in a factory somewhere. Fossils are nonrenewable resources. Once Shen is gone, it’s gone.”

A dinosaur unearthed in Mongolia is making a splash among paleontologists, as its sleek physique adds potential evidence to the idea that some dinos were suited for life in the water.  

Natovenator polydontus may be the first known nonbird dinosaur to have possessed a streamlined body comparable to that of modern diving birds, researchers report December 1 in Communications Biology. Natovenator and other closely related dinosaurs may have been swimming predators, the researchers say, challenging the popular notion that all dinos were landlubbers.

Natovenator was small like a duck and probably used its forelimbs when swimming, says Yuong-Nam Lee, a vertebrate paleontologist at Seoul National University in South Korea. “We think that Natovenator lived in shallow water and ate small fish,” he says.

This isn’t the first time that researchers have suspected a nonbird dinosaur of having an aquatic lifestyle. For years, paleontologists have debated whether spinosaurs were aquatic predators (SN: 3/23/22). And in 2017, researchers reported that Halszkaraptor —a close relative of Natovenator — had features analogous to those of aquatic birds and reptiles, though the scientists were unable to infer a body shape.   

In the new study, Lee and colleagues analyzed a well-preserved skeleton from the Hermiin Tsav fossil formation in Mongolia, found in rocks from the Upper Cretaceous, which dates to about 100 million to 66 million years ago. The skull, teeth, neck and limbs of Natovenator are akin to those of Halszkaraptor, the team reports, suggesting the two probably had comparable lives.

What’s more, the orientation of Natovenator’s ribs indicates that it had a streamlined body like that of modern waterfowl, with a compressed and flattened rib cage akin to aquatic reptiles, the researchers say.

The close resemblance between Natovenator and a duck or cormorant is almost certainly an example of what’s known as convergent evolution, says Thomas Holtz Jr., a vertebrate paleontologist at the University of Maryland in College Park, who was not involved in the study. “Similar body plans evolve because of similar lifestyles.”

It remains unclear just how strong a swimmer Natovenator may have been. The dinosaur’s forelimbs appear short, and its hind limbs seem to lack attributes of kick-propelled swimmers like loons, Holtz says. But semiaquatic mammals like minks and some other successful modern swimming predators have skeletons that aren’t highly specialized for life in the water either, he says. “So Natovenator might be intermediate in swimming ability, between something like a mink and a loon.”

When astronaut Eugene Cernan stepped from the moon’s surface into his spacecraft in December 1972, he was aware it was the end of an era. His mission, Apollo 17, was the last of the Apollos.

“Take your final look at the valley of Taurus-­Littrow, except from orbit,” Cernan said of the view before the craft lifted off. “We’re on our way, Houston!”

And with that, the last person to walk on the moon returned to Earth. No other boots have touched lunar soil in the 50 years since then.

Now, NASA is preparing to go back, and China is on its way too. On November 16, the U.S. Artemis I mission launched to bring the first crew-ready space capsule to the vicinity of the moon since Cernan and his two crewmates left half a century ago.

That spacecraft isn’t carrying any astronauts; the mission was designed to check technology and other systems that will eventually take people to the moon, on Artemis III, no sooner than 2025. This time, NASA says, the intention is to stay longer, to learn how to live on the moon and eventually send people to Mars.

The obvious next question is, who gets to go?

Thanks to social, political and scientific changes over the last 50 years, today’s astronauts are not like the astronauts of the past. They are more diverse in sex, race and field of expertise. The next set of people to walk on the moon will face different challenges and require different skills, temperaments and support systems than the Apollo crews.

And some groups are thinking about how to include people with disabilities in the spacefaring future. Preparing for a more permanent human presence in space will require rethinking the right stuff. Future lunar crews may reflect our lives on Earth more faithfully, making space for everyone.

Becoming an astronaut

NASA has declared that upcoming missions to the moon will include a woman and a person of color, setting two firsts for lunar astronauts.

The next visitors to the moon haven’t been selected yet. But there are only about 50 people to choose from. The 43 active astronauts and 10 astronaut candidates, who are still in training, come from a variety of backgrounds. The list includes medical doctors, military pilots, geologists, microbiologists, engineers and others. Of NASA’s active astronauts, about 37 percent are women.

“The astronaut corps is, of course, NASA’s most visible workforce,” says Lori Garver, who was NASA’s deputy administrator from 2009 to 2013. “Because of that, NASA has, I think, a responsibility to have an astronaut corps that reflects the nation.”

Modern astronauts are already different from those of Apollo. For its first class of astronauts in 1959, NASA recruited military fighter pilots shorter than 5 feet, 11 inches (because of the tight space in the Mercury space capsule). At the time, all military test pilots were white men, so all astronauts were too.

NASA recruited its first class of “scientist-­astronauts” in 1964. The move drew criticism from pilots. In an interview, Cernan — who shared his spot on Apollo 17 with the only geologist to walk on the moon, Harrison Schmitt — called science “a parasite” on the moon program. “Science is not the reason we learned to fly,” he griped. Cernan later referred to Schmitt as “Dr. Rock” and worried that he wouldn’t be able to get out of a tough spot on his own.

But according to NASA’s mission report, Apollo 17 was “the most productive and trouble-free manned mission.” It “demonstrated the practicality of training scientists to become qualified astronauts.”

Today, 42 percent of NASA’s active astronauts have a research science or medicine background, in fields ranging from oceanography to physics.

Counterintuitively, though, NASA’s definition of “astronaut” doesn’t require going to space. Once you’ve made it through the strenuous and selective application and training process, you’re a member of the astronaut corps, whether you leave Earth or not.

The first step in applying to be an astronaut is “unnervingly underwhelming,” says geobiologist Zena Cardman, who joined the astronaut corps in 2017 but has not yet been to space. “You submit a very short resume to USAJobs.gov, and then you wait for a long time,” she says. (Full disclosure: I applied to the astronaut program myself in 2012. I kept the rejection postcard for years.)

The minimum requirements for applying are being a U.S. citizen, having a master’s degree in engineering, biological science, physical science or math, and two years of professional experience, including teaching or graduate school. Pilots can substitute the two years of experience with 1,000 hours of jet-flying experience. Candidates who make it through that first round travel to Houston for a two-round interview process.

“What we’re looking for in these first few Artemis missions … first and foremost, is technical expertise,” astronaut Reid Wiseman, chief of NASA’s Astronaut Office, said in a news briefing on August 5. A lot of those desired skills revolve around acquiring resources to support long stays.

Artemis III plans to send people to the lunar south pole, which could be a reasonable place to put a long-term base. It has regions that will be in sunlight for the entire 6.5-day mission. The light will help generate energy from solar power. And it has regions in permanent shadow that host pockets of water ice, which could be used for water and fuel for human settlements.

The possibility of finding and using resources on the moon is part of why science backgrounds, especially in geology, are now more important for astronauts. But in the astronaut corps, everyone does everything, Cardman says. Her background is in geology and microbiology. She’s done fieldwork in Antarctica, the Arctic, underground caves and on ocean research vessels. Space “seemed like the ultimate fieldwork endeavor,” she says.

