Popular Science

The European Space Agency’s (ESA) Euclid space telescope went to work in 2023 with a clear directive—scour the cosmos for dark matter and dark energy. But while these mysterious targets theoretically compose upwards of 95 percent of the entire known universe, there are still plenty of other subjects for the two-ton observer to examine.Over 60 million subjects, to be specific.

Astronomers recently directed Euclid to pause its normal duties and instead examine the Milky Way galaxy’s stunningly luminous interior, also known as a galactic bulge. The telescope’s visible-light camera sensitivity is on par with the Hubble Space Telescope’s wide-field lens, but with an exponentially larger vantage. In only a few hours, Euclid can image an area about 270 times larger than what Hubble can accomplish. The result is the sharpest visible light photo ever captured of the Milky Way core. The stellar image features more than 60 million stars as well as numerous stellar clusters and nebulae.

Two zooms show the staggering resolution of Euclid’s image. The most zoomed-in vignette on the lower right corresponds to 0.003% of the galactic bulge survey area (which is 4.8 square degrees in total). With many thousands of stars discernible in this tiny area, the entire Euclid galactic bulge image charts no less than 60 million stars. Credit: ESA/Euclid/Euclid Consortium/NASA, CFHT, ESA/Gaia/DPAC, image processing by J.-C. Cuillandre and E. Bertin (CEA Paris-Saclay)

The new photo is far more than a simple flex of Euclid’s power. The data contained inside is helping researchers understand otherwise hard-to-examine cosmic interactions like microlensing. A form of gravitational lensing, microlensing events only occur when two stars perfectly align in an observer’s line of sight. The star crossing in front of the other one brightens and bends the latter object’s light, thereby acting like a giant magnifying glass. The same situation also occurs for any nearby planets, allowing astronomers to identify otherwise invisible subjects.

“To catch microlensing, you need to observe parts of the sky that are crowded with stars, such as close to the center of our galaxy,” Jean-Philippe Beaulieu, a survey contributor from Institut d’Astrophysique de Paris, said in a statement.

Beaulieu explained that nearly 300 new exoplanets have been discovered using this method over the last 20 years, all through the use of telescopes here on Earth.

“This image from Euclid includes 51 known planetary systems—and it will assist in studying many more that will be found,” he added.

This infographic places Euclid’s galactic bulge survey in the broader context of the Milky Way’s structure, using data from ESA’s Gaia mission. The top row shows schematic views (artist impressions) of our spiral galaxy: an edge-on view highlighting the central bulge (top left), a top-down view revealing the spiral arms and the survey region (top centre), and a zoom into the galactic disc indicating the location of the Solar System (top right), from where Euclid observes the sky, which turns into the main background of the visual. The lower panel illustrates the diversity of objects captured by Euclid as it observed towards the galactic bulge in March 2025. Moving from left to right, the numbered cutouts highlight dense molecular clouds that obscure background starlight, a glowing emission nebula associated with recent star formation, a young star cluster, and finally the galactic bulge itself – a dense, spheroidal region containing ten billion stars. This crowded central region provides ideal conditions for detecting microlensing events. Credit: Euclid images: ESA/Euclid/Euclid Consortium/NASA, CFHT, image processing by J.-C. Cuillandre and E. Bertin (CEA Paris-Saclay); Milky Way artist impressions: ESA/Gaia/DPAC, Stefan Payne-Wardenaar)

Spotting a new microlensing event typically takes over 20 days of examination, meaning Euclid’s 24-hour photo session can’t be used to find new examples. Instead, astronomers can begin assessing the mass of already known exoplanets while also preparing for yet-to-be-identified objects.

“In 24 hours, Euclid has already captured the stars involved in all the future microlensing events that the Roman Space Telescope will detect, but before the stars and planets involved have aligned,” added said survey contributor Natalia Rektsini. “This means that anyone who detects a microlensing event in the same region, for example with Roman, will be able from now on to use Euclid data as a time reference in the past and see how the stars looked before they overlapped.”

NASA is currently gearing up for the Roman Space Telescope’s launch in August 2026. Until then, there is still time to add your name to its cargo ahead of its journey into orbit.