To round out her skills, she’s getting trained in engineering and aviation, and her test pilot colleagues are learning geoscience. “We will have roles, but we won’t be siloed,” she says.

Science expertise

A science background is considered a necessity for today’s 43 active astronauts (top). Many are in the military, but also have degrees in medicine, geoscience or physics. The original Apollo astronauts (bottom) were mostly military pilots, some with engineering backgrounds.

Beyond technical skill, the next most important characteristic NASA looks for is: “Are you a team player?” Wiseman says. Working together was important on the Apollo missions. But those missions lasted 12 days at most, with three days tops on the lunar surface. Astronauts on a weeks-long Artemis mission to the moon or a years-long mission to Mars will need to survive in stressful, challenging, isolated environments (SN: 11/29/14, p. 22). Getting along becomes crucial to staying alive.

That explains why the interview process includes teamwork exercises and group dynamic activities to simulate the kinds of situations astronauts would find themselves in, Cardman says.

The interview also involves medical screening. The details are not public, but “they really go quite in depth,” Cardman says. There’s no official requirement for any particular body type or standards for physical fitness, like running a mile in a certain time or doing a certain number of pull-ups. “It’s more functional,” she says. As long as you can meet the mental and physical demands of a spacewalk, it doesn’t matter how you get in shape. Cardman’s exercise of choice is powerlifting.

Ultimately, there are thousands more applicants than there are openings for astronaut jobs. “The final selection is somewhat subjective,” Garver says. “So I think it’s absolutely appropriate that you look at the demographic along with the qualifications.”

Take it to the limit

There’s one other medical requirement for the next people to walk on the moon: They can’t have already spent too much time in space.

Over time, exposure to the harmful charged particles that zip around space can increase a person’s risk of developing cancer. For astronauts’ safety, NASA limits the amount of radiation an astronaut can absorb over their career. (SN: 7/4/20 & 7/18/20, p. 18).

From 1995 until 2021, those bounds were dependent on an astronaut’s age and sex. The limit was the amount of radiation that correlates with a 3 percent risk of dying from cancer caused by radiation exposure. But because women were considered to have higher risks of dying from radiation-­related cancers, that limit grounded female astronauts earlier than males.

Effectively, women were allowed about 150 millisieverts of radiation in their careers, while men were allowed closer to 800 millisieverts, says emergency medicine physician and aerospace engineer Erik Antonsen of Baylor College of Medicine in Houston.

“It was a consequence of the way we were calculating risk that women were being limited much earlier in their career and could not fly as much as men,” Antonsen says. “We had to dive deep into that stuff, come back up for air and say, hey man, there’s not justification for this stuff. And it’s causing discrimination against females.”

Antonsen notes that no openly transgender astronauts have flown, but he can’t think of any medical issues that would hold them back.

In 2021, the National Academies of Sciences, Engineering and Medicine released a report urging NASA to change the limit to 600 millisieverts of radiation over a career for everyone, regardless of sex or age. That amounts to about 400 days in orbit around the moon or 680 days on the lunar surface, some of the time in a habitat, for an astronaut with no other spaceflight exposures.

NASA, the German Aerospace Center and the Israel Space Agency are flying a pair of dummies on Artemis I to test a radiation protection vest for female astronauts, which might help reduce radiation risks further if worn on future missions.

That could all be good news for Cardman. She and her cohort, who are beginning to fly missions to the International Space Station, are likely candidates for Artemis III. Cardman herself could be the first woman on the moon.

She’s modest about it. “I would be thrilled to go to the moon, of course,” she says. “Depending on the timeline, who knows. But it’s pretty exciting to know I work with the people who will be the first ones setting foot on the moon in half a century.”

The new right stuff

Even though there are no official astronaut health standards, NASA does end up selecting “the healthiest damn people to fly,” Antonsen says.

Commercial spaceflight is expanding the pool of people who get to go to space. Companies like SpaceX, which is building the moon lander for Artemis III, and Blue Origin are already sending paying customers on space joyrides. These companies have different goals, incentives and risk tolerances than NASA does.

“The beautiful thing about this is, the goal is eventually to send just people,” Antonsen says. “It’s changing. And it should change.”

SpaceX would not comment on how it chooses who it sends to space. But Antonsen speculates that some companies’ only criteria for their customers will be “making sure they can walk up the stairs to get to the vehicle.”

And even that might not be the final barrier for long. Some organizations are investigating how disabled people can live and work in space.

“Disability inclusion affects how we design our spacecraft,” says AJ Link, communications director of the nonprofit advocacy group AstroAccess. “If we can make space accessible, we can make any space accessible.”

By organizing flights for disabled people on zero gravity aircraft, AstroAccess aims to show that disabled people have strengths that could be useful in space. In October 2021, 12 people with various disabilities took a parabolic flight, in which the plane took a repeating upward and downward trajectory to give the passengers inside a few minutes of weightlessness.

“My personal, emotional conclusion was, it was wicked fun,” says Sheri Wells-Jensen, a linguist at Bowling Green State University in Ohio. Wells-­Jensen, who is blind, was one of the people on that flight. She plans to try it again in December, on the anniversary of Apollo 17’s departure from the moon, despite describing herself as a “big chicken.”

“I’m not a thrill seeker. I don’t even like roller coasters,” she says. But in zero g, she was “surprised by how not terrified” she was.

She was also surprised at how useless her normal instincts were. In simulated lunar gravity, a tiny hop sent her flying to conk her head on the ceiling. The plane was so noisy that her normal ways of orienting by sound didn’t work. She felt like there was no up or down. “I’m damn well oriented on Earth, but boy, there were several moments there where I had nothing,” she says.

Learning how disabled people behave on spaceflights will help all astronauts in the future, regardless of disability, Wells-Jensen says.

“Space is a profoundly disabling environment. It’s always trying to kill you,” Wells-Jensen says. What happens if an astronaut loses their vision, whether temporarily or permanently, on the way to Mars? Or if the spacecraft lights go off, or smoke makes it hard to see? Designing a spacecraft to be used by blind people, she says, will help all astronauts navigate those situations.

Similarly, if an astronaut loses use of their legs, knowing how people with amputations or limb deficiencies navigate a spacecraft will give them options. “For able-bodied people who acquire a disability in space, we’re not just going to send them home,” Wells-Jensen says. “How do we make sure they’re safe and can still do their jobs?”

Wells-Jensen hopes that sending disabled people on zero-g flights will raise awareness of how capable they are as well. “A disabled person could take a suborbital flight tomorrow,” she says. “I think at this point, the limiting factor is cultural, rather than technological.”

The European Space Agency is also recruiting disabled astronauts, with physical characteristics such as limb deficiencies or short stature that would normally disqualify them. These “parastronauts” will help study the kinds of adaptations needed for disabled people to fly in space. In November, ESA named its first parastronaut: John McFall, a British paralympic sprinter and orthopedist, whose right leg was amputated after a motorcycle accident when he was 19.

Both ESA and AstroAccess argue that now is the time to consider accessibility in space, before the spacefaring vehicles of the future are finalized.

“Retrofitting is hard,” Wells-Jensen says. “Building things the way you want them is much easier.”

That could be especially important for private companies like SpaceX that are designing moon vehicles. The Federal Aviation Administration, which oversees commercial space transportation, has a legal moratorium on setting regulations about the safety of participants in private spaceflights until October 2023 to give the industry time to get established and collect data. AstroAccess, for one, wants to help guide those regulations.

“We want to fundamentally change the way humanity goes to space,” Wells-Jensen says. “We can’t become a spacefaring species if only some of us can go.”

Mauna Loa, Earth’s largest active volcano, abruptly woke up on November 27 after an almost 40-year nap. The volcano shot fountains of lava as high as 50 meters into the air, while rivers of molten rock streamed down the volcano’s flanks toward Saddle Road, the main highway on Hawaii’s Big Island.

Mauna Loa stands shoulder to shoulder with four other volcanoes, including explosively dramatic Kilauea (SN: 7/16/18) and quietly grumbling Mauna Kea (SN: 5/14/20). Kilauea has grabbed headlines in recent years with its pyrotechnics while Mauna Loa has slumbered. But the sleeping giant hasn’t been so quiet in the past, says Ingrid Johanson, a geophysicist at the U.S. Geological Survey’s Hawaiian Volcano Observatory in Hilo.

Historically, she says, Mauna Loa would awaken every seven years or so on average. This last stretch between eruptions “is quite a big gap.”

Science News talked with Johanson about how Mauna Loa tends to wake up, what’s in the path of the lava and what sort of neighbors Kilauea and Mauna Loa are.

Were there warning signs that Mauna Loa was about to erupt?

“It depends on what you mean by warning,” Johanson says. “In a manner of speaking, we’ve known that Mauna Loa was showing signs of unrest since 2015.” At that time, she says, there was an uptick in the rate of local earthquakes, as well as in GPS observations of land deformation — a bulging upward of the land surface that indicates magma is on the move below ground.

Those signs tapered off a bit and then increased again over the last six months, suggesting “that the situation was evolving,” Johanson says. But when the volcano would actually erupt wasn’t possible to determine. “Fundamentally, we had about an hour and a half of warning,” she says. That was the time span between when researchers noted a sudden swarm of earthquakes pointing to an imminent eruption and the emergence of lava.

That short notice is “true to form” for Mauna Loa, she adds. Its “other eruptions have evolved very quickly in the same way.”

How is the monitoring of Mauna Loa different than it was before the last eruption in 1984?

“One of the big differences between 1984 and now is the technology,” Johanson says.

“We can see more earthquakes [and] detect a wider range of frequencies in the seismic waves. And we have GPS and electronic tiltmeters to measure deformation continuously.” That technology allowed scientists to detect not only that there was land deformation recently, but also how it was changing over time, giving just a bit of extra warning time.

That wasn’t possible 40 years ago. Back then, researchers measured deformation by hand, hiking up to the volcano’s summit every few weeks or so. “There was a technique called EDM, for electronic distance measuring, which was essentially shining a laser into a reflector, so you could get very precise distance measurements,” Johanson says. Subtle shifts in the reflector’s location, installed on the volcano, helped reveal the deformation.

Does the current eruption pose a threat to people?

“It’s a little early to tell — it’s not yet clear how much volume we can expect out of this eruption,” Johanson says. “I don’t think it’s a given that this will be a more momentous eruption than past ones, but there is a sense of maybe coming back to business as usual for the volcano.”

The good news is that the lava flows don’t currently pose a threat to communities on the Big Island. However, Saddle Road connects the island’s eastern and western sides, Johanson notes. “If the lava were to cross the highway, it would really impact the island.”

But the eruption has interrupted data collection for one of climate science’s most iconic charts: the Keeling Curve, a nearly unbroken 60-year record of atmospheric carbon dioxide that shows a steady rise in levels of the gas.

The carbon dioxide data are collected from instruments at the Mauna Loa Observatory.  The eruption cut off power to the observatory on November 28. As of November 30, the power had not yet been restored, and lava flows had cut off access to the site. For now, it’s unclear if the interruption will have a lasting impact on data collection.

Kilauea has been erupting more or less continuously for decades. How are Kilauea and Mauna Loa connected?

They are two separate volcanoes with geochemically distinct lavas, suggesting their plumbing systems — the networks of tunnels and channels through which magma moves — are separate. That plumbing separation probably occurs below the crust and in the mantle, Johanson says, though ultimately the volcanoes tap into the same mantle hot spot (SN: 1/6/22).

That said, Kilauea and Mauna Loa are uneasy neighbors, communicating through changes in pressure and stress underground, she says. Pressure changes in the plumbing beneath one volcano can subtly affect the other, for example, altering how easy it is for one volcano to expand, making way for more magma to move in. “They do kind of elbow each other a little bit.”

Ancient DNA may be leading paleontologists astray in attempts to date when woolly mammoths and woolly rhinos went extinct.

In 2021, an analysis of plant and animal DNA from the Arctic spanning about the last 50,000 years suggested that mammoths survived in north-central Siberia as late as about 3,900 years ago (SN: 1/11/22). That’s much later than when the youngest mammoth fossil found in continental Eurasia suggests the animals died out; it dates to about 10,700 years ago. Only on Wrangel Island off the coast of Siberia and the Pribilof Islands in the Bering Sea were mammoths known to have survived later.

The finding was one of several in recent years using ancient DNA to suggest new insights into animal extinctions. Genetic evidence from woolly rhinos in Eurasia and horses in Alaska have also indicated that these animals remained thousands of years longer in some areas than was thought.

But thousands of years is also how long the animals’ large bones can linger on the ground in the frigid north, slowly weathering and shedding tiny bits of DNA, two researchers write November 30 in Nature.

That means that the youngest ancient DNA in sediment samples may have come from such bones, not living mammoths, woolly rhinos and other megafauna. Studies that rely on this genetic evidence could skew estimates of when these animals went extinct by thousands of years toward the present, say paleontologists Joshua Miller of the University of Cincinnati and Carl Simpson of the University of Colorado Boulder.

When, and why, mammoths and some other Ice Age creatures died out is a lingering mystery. Dating when these animals went extinct could help reveal what drove them to their demise — humans, a warming climate, some combination of the two or something else entirely (SN: 11/13/18; SN: 8/13/20).

But getting a good sense of when a species disappeared from its range, or from the planet, is not straightforward. For long-gone animals, fossils can help, but it would be a huge coincidence if the youngest fossil ever found of an extinct species was also the last individual to live.

Where fossils give out, DNA has started to take over. For the last two decades, environmental DNA, or eDNA, has become a go-to technique to find out what organisms are living, or used to live, in a certain place (SN: 1/18/22).

Paleontologists generally focus on a variant of eDNA that gloms onto minerals and other material and gets buried over time. That “sedimentary ancient DNA,” or sedaDNA, is what evolutionary geneticist Yucheng Wang of the University of Cambridge and his colleagues analyzed in the 2021 study on mammoths.

“The DNA can come from a living animal, but it can also come from poop, from bones,” Miller says. “In our case, we’re focusing on bones.”

In warmer climates, a bone lasts long enough to spread DNA for at most a few decades, which usually is not important for getting a general date of extinction, he says. “But up in these cold settings, you would expect a much, much larger, even millennial-scale gap.”