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We share 98.9 percent percent of our DNA with many of our primate cousins, but we also may share something a little more silly. Modern humans and great apes may have been laughing for at least 15 million years. The findings, published today in the journal Communications Biology, shed new light on how our speech evolved. 

“How did humans evolve the remarkable ability to speak? Speech leaves no fossils, and complex language exists only in our own species,” Dr. Chiara De Gregorio, a study co-author and primatologist at the University of Warwick, said in a statement. “But we’ve found a 15-million-year-old clue in an unexpected place: our laughter.”

All living great apes (orangutans, bonobos, chimpanzees, gorillas, and humans) laugh. However, it’s been unclear how laughter may have changed the past several million years of evolution and how it may relate to human speech evolution. 

In this new study, a team from the University of Warwick in the United Kingdom analyzed recordings from four orangutans, two gorillas, four chimpanzees, three bonobos, two gorillas, and four humans. They found the same pattern across 14 laughter sequences—all six species laugh with evenly spaced rhythmic intervals between successive sounds.

According to the team, this basic rhythmic structure was likely already present in a shared common ancestor 15 million years ago. This structure has also remained with all living great apes over all that time, since all great apes show the same underlying speech pattern.

“By comparing how different species laugh, we can see that a basic rhythmic structure has remained unchanged since our last common ancestor,” De Gregorio said. “That’s extraordinary.”

A bonobo smiling. Image: Elisa Demuru.

While the basic rhythm has stayed constant, human laughter has changed a bit. It’s become faster, more variable, and gained sophisticated control that is dependent on the context. Humans are the only great apes that have this ability to (mostly) control when and how they laugh depending on the situation. An uncontrollable laugh when tickled is vastly different from a polite laugh in a meeting, an infectious laugh during a movie, or a nervous little giggle after making a mistake. That same underlying rhythm in laughter is shaped by a conscious control to communicate varying emotions and intentions.

These findings suggest that throughout great ape evolution, our ancestors gradually developed more control over the timing of their vocalizations, including laughter. Scientists consider sophisticated vocal control like this as a fundamental building block of speech.

Since laughter has such deep evolutionary roots and has remained shared by all living great apes for millennia, it is one of the easiest ways to study how the vocal transformations changed across hominid evolution.

“Contrary to the classic notion that the first humans suddenly acquired vocal control capacities remarkably different from their predecessors, laughter evolution tells us that humans lay on a continuum, a prolongation of vocal control capacities that were already being cumulatively honed in for 15 million years,” study co-author and primatologist Dr. Adriano Lameria concluded. 

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With the recent Artemis II mission to the moon, humanity is again starting to explore the possibility of astronauts spending long periods of time in space—perhaps even one day going to Mars, even if doing so sounds pretty awful. Still, for all the chest-beating talk of looking to the stars, there’s one question that you rarely hear asked: Would humanity be able to reproduce in space? And more specifically, how would space affect pregnancy and birth?

Dr. Varsha Jain of the University of Edinburgh is one of surprisingly few researchers considering these questions. She’s been referred to as a “space gynaecologist”—although she says that technically, “my proper title is that I’m an OB-GYN and clinical academic”—and has written and spoken extensively about the question of whether we’ll be able to have babies in space. While, in theory, one could be pregnant and potentially even give birth in space, Jain says, there are just too many questions that remain unanswered for either to be very safe. 

Space’s effects on reproductive health

The first question that comes to mind is how one even researches a topic like this. There’s no empirical data, insofar as no one has ever been to space while pregnant, and it’s not like we can do double-blind studies by launching pregnant women into space to see what happens. Does this mean that we’re relying entirely on hypothesis and theory?

Yes and no, says Jain. “What we do have,” she explains, “are studies that have been done in other environments or on other species: For example, rodents have been pregnant and been into space. So we can try to understand what is happening to their bodies and their physiology.”

There are also situations on Earth that can provide insight: For example, parabolic flights, where passengers experience a short period of weightlessness or reduced gravity, simulating the gravitational environment of space travel.

Ultimately, one of the biggest limits on our knowledge­ is the lack of data about the effects of spaceflight on women’s bodies. 