Miller and Simpson base their estimates of how long the bones of dead mammoths can shed DNA into the environment on radiocarbon dating of the bones of large animals found on the Earth’s surface in cold places today. Caribou antlers as old as 2000 years have been found on the islands of Svalbard in Norway and Ellesmere Island in Canada, and 5,000-year-old remains of elephant seals near the coastline of Antarctica.

Wang and his colleagues disagree that the mammoth eDNA in their sample could be partly from cold, old bones weathering down. In a reply in the same issue of Nature, they point out, for instance, that the very youngest mammoth eDNA they found shows low genetic diversity, precisely what you’d expect if the DNA actually came from a declining population at the end of the mammoth’s time on Earth, instead of from a thriving population earlier on.

“I think Miller and Simpson bring up a valid point for further testing and analysis,” says evolutionary geneticist Hendrik Poinar, a pioneer of eDNA research who wasn’t involved in the 2021 mammoth study. “But I don’t think that their analysis is nearly sufficient to combat the multiple avenues of evidence which suggest late persisting megafauna,” says Poinar, of McMaster University in Hamilton, Canada. He points out, for example, that in Wang’s study the DNA evidence tracks the plants of the time period. This suggests woolly mammoths in north-central Siberia could persist thanks to the steppe-tundra, which was their natural habitat, holding on there.

For Miller, the time span between the youngest known mammoth skeletal remains from north-central Siberia and the youngest mammoth eDNA reported by Wang and his colleagues is just too suspicious.

Olympic divers slice into a pool with a quick turn underwater that minimizes splash. But not for the reasons many athletes think it does, according to research reported November 20 at a meeting of the American Physical Society’s Division of Fluid Dynamics in Indianapolis.

“The way that divers describe it,” says fluid mechanics researcher Elizabeth Gregorio of George Washington University in Washington, D.C., “is that they want to pull the splash in with them.” The goal is a nearly splashless rip entry that Gregorio says makes a sound resembling tearing paper.

To study the move, Gregorio duplicated it with hinged models that bend in the middle, much as a diver bends at the hips. She plunged the models into water to simulate divers in action.

Angles cut into the model re-created the shape of a diver’s head and arms. The shape meant the model folded in the middle, just as the angle of a diver’s arms and head after entering the water helps the athlete bend at the hips to execute a submerged turn.

The folded model pulled air behind it to create a large, air-filled cavity under the water. It’s the same thing that happens when a diver turns underwater following a dive.

The effect, Gregorio says, “reduces the jets that would come up after you enter the water,” leading to a score-boosting rip entry. Instead of “pulling the splash in,” the air-filled cavity prevents the splash from forming in the first place.

The research isn’t all about divers’ technique. Gregorio wonders if rip entries reduce the forces divers experience on impact. If so, the studies could help with splashdowns for returning space missions. She also imagines stealthy drones that slip into water without leaving attention-grabbing splashes behind.

A get-sober pill? — Science News, November 18, 1972

Researchers at the Tucson Veterans Administration Hospital have been able to reduce intoxication time in rats by administrating harmless chemicals…. Injections of vitamin B3, and vitamin B5 with cystine, were successful… Glyceraldehyde, however, was effective when ingested and sodium acetate (still untested orally) is expected to be even more effective.

Update

Inebriation and the dreaded hangover that follows still don’t have cures — but scientists haven’t stopped searching. A compound in the seeds of Japanese raisin trees appeared to fend off drunkenness in rats and sober them up (SN: 1/4/12), but follow-up research found no effect. Remedies that have worked in rodents have not yet led to treatments for people.

In July, an antihangover supplement became available in the United Kingdom and may soon appear in U.S. stores. The Swedish company that makes this probiotic pill, Myrkle (pronounced “miracle”), claims that it can break down 70 percent of the alcohol in a person’s system in one hour. But the claim is based on a single study conducted by the company.  

For decades, chemicals that make life easier — your eggs slide out of the frying pan, stains don’t stick to your sofa, rain bounces off your jackets and boots — have been touted as game changers for our busy modern lives. “Better things for better living … through chemistry,” was the optimistic slogan coined by DuPont, the company that invented the widely used chemical coating Teflon.

But this better living has come at a cost that is getting new attention. These chemicals — dubbed forever chemicals for their ability to last in the environment — are proving to have a lasting impact on human health. A growing body of research links the group of chemicals broadly known as PFAS, short for per- and polyfluoroalkyl substances, to conditions from unhealthy blood lipid levels to pregnancy complications to cancer.

Alarm about the health impacts of these chemicals has sparked a recent flurry of action from U.S. public health and regulatory officials. Warning that PFAS pose a greater health risk than previously thought, the U.S. Environmental Protection Agency in June dramatically lowered its recommended safe levels of the chemicals in drinking water.

“The updated advisory levels are based on new science, including more than 400 recent studies which indicate that negative health effects may occur at extremely low levels, much lower than previously understood,” Radhika Fox, assistant administrator of the EPA’s Office of Water, said in June at the Third National PFAS Conference, held in Wilmington, N.C.

Soon after, the National Academies of Sciences, Engineering and Medicine released the first clinical guidelines quantifying blood concentration levels of PFAS that could put someone’s health at risk. The 300-page report urges clinicians to recommend regular blood tests for anyone exposed to high levels of the chemicals and to provide information on how to limit exposure, such as installing special filters known to reduce PFAS in drinking water.

In the United States alone, by one measure, the tally in medical care costs and lost productivity from PFAS exposure linked to five medical conditions adds up to at least $5.5 billion annually, researchers at New York University reported July 26 in Exposure and Health. Those conditions include low birth weight, childhood obesity, hypothyroidism in women, and kidney and testicular cancers.

“We only looked at two of the more than 9,000 chemicals in the PFAS family, so we’re just seeing the tip of an iceberg,” says Leonardo Trasande, a pediatrician and environmental health expert at NYU Langone Health.

PFAS are found in many products, including:

• Firefighting foam
• Paint
• Sunscreen
• Makeup
• Dental floss
• Textiles
• Guitar strings
• Artificial turf
• Microwave popcorn bags
• Fast-food packaging
• Carpeting

Ubiquitous chemicals

Among those most at risk of exposure are firefighters: PFAS make protective gear more water resistant, and the chemicals are found in a widely used fire suppressant foam. But most people have some measurable level of PFAS in their bodies, according to the U.S. Centers for Disease Control and Prevention. Exposure typically comes from ingesting PFAS-contaminated drinking water or food grown in soil treated with fertilizers made from sewage contaminated with the chemicals (SN: 11/24/18, p. 18). An estimated 2,854 locations across the United States have PFAS contamination.

“People and communities have had significant exposure to these chemicals. If they can ID that they are in an area of significant exposure, they should seek testing through their usual source of care,” says Ned Calonge, an epidemiologist at the Colorado School of Public Health in Aurora who chaired the committee that wrote the National Academies report. The committee linked PFAS exposure to a slightly different list of conditions than the NYU team, finding “sufficient evidence” linking PFAS to four conditions: poor antibody response to vaccination, abnormally high cholesterol levels, decreased infant and fetal growth, and kidney cancer. Evidence was “suggestive” for breast and testicular cancers, as well as thyroid problems and ulcerative colitis, an inflammatory bowel disease.

The report calls for more research into the health effects of PFAS, noting gaps in evidence on everything from neurological issues to bone density. These chemicals have a wide range of impacts on multiple systems in the body, Calonge says. And they’re “ubiquitous in the environment.”

Newer, not safer

PFAS have been produced in the United States since the 1940s. Because they are good at repelling oil and water, holding up at high temperatures and reducing friction, the chemicals became useful for a vast array of products, including carpeting, upholstery, food packaging and even dental floss. Yet, relatively few of the 9,000 or so versions of these synthetic chemicals have been studied for their toxicologic effects.

Many PFAS are now recognized as endocrine disruptors, chemical compounds that interfere with the normal functioning of the endocrine, or hormonal, system. But PFAS have other effects that can boost cancer risk, such as weakened immunity, excessive cell growth and altered gene activity. One study found a greater than twofold increase in kidney cancer risk between people with the highest versus lowest blood levels of one common PFAS called perfluorooctanoic acid, or PFOA, researchers reported in 2021 in the Journal of the National Cancer Institute.

A newer generation of PFAS was assumed to be safer because the chemicals are less likely to accumulate in the body. But these newer compounds are structurally similar to the older ones and can be just as harmful to health as their cousins, Trasande says. These newer molecules “are increasingly being associated with diseases like gestational diabetes. We’re just starting to see the bigger problem that might be at play.”

The EPA’s new drinking water advisory aims to tackle both old and new PFAS. It targets two of the earlier and most commonly found kinds of PFAS in the environment: PFOA and perfluorooctane sulfonic acid, or PFOS. The advisory reduces the level of drinking water contamination below which adverse health effects are not expected from 70 parts per trillion to 0.004 and 0.02 ppt, respectively. Those levels are based on routine exposure to them over a lifetime.

The EPA’s health advisory also provided the first-ever recommendations on two of the newer kinds of PFAS: hexa­fluoropropylene oxide dimer acid and HFPO ammonium salt, collectively known as GenX chemicals, and perfluorobutane sulfonic acid, or PFBS. The agency set the drinking water safety threshold at 10 ppt for GenX chemicals and 2,000 ppt for PFBS. These newer chemicals have similar persistence in the environment, the agency states.

Consumers can ask their municipal water provider for data on PFAS testing in their area. Testing is becoming more common, and providers should be able to list which PFAS they test for. Private wells can be contaminated with PFAS if they are near manufacturers that produce or use the chemicals, as well as airfields where PFAS are used for firefighting, firefighting training areas and some waste disposal sites. People with private wells near one of these facilities can get their water tested. The EPA is giving grants to help underserved small and disadvantaged communities provide household water quality testing and comply with drinking water regulations.

PFAS price tag

Because there are limited available data on the health effects of the newer generation of chemicals, the NYU and National Academies reports focused on the impacts of older PFAS.

First, the NYU team examined PFAS chemicals in blood samples obtained from roughly 5,000 adults and children who participated in the U.S. National Health and Nutrition Examination Survey. Then, based on earlier studies linking PFAS to certain diseases and models that estimate medical costs and lost worker productivity for these illnesses, the team came up with its PFAS price tag.

Childhood obesity, the largest contributor to the overall economic toll of PFAS exposure, costs about $2.7 billion a year, the team estimates, followed by hypothyroidism in women at $1.26 billion. When the researchers considered other PFAS-linked diseases beyond the top five, such as endometriosis, obesity in adults and pneumonia in children, the estimated economic burden rose to as much as $63 billion annually.

Assessing risk

The National Academies report focused in part on how to curb that toll by providing testing guidelines to clinicians to detect high levels of PFAS in the body and try to reduce exposure.

The report provides the first clinical guidelines on how to assess a person’s disease risk. A person with a PFAS blood concentration of less than 2 nanograms per milliliter doesn’t have to worry. But for patients with blood concentrations between 2 and 20 ng/mL, clinicians should screen for conditions like unhealthy levels of fat in the blood, which can lead to heart problems. Such screening is especially important for people more vulnerable to the effects of PFAS exposure, like children, pregnant people and those who are immunocompromised. For anyone who tests above 20 ng/mL, the report encourages routine screenings for some cancers, thyroid problems and ulcerative colitis.

“For almost 20 years, we’ve been able to measure PFAS in people’s blood, but there was no guidance to say what [those measurements] mean,” says National Academies report coauthor Jane Hoppin, who heads the Center for Human Health and the Environment at North Carolina State University in Raleigh. “For the first time, this actually sets some ranges, some guidance for what could be levels of concern, and what kinds of health follow-up might be appropriate.”

She hopes that the recommendations will increase testing availability and make both doctors and patients more aware of these chemicals and their health risks. The report also encourages doctors to work with their patients to figure out where they are being exposed to PFAS and how to mitigate those risks, by cutting down on PFAS-containing products and filtering water.

Activated carbon filters, found in some countertop or pitcher filters, don’t remove PFAS as completely as reverse osmosis filters, researchers at Duke University and North Carolina State reported in 2020. The National Academies report offers a link to NSF, a testing organization that offers technical details on which filters actually filter out PFAS.

Efforts like reducing PFAS in drinking water could help. While EPA’s health advisories are recommendations and not enforceable, Trasande is pleased that the agency acted quickly, particularly on newer chemicals like GenX. But he argues that in light of what we already know and are continuing to learn about the disease burden caused by these chemicals, PFAS should undergo more testing before they are approved. Better yet, they should be regulated by class instead of taking what he calls a whack-a-mole approach.

“Our environmental policy still takes a wait-and-see approach that we should wait 20 to 30 years, which is the time that people take to develop diseases due to chemical exposures,” he says.

Pet owners may have a new reason to reach for the kibble.

Dry cat and dog food tends to be better for the environment than wet food, veterinary nutritionist Vivian Pedrinelli of the University of São Paulo in Brazil and colleagues report. Their analysis of more than 900 hundred pet diets shows that nearly 90 percent of calories in wet chow comes from animal sources. That’s roughly double the share of calories from animal ingredients in dry food.

The team factored in the cost of different pet food ingredients across several environmental measures. The findings, described November 17 in Scientific Reports, suggest that wet food production uses more land and water and emits more greenhouse gases than dry food.  

Scientists already knew that meat-heavy human diets drive greenhouse gas emissions (SN: 5/5/22). But when it comes to environmental sustainability, “we shouldn’t ignore pet food,” says Peter Alexander, an economist at the University of Edinburgh who was not involved in the work.

Just how much various pet foods impact the environment isn’t clear, Alexander says. Commercial cat and canine fares aren’t typically made from prime cuts of meat. Instead, the ingredient lists often include animal byproducts — the gristle and bits people aren’t likely to eat anyway.

How to calculate the carbon cost of these leftovers is an ongoing debate, says Gregory Okin, an environmental scientist at the University of California, Los Angeles who was not involved with study.