There’s not a lot of information about how space affects women’s bodies. Period. 

“A lot of that information we do have [about the effects of space flight on the body] has come predominantly from male subjects and male participants,” Jain says. 

“In a lot of the textbooks about human physiology [and] what happens to the human body in space, the chapters on cardiovascular health, lung health, kidney health,” she says, “all of those chapters are based predominantly on male astronauts. So it would be really great to write an entire book where the chapters are focused on female health, rather than having one chapter on the sex-based differences.”

Ironically enough, it’s the lack of understanding of women’s bodies that is responsible for this scarcity of data. The first woman in space, Soviet cosmonaut Valentina Tereshkova, orbited the Earth 48 times in a three-day mission during 1963, but it took NASA another 20 years to send a female astronaut into orbit. Even today, six men have been to space for every woman. 

Not to mention, in the past, NASA engineers haven’t exactly shown an exemplary understanding of women’s bodies to begin with. In 1983, engineers famously packed 100 tampons into legendary astronaut Sally Ride’s “crew equipment” bag for a single week in space—along with a make-up kit. 

“[They] asked me, ‘Is 100 the right number?’” Ride later sighed. “I said, ‘No. That would not be the right number.’”

Seen on the flight deck of the space shuttle Challenger, astronaut Sally K. Ride, STS-7 mission specialist, became the first American woman in space on June 18, 1983. Image: NASA Radiation would pose real risks for pregnant women

Even without empirical data, there are several fairly obvious risks that space would pose to both pregnant people and babies. The first is the high volume of background radiation. Space looks empty, and there’s fewer gases, molecules, and atoms in a given volume of space than there is here on Earth. Unfortunately, the stuff that is there tends to be dangerous, because it’s moving really, really fast.

Take the example of galactic cosmic radiation. This specific type of radiation comes from beyond our solar system and is “composed of the nuclei of atoms that have had their surrounding electrons stripped away and are traveling at nearly the speed of light,” according to NASA. 

On Earth, our planet’s atmosphere and magnetic field protect us from these fast-moving particles. In space, however, the particles are free to rocket through pretty much anything in their path. As they do, they can ionize the atoms they encounter, knocking electrons clear of their atomic nucleus. NASA describes this sort of radiation as being “like an atomic-scale cannonball that blasts through material, leaving significant damage behind.”

This can lead to all sorts of negative health outcomes, from cataracts to cancer—and, as per the World Health Organization, children are “significantly more sensitive to radiation exposure than adults.” 

Jain says that as an OB-GYN, she “would think really hard, long and hard” before sending a pregnant woman for a single X-ray because of the dangers of radiation. Doses of radiation are measured in Sieverts (Sv), with a chest X-ray providing a dose of 0.1 mSv. According to NASA, meanwhile, “astronauts are exposed to ionizing radiation with effective doses in the range from 50 to 2,000 mSv.” That’s an awful lot of chest X-rays.

It’s no surprise, then, that Jain identifies radiation exposure as “the number one biggest worry that would be on my mind” about the idea of sending a pregnant woman to space.

Other reasons pregnancy in space could be really bad

However, radiation is not the only concern. The lack of gravity is also a potential problem for a body that’s both under strain and undergoing significant changes from carrying a child. 

“We know that microgravity has an impact on muscles and bone,” Jain says. “That would be of concern to me because your muscle and bone distribution also changes during pregnancy. When you add those two [factors] together, what does that mean?”

Ultimately, we don’t know, Jain says. But it could be bad. 

The International Space Station (ISS) jointly operated by space agencies in the United States, Russia, Europe, Japan, and Canada. Image: SCIEPRO / Getty Images SCIEPRO

And there are also less obvious potential dangers. She cites a study examining mice giving birth in a microgravity environment, noting that these mice “had twice as many labour contractions than the ground controls. And we found later that there was an issue with one of the proteins in the muscle of the womb.”

It’s impossible to know how many other such dangers lurk for pregnant women in space. And then there’s the question of giving birth.

What would happen if you gave birth in space?

So could a woman give birth in space? Jain says that in theory, there’s no reason why not, although “it would be difficult and stressful for any number of reasons, some of which we know, and some of which we don’t.” 

As with giving birth on the ground, there’s an awful lot that can go wrong, and both the dangers and the question of how to deal with them would be more profound in space. “I wouldn’t be as concerned about vaginal birth [in space],” Jain says. “But what I would be concerned about is [what would happen if] there was a problem.”

What, for instance, if a caesarean section was required? “Probably somewhere near to a quarter to a third of babies are born on average by caesarean section,” Jain says. “We’ve never done an operation at that scale [in space].” Time would also be of the essence, and as Jain points out, “things don’t happen very quickly in space.” Performing surgery in microgravity would be very hard.

Even if we could magically conjure up a fully equipped labor ward on the International Space Station, the mere fact of being in space would again present added dangers. For a start, the lack of gravity does strange things to fluids: “If I was doing an operation—for example, a caesarean section—there’s no way I would want blood forming and coalescing in front of me,” says Jain. “So [that environment] adds different dynamics to the situation.”

And, again, there’s the effect of the environment on the human body. “There’s something called space flight anemia,” Jain says, “and we know that on Earth, starting at a lower blood count level is a risk factor for bleeding at labour. [That means that] for postpartum hemorrhage, being anemic is a risk factor—so that [would] already start to worry me.”

Perhaps the most profound implication of considering questions like these is the light they throw onto what’s already happening—or not happening—back here on Earth, where our understanding of women’s bodies and women’s health still lags behind that of men in any number of ways. 

“Are there other areas I’d like to see research in?” Jain says. “Sure. All of it.”

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

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A pair of sibling gas giants originally spotted by citizen scientists are so lightweight that their density resembles wispy cotton candy more than a standard atmosphere. The rare duo detailed today in the journal Monthly Notices of the Royal Astronomical Society even have an appropriate technical term to describe them. TOI-791 b and TOI-791 c fit the bill for “super-puff” planets.

“Only a handful of these super-puffy planets are known, and it is even rarer to find two in the same system,” George Dransfield, a study co-author and University of Oxford astrophysicist said in a statement. “Their extremely low densities make them fascinating targets for understanding how planetary systems form and evolve.”

The two planets are situated about 1,110 light-years from Earth, in the southern constellation of Volans.TOI-791 b has a density of 0.022 and TOI-791 c has a density of 0.027 ounces per cubic inch. To put those numbers in perspective, Earth possesses a density of 3.18 ounces per cubic inch, while Jupiter (our solar system’s largest planet) exhibits an average of 0.76 ounces per cubic inch. And while both of these puff planets are roughly the same size as Jupiter, they are about 28 to 35 times denser. For a more tangible, tastier frame of reference, the spun sugar used in cotton candy has a density of about 0.29 ounces per cubic inch.

Comparison of the exoplanets in the TOI-791 system with planets in our solar system. Image: NASA / Daniel Rutter

TOI-791 b and TOI-791 c were flagged as candidate planets about four years apart by volunteers combing through data collected by NASA’s Transiting Exoplanet Survey Satellite (TESS), as part of the Planet Hunters TESS citizen-scientist project. For eight years, astronomers around the world combined efforts to study the two objects, using observatories including the exoplanet telescope at Concordia Station in Antarctica.

Researchers examined each planet’s transit in front of its host star to measure how much they dimmed the stellar light. These tiny calculations then helped the team estimate their size, mass, and other properties. Only four other systems are known to include super-puff planets, but the team discovered details that make the latest additions even more unique. TOI-791 b and TOI-791 c are united by what’s known as a 5:3 mean-motion resonance—a seldomly seen gravitational relationship that makes the inner planet orbit five times for every three orbits of the outer planet.

Dr. George Dransfield and colleagues with the Antarctic telescope, ASTEP (Antarctic Search for Transiting ExoPlanets), during a summer service mission in 2021/2022. Image: Karim Agabi / IPEV / PNRA

“These multi-planetary systems are complex, with gravitational interactions between the planets that evolve over very long periods, tens of years or more,” added study co-author and astronomer Tristan Guillot.