Some argue that the byproducts in pet food are essentially free, since they come from animals already raised for human consumption. Others note that any calories require energy and therefore incur an environmental cost. Plus, animal ingredients in pet food might not be just scraps. If they contain even a small amount of human-edible meat, that could add up to a big impact.

Knowing that there’s an environmental difference between moist morsels and crunchier cuisines could be helpful for eco-conscious pet owners, Okin says. Having that info handy at the grocery store is “super important when people are making decisions,” he adds. “There are consumers who want to pay attention.”

It’s been more than two years since the first long COVID patients called attention to their condition. But researchers are still unable to answer basic questions about it, such as how vaccination impacts one’s chances of long-term symptoms or which groups of people are most at-risk, thanks to gaping holes in long COVID data.

Some data gaps originated early in the pandemic. For instance, in spring 2020, people who lacked a travel history to China or didn’t have typical flulike symptoms were unable to get a PCR test to confirm they were infected. So when some of those people later developed long COVID, their initial illness had not been logged in medical records — making it difficult for them to get care and keeping them off most researchers’ radar.

Other data gaps reveal long-standing problems in how the medical system treats complex, chronic diseases. Doctors weren’t looking out for long-term symptoms, despite warnings from experts in other postviral diseases. And some of the most common long COVID symptoms, such as a dramatic worsening of health after exertion, lack a standard code for documentation in medical charts, making them hard to track.

Filling in those gaps is becoming increasingly crucial. Studies suggest that between 10 and 30 percent of people with COVID-19 may experience long-term symptoms, ranging from a simple loss of smell and taste to debilitating cognitive challenges. In the United States alone, that adds up to millions of people who, long after the pandemic ends, may still be dealing with the consequences of the disease.

The urgency of supporting these patients has led to a push for greater collaboration, new technologies and perhaps most important of all, an openness to really listen to long COVID patients, believing in and using their experiences to shape future research.

What is long COVID?

To inform potential treatments, researchers aim to better characterize the causes of and variations in long COVID’s wide range of symptoms. Currently, long COVID tends to be defined broadly (SN: 7/29/22). The U.S. Centers for Disease Control and Prevention characterizes it as a “wide range of ongoing health problems” that can last for months after infection with SARS-CoV-2, the virus responsible for COVID-19.

The electronic health records that researchers use to study long COVID aren’t comprehensive, however, due to gaps in the data. Records often focus disproportionately on people who could get a PCR or antibody test, were hospitalized and had predominantly respiratory symptoms, says Lisa McCorkell, a public policy researcher and cofounder of the Patient-Led Research Collaborative, a group of long COVID patients who also have research experience.

What’s more, records “do not document all of the symptoms the patient experiences,” she says. And for many patients, information about different symptoms can be spread across different healthcare systems, making it difficult for researchers to connect the dots.

“A long COVID diagnosis can mean so many different things in your physiology are going wrong,” says David Putrino, director of rehabilitation innovation at the Mount Sinai healthcare system in New York City and leader of one of the first labs to focus on long COVID. More comprehensive tracking of patients’ symptoms, he says, is crucial to better understand how long COVID presents itself and document how it impacts patients’ lives.

To achieve this goal, experts say, future data collection must be designed collaboratively. Coordination between patients and researchers helps ensure studies are asking the right questions, while coordination between experts with different specialties promotes multidisciplinary, creative approaches to a condition that impacts every organ system in the body. Coordination between research groups in different locations is also important for producing inclusive datasets.

New studies currently in early phases across the United States provide models for how scientists can work with patients and across specialties to investigate long COVID, learning from mistakes made earlier in the pandemic. The results of this work could inform strategies for patients to manage their symptoms and lead to potential treatments.

Asking the right questions

Some of the most influential research on long COVID so far has come from patients themselves, including a 2021 study from the Patient-Led Research Collaborative that documents more than 200 potential symptoms.

“Patients know the right questions to ask to properly document their experience,” McCorkell says. This can include which symptoms are studied, how data are collected from patients and how groups of patients are compared.

For example, one common flaw in research design is that potential long COVID patients might be included in a study’s control group (that is, with the assumption that they do not have the condition) because they lack a positive test result or “do not have the exact symptoms a study defines as being long COVID,” McCorkell explains. Since many long COVID patients — especially those who got sick early in the pandemic — lack positive test results, such a control group can skew study findings because researchers are comparing two groups of people that, potentially, both include patients with long COVID.

To avoid these problems, researchers can solicit feedback from patients during all parts of the scientific process. The Patient-Led Research Collaborative required this type of engagement for applicants to a $5-million research fund run by the collaborative: The winning projects, announced on November 22, were reviewed by a panel of patient experts and will incorporate further patient feedback throughout the research process.  

Putrino’s lab is taking a similar approach in setting up a new clinic focused on long COVID and other complex, chronic illnesses. The lab has a “lived experience advisory board” that responds to questions ranging from how the clinic’s waiting room should be set up to how healthcare workers ask patient survey questions, Putrino says.

Surveys have become a particularly valuable tool in long COVID research, filling the gaps left by electronic health records. Health records are “the clunkiest part of this research,” says Arjun Venkatesh, a patient-reported outcomes researcher at Yale University who is investigating COVID-19’s long-term impacts. While new web applications and legislation have made it easier for patients to access their medical records, researchers still face many technical and data security barriers to connecting datasets from different health systems.

Venkatesh and his colleagues use surveys to collect basic information, such as a patient’s vaccine record, as well as metrics that typically wouldn’t be in an electronic health record, such as their fatigue levels over time. In setting up these surveys, it’s important to solicit input from patients, Venkatesh and others say. Filling out a survey could trigger common long COVID symptoms like brain fog or post-exertion pain and fatigue. Responsible researchers ask a small group of patient volunteers to test surveys before they are widely released.

Input from patients is also crucial in designing clinical trials for long COVID, says Julia Moore Vogel, a program director at the Scripps Research Translational Institute in San Diego. People living with the condition have spent time reading studies, comparing notes and testing out symptom management techniques. “There’s actually a decent amount of anecdotal data we can use to inform trials,” she says.

Anecdotal data inspired a study that Vogel, a long-hauler herself, is starting. She is aiming to enroll 5,000 patients who will test how well a wearable device helps them manage their symptoms, using a technique called pacing. Some Garmin health trackers have a feature called “body battery,” which combines several measurements to determine the user’s capacity for exertion. Vogel and other long-haulers use this feature to monitor their activity, stopping to rest when their “battery” gets low. Her new study aims to test the strategy on a larger scale.

Making connections across specialties and locations

The number of people impacted by long COVID is unprecedented. But the condition shares many characteristics with other complex, chronic diseases that arise after infections and affect multiple organ systems, such as myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS. These conditions have historically received limited research funding even though they impact millions of people — a problem attributed in part to the diseases’ inability to fit into a specific medical specialty, says Jaime Seltzer, director of scientific and medical outreach at the ME/CFS advocacy group #MEAction, which is based in Santa Monica, Calif.

Funding from the National Institutes of Health, for example, is allocated to research groups through the agency’s topic-focused institutes and centers. “Every disease is supposed to neatly and nicely fit into these categories,” Seltzer says. “And if it doesn’t, everyone goes, ‘It’s not my problem.’” Conditions like ME/CFS and long COVID also are not taught in medical schools, leading to a general lack of awareness among doctors about how to properly diagnose them, she says, which results in incomplete datasets.