Astronomers still aren’t quite sure how super-puff planets came into existence. One prominent theory hypothesizes they contain huge atmospheres rich in hydrogen and helium that formed while the planets orbited far from their host star inside colder areas of a protoplanetary disc. Going forward, the researchers plan to continue studying TOI-791 b and TOI-791 c to gain a better understanding of super-puff planets, including potentially enlisting the powerful James Webb Space Telescope.

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An asteroid as large as five cruise ships is barreling towards Earth at 5.6 miles per second. Civilization thankfully isn’t in any imminent danger, but the cosmic debris will still come close enough to possibly spot using only a pair of strong binoculars.

The asteroid (152637) 1997 NC1 will pass closest on June 27 at around 7:15 a.m. EDT. It , when it will only be about 1.59 million miles away—over six times the distance between Earth and the moon. Discovered nearly two decades ago, (152637) 1997 NC1 likely measures somewhere between 820 and 1,800 yards-wide based on its reflective sunlight, although astronomers say it may be a bit smaller. 

Stargazers in the Northern Hemisphere will be able to see the space rock during its approach in dark enough conditions, while those living in the Southern Hemisphere can catch a glimpse as it begins departing this corner of the solar system. That said, seeing 1997 NC1 may be a bit more difficult thanks to the lunar cycle.

At its closest, the asteroid will be over six times the distance between the Earth and the moon. Credit: ESA

“A close approach to Earth by an object this size only occurs every few years, although this time the bright nearby moon might impede its observability at closest approach,” European Space Agency Planetary Defense Office information specialist Juan Luis Cano said in a statement.

Earth is no stranger to asteroid encounters, with the oldest evidence of a cosmic impact dated to around 3 billion years ago. Luckily, truly devastating events are comparatively rare from a geological standpoint. The space rock that led to the dinosaurs’ extinction slammed into the present-day Gulf of Mexico about 66 million years ago, while the last major example known as the Tunguska Event occurred in 1908. The roughly 180-foot-wide meteor’s explosion above a remote region of Russia released the energy equivalent of three to 50 megatons of TNT while leveling about 830 square miles of Siberian forest.

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This fluorescent bat did not fly into bright yellow road paint or dive into a bowl of saffron. It’s covered in pollen. 

Lesser long-nosed bats (Leptonycteris yerbabuenae) are some of the animal kingdom’s lesser-known pollinators. The medium-sized bats primarily live in arid grasslands, desert scrublands, and dry tropical forests. In North America, female lesser long-nosed bats migrate from south-central Mexico up to the southwestern United States in the spring. They follow “nectar corridors” of columnar cacti and agave plants.

From brush-tipped tongues to bodies covered in fine hair that gathers pollen, the lesser long-nosed bat is a perfectly-designed pollinator. Image: NPS.

According to the United States Department of the Interior (DOI), this particular bat ended up covered in pollen after stopping on a blooming agave plant.

“As it travels from flower to flower, the bat helps pollinate the plants that support desert ecosystems and produce crops we rely on,” the DOI writes. “And yes, agave pollination also plays a role in helping make tequila possible.”

Lesser long-nosed bats are so linked to tequila that they are commonly called the ‘tequila bat.’  They pollinate agave plants, which are then used to make tequila and mezcal. When they feed on cactus fruits and nectar, they may also help disperse cacti seeds.  

A lesser long-nosed bat sips nectar from a cactus flower (and isn’t covered in pollen). Image: Bruce Taubert/Bat Conservation Inc. via USFWS

While the lesser long-nosed bats are considered near threatened, they are a conservation success story. In 2018, it became the first bat species to be taken off of the Endangered Species Act, after 30 years of conservation efforts. 

These bats and other pollinators such as bees, butterflies, beetles, and moths are all being celebrated during National Pollinator Week (June 22–28, 2026). While critical to our entire ecosystem, habitat loss, pesticides, pathogens, and changes in land use among other impacts threaten the pollinators. According to the USDA Animal and Plant Health Inspection Service, the number of managed honey bee colonies in the United States dropped from five million in the 1940s to roughly 2.68 million in 2023.  