To push back against this fractured system, doctors and researchers need to collaborate across specialties, experts say. Scientists with different types of expertise are starting to work together to design comprehensive studies, share data and educate each other about new techniques. The Long COVID Research Consortium is one such group: Researchers with different specialties are investigating the condition’s underlying biology, with data shared across the participating teams.

“We’re going to be setting up our own data-sharing platform,” says consortium member Richard Scheuermann, director of informatics at the J. Craig Venter Institute in La Jolla, Calif. Data from studies of long COVID patients’ microbiomes, immune systems, lungs and other areas will all be in “the same database,” he says, enabling research that connects the different body systems.

Collaboration between scientists in different places is also crucial to producing research that reflects a diverse patient population. One example is the National Institutes of Health’s RECOVER initiative to learn about the long-term health effects of COVID-19 (SN: 10/24/22).

The initiative’s adult study has recruited about 10,000 people from 53 sites all over the United States and Puerto Rico. But Putrino would like to see the federal government go further by recruiting more patients, collaborating more closely with patient advocacy groups, educating providers and integrating research with efforts to directly help long-haulers, such as aid with disability benefits applications.

Create “a set of common data elements that every site collects, so that every site around the country can contribute to a national registry of people with long COVID,” Putrino says. Such a registry, similar to existing registries for cancer patients, would help researchers better understand the different potential subtypes of long COVID and provide a large population ready to volunteer for clinical trials.

As researchers recruit for large studies of long COVID, they should reach out to communities that are less educated about the condition, says Dona Kim Murphey, a physician, neuroscientist and long-hauler based in Houston. “How do you reach the folks who don’t even know to come to you?” she asks. Public education campaigns about long COVID — combined with easier access to healthcare for people facing long-term symptoms — can contribute to more comprehensive patient datasets (SN: 11/3/22).

Some long COVID researchers are using new technology to better understand the condition, such as wearable devices, survey apps and machine learning for analysis. But models for comprehensive, collaborative research that includes all patients with a complex condition don’t need to be reinvented. As an example, Seltzer points to a 2014 CDC initiative to study autism, in which 11 sites across the country worked together to diagnose children while simultaneously educating clinicians about autism.

“They basically had diagnostic experts in autism train other people to become diagnostic experts in autism,” she says. The study is a model in creating an inclusive dataset, while simultaneously enabling a new group of researchers to better study a condition in the future. Seltzer hopes to see federal agencies enable similar large-scale studies for long COVID and related conditions.

As some long COVID patients enter their fourth year with the condition and more people continue to get infected, moving toward impactful clinical trials is a top priority for scientists. “Design research in a way that’s going to be most effective to the end users, who are the patients,” says Vogel, the Scripps researcher. Going forward, this research model could be valuable for other complex diseases, too.

For the first time, astronomers have observed how certain supermassive black holes launch jets of high-energy particles into space — and the process is shocking.

Shock waves propagating along the jet of one such blazar contort magnetic fields that accelerate escaping particles to nearly the speed of light, astronomers report November 23 in Nature. Studying such extreme acceleration can help probe fundamental physics questions that can’t be studied any other way.

Blazars are active black holes that shoot jets of high-energy particles toward Earth, making them appear as bright spots from millions or even billions of light-years away (SN: 7/14/15). Astronomers knew that the jets’ extreme speeds and tight columnated beams had something to do with the shape of magnetic fields around black holes, but the details were fuzzy.

Enter the Imaging X-Ray Polarimetry Explorer, or IXPE, an orbiting telescope launched in December 2021. Its mission is to measure X-ray polarization, or how X-ray light is oriented as it travels through space. While previous blazar observations of polarized radio waves and optical light probed parts of jets days to years after they’d been accelerated, polarized X-rays can see into a blazar’s active core (SN: 3/24/21).

“In X-rays, you’re really looking at the heart of the particle acceleration,” says astrophysicist Yannis Liodakis of the University of Turku in Finland. “You’re really looking at the region where everything happens.”

In March 2022, IPXE looked at an especially bright blazar called Markarian 501, located about 450 million light-years from Earth.

Liodakis and colleagues had two main ideas for how magnetic fields might accelerate Markarian 501’s jet. Particles could be boosted by magnetic reconnection, where magnetic field lines break, reform and connect with other nearby lines. The same process accelerates plasma on the sun (SN: 11/14/19). If that was the particle acceleration engine, the polarization of light should be the same along the jet in all wavelengths, from radio waves to X-rays.

Another option is a shock wave shooting particles down the jet. At the site of the shock, the magnetic fields suddenly switch from turbulent to ordered. That switch could send particles zooming away, like water through the nozzle of a hose. As the particles leave the shock site, turbulence should take over again. If a shock was responsible for the acceleration, short wavelength X-rays should be more polarized than longer wavelength optical and radio light, as measured by other telescopes.

That’s exactly what the researchers saw, Liodakis says. “We got a clear result,” he says, that favors the shock wave explanation.

There is still work to do to figure out the details of how the particles flow, says astrophysicist James Webb of Florida International University in Miami. For one, it’s not clear what would produce the shock. But “this is a step in the right direction,” he says. “It’s like opening a new window and looking at the object freshly, and we now see things we hadn’t seen before. It’s very exciting.”

Humans aren’t the only animals known to move to a musical beat.

For instance, parrots do it, too. And now rats have been observed bopping their heads in time with the music of Mozart, Lady Gaga, Queen and others, researchers report on November 11 in Science Advances.

What’s more, the animals seem to respond to the same tempos that get humans’ feet tapping. The study could help reveal the evolutionary foundations of humans’ sense of rhythm.

“Some of us believe that music is very special to human culture. But I believe that its origin is somehow inherited from our progenitors,” says Hirokazu Takahashi, a mechanical engineer at the University of Tokyo, who studies how the brain works.

The ability to recognize the beat of a song and synchronize the movements of one’s body to it is known as beat synchronization. It’s a mystery why some species, like humans and parrots, have the innate ability and others do not (SN: 4/30/09).

For rats in the lab, Takahashi and his colleagues put on Mozart’s “Sonata for Two Pianos in D Major” (K. 448). The team sped up and slowed the tempo, as well as played it at its normal speed, observing the rats’ motions not only visually, but also with wireless accelerometers, which were surgically placed on the rats.

The team initially thought that body size might determine the tempos that triggered any head bopping. Humans tend to prefer foot tapping to music that’s between 120 to 140 beats per minute, but a small animal like a rat would probably need a quicker tempo to get that same reaction, the researchers hypothesized.

“There’s lots of reasons to think maybe [rats] would prefer faster rhythms. But that’s not what they found. And that’s intriguing,” says Aniruddh Patel, a psychologist at Tufts University in Medford, Mass., who was not involved in this research. He studies music cognition, the mental processes involved in perceiving and responding to music.

In the video recordings, the rats’ head bobbing was more pronounced when the sonata played at its usual tempo, around 132 beats per minute. The same was true for 20 people who listened through headphones with accelerometers.

For both humans and rats, the head bopping was consistent at about 120 to 140 bpm. When the music was played faster or slower, then there was no head bopping. That suggests that there is something fundamental about how the animal brain is tuned or wired to respond to rhythm, Takahashi says.

The team also played some of their favorite pop songs for the rats, including Lady Gaga’s “Born This Way” and Michael Jackson’s “Beat It,” and saw a similar response.

While Patel agrees that rats seem to prefer beats that humans like, he is not convinced that the rats can synchronize to the beat like humans do.

“I think that that study actually raises more questions than answers in some sense,” Patel says. Humans and parrots show beat synchronicity through big, voluntary movements like head bobbing, dancing or foot tapping. The rats displayed very tiny movements that needed to be captured with special devices like a head-mounted accelerometer and motion capture technology.

The behavior was also more observable when the researchers lured the rats to stand on their back legs by putting their water bottle up high, compared with being on all fours.

“The fundamental nature of beat perception and synchronization is that you predict the timing of the beat and you move predictably” he says. “So, we land right on beat or a little ahead of it.” Since the rats’ movements are so tiny, it’s not clear if rats can predict the beats or if they’re just reacting to it.

Both Takahashi and Patel stress that this study does not show that rats like to dance to human music. “Music stimulus is very appealing to the brain,” Takahashi says. “But it is not evidence [that] they enjoy or they perceive music.”

Next, Takahashi is looking to see what other aspects of music we might share with rodents and other animals. “I’d like to maybe reveal how other properties, like melody and harmony, also relate to the dynamics of the brain.”

A sacrificed spider monkey is shedding new light on an ancient Mesoamerican relationship. 

The remains of a 1,700-year-old monkey found in the ancient city of Teotihuacan outside modern-day Mexico City suggest the primate was a diplomatic gift from the Maya. The find is the earliest evidence of a primate held in captivity in the Americas, researchers report November 21 in Proceedings of the National Academy of Sciences. 

Unearthed in 2018 at the base of a pyramid in Teotihuacan, the monkey’s skeleton lay beside the corpses of other animals — including an eagle and several rattlesnakes — in an area of the city where visiting Maya elites may have resided.

Evidence of animal sacrifices, including of predators like jaguars, have been found in the city before. But “up to that point, we did not have any instances of sacrificed primates in Teotihuacan,” says Nawa Sugiyama, an anthropological archaeologist at the University of California, Riverside.

Chemical analysis of the spider monkey’s bones and teeth showed that the female had likely been captured in a humid environment at a young age sometime in the third century. The monkey then lived in captivity for a few years before meeting her end between the years 250 and 300.

The highlands around Mexico City are a long way from the natural habitat of spider monkeys (Ateles geoffroy), which require wet tropical forests to thrive. This fact, along with the presence of Maya murals and vessels, suggests to Sugiyama and her colleagues that the spider monkey was a gift from elite Mayas to the people of Teotihuacan. 

The find is an example of diplomatic relations between two cultures that sometimes had violent interactions. Maya hieroglyphs indicated that military forces from Teotihuacan invaded the Maya city of Tikal in 378, marking the start of a roughly 70-year period in which Teotihuacan meddled in Maya politics (SN: 10/22/21).

The “striking” discovery of the monkey shows that relationship between these two cultures far predates the invasion, says David Stuart, an archaeologist and epigraphist at the University of Texas at Austin who was not involved in the study.

“The war of 378 had a long history leading up to it,” he says. “The monkey is a really compelling illustration of this long relationship.”

Marsupials may have richer social lives than previously thought.

Generally considered loners, the pouched animals have a wide diversity of social relationships that have gone unrecognized, a new analysis published October 26 in Proceedings of the Royal Society B suggests. The findings could have implications for how scientists think about the lifestyles of early mammals.

“These findings are helpful to move us away from a linear thinking that used to exist in some parts of evolutionary theory, that species develop from supposedly simple into more complex forms,” says Dieter Lukas, an evolutionary ecologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who was not involved with the study.

Mammals run the gamut of social organization systems, ranging from loose, ephemeral interactions like aggregations of jaguars in the South American wetlands to the antlike subterranean societies of naked mole-rats (SN: 10/13/21; SN: 10/20/20). 

But marsupials — a subgroup of mammals that give birth to relatively underdeveloped young reared in pouches — have traditionally been considered largely solitary. Some kangaroo species were known to form transient or permanent groups of dozens of individuals. But among marsupials, long-term bonds between males and females were thought rare and there were no known examples of group members cooperating to raise young. Previous work on patterns of mammalian social evolution regarded about 90 percent of examined marsupial species to be solitary.

“If you look at other [studies] about some specific species, you will see [the researchers] tend to assume that the marsupials are solitary,” says Jingyu Qiu, a behavioral ecologist at CNRS in Strasbourg, France. 

Sorting social lives

Qiu and her colleagues developed a database of field studies that illuminated marsupial social organization, taking into account how populations vary within a species and delving into the evolutionary history of marsupial social lives. The researchers compiled data from 120 studies on 149 populations of 65 marsupial species, categorizing each population as solitary, living in pairs — such as one male and one female — or falling into four kinds of group living, including one male and multiple females (or vice versa), multiple males and females, or single sex groups.

While 19 species, or 31 percent of those studied, appear to go strictly solo, nearly half of the species always live in pairs or groups. The team also found lots of variation within species; 27 of the 65 species — more than 40 percent — fell into multiple social organization classifications.

When the researchers looked at this social variation against climatic conditions in Australia, they found that social variability was more common in drier environments with less predictable rainfall. It’s possible that being able to switch between solitary and group living acts as a buffer against resource unpredictability. 

The researchers’ focus on social flexibility “highlights that there is nothing simple even about a supposedly solitary species,” Lukas says. 

Implications for the earliest mammals

Qiu and her colleagues also ran computer analyses comparing the evolutionary relationships of the marsupials with how they form social relationships. This let the team predict the social organization of the earliest marsupials, which split from placental mammals about 160 million years ago. Because modern marsupials have been considered solitary, the marsupial ancestors — and the earliest mammals on the whole — have generally been assumed to be solitary as well.

The team found that solitary was the most likely social category of the ancestral marsupials, a 35 percent probability. But Qiu points out that the varied combinations where pair and group living are possible options make up the other 65 percent. So “it is more likely that the ancestor was also non-solitary,” she says. The findings also give insights into the range of possible lifestyles experienced by the earliest mammals, she says. 

But Robert Voss, a mammalogist at the American Museum of Natural History in New York City, questions the analyses’ insights about a potentially social ancestral marsupial. The uncertainty about the solitary alternative, he says, is largely due to the researchers’ benchmarks for what does and what doesn’t constitute social behavior — thresholds that Voss views as too permissive. For example, Voss disagrees with the team’s characterization of opossum social organization.

 “Anecdotal observations of [members of the same species] occasionally denning together is not compelling evidence for social behavior,” says Voss. “None of the cited studies suggest that opossums are anything other than solitary.”

Future work, Qiu says, will involve gathering data on a larger subset of mammals outside of marsupials to get a clearer picture of how social traits have evolved among mammals.