To help protect the planet’s pollinators, a growing number of home gardeners and cities are planting pollinator gardens. Native plants can attract and house the pollinators needed to grow fruits, vegetables, and other plants that we need to survive. Backyards can even be transformed into bat hangouts, so that these power pollinators and insect eaters have a place to rest.  

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Around 465 active geysers are roiling across Yellowstone National Park at any given time, with new ones regularly bubbling to the surface every year. But as impressive as they are, they’re best appreciated at a distance. And there’s a new pool of boiling water to avoid, thanks to an event that began almost two years ago. 

On July 23, 2024, a hydrothermal explosion burst from Biscuit Basin’s Black Diamond Pool, sending a 400 to 600 foot plume of mud, rock, and scalding water into the air. No one was injured, but park geologists have kept the area closed to visitors ever since.

After months of relative calm, monitoring tools began picking up a low-frequency acoustic signal known as infrasound along with anomalous seismic reading in the basin on June 13, 2026A visit to the site later that day revealed an unexpected sight—a roughly 3.7-mile waterway called Firehole River wasn’t its typically clear color. Instead, the currents were tinted with opaque, light-gray sediment. On top of that, two additional runoff channels had appeared.

A review of sensor data indicated only a small rise in heat before slowly returning to ambient air temperature, which differed from quick drops seen in previous eruptions at Black Diamond Pool. This eliminated Black Diamond as a likely suspect—so what caused the odd readings?

Thankfully, a nearby livestream camera previously installed by the Yellowstone Volcano Observatory revealed the culprit. At 5:09 a.m. local time, a dark jet of water shot from the ground north of Black Diamond Pool that matched the seismic and infrasound upticks. Geologists returned to the site the following day and confirmed a large amount of hydrothermal water had flowed into Firehole River via three new sets of vents. These vents offered a route for underground water that reached boiling temperature and flashed into steam, causing the explosion that rose tens of feet into the air.

Pool of boiling water that formed a few days after the June 13, 2026, hydrothermal explosion at Biscuit Basin, Yellowstone National Park, and that is located near the middle vent group of features that formed during the explosion. Credit: Yellowstone National Park

Researchers noted only one vent was still funneling water into the river, but it was a sizable opening at 61-feet-long and upwards of five-feet-wide. The water was also around 194 degrees Fahrenheit—near the 200-degree boiling temperature at that elevation. A subsequent return visit two days later showcased an even more incredible find. In a matter of hours, the eruption vents had formed a pool of boiling, silty water measuring 21-by-17 feet. A lack of surrounding debris confirmed the natural bath formed from an underground collapse instead of a separate explosion. Further camera footage captured multiple geysers measuring 20 to30 feet high.

Given all that activity, Biscuit Basin will remain closed to visitors for the foreseeable future. Thankfully, the geologic events can still be appreciated thanks to the impressive video feeds.

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In archeology, the truth lies in the teeth. Our hearty chompers can withstand the test of time, preserving precious genetic data that can help tell the stories of long-deceased animals—and also complicate those narratives. Several teeth discovered in a South African cave system point to a potentially all-female burial site belonging to one of our more mysterious extinct human cousins. More than just fossils, the teeth indicate that these relatives may have had complex cultural practices as well as some odd genetics. The findings are detailed in a study published today in the journal Cell.

Homo naledi is an extinct cousin of our species, Homo sapiens. First discovered in South Africa’s Rising Star Cave system between 2013 and 2015, Homo naledi lived in present-day South Africa between 225,000 and 241,000 years ago. Very little is known about their life on Earth, since scientists have not found many fossils or tools associated with Homo naledi. The limited information that we have primarily comes from their teeth. They show an unusual mixture of primitive and ape-like traits, alongside more human features.

For more than 10 years, scientists have wondered why the adult fossils discovered in the cave’s Dinaledi Chamber looked so identical. The remains showed almost none of the physical variations normally present between males and females. To figure out why, an international team investigated the proteins lurking inside of the skeletal remains. They used a minimally destructive acid etching technique to protect the teeth, while also extracting microscopic fragments from inside of them called peptides. In total, they extracted peptides from 23 teeth representing 20 different individuals. 

With the precious peptides in hand, they analyzed the tooth enamel for Amelogenin-Y. This protein is only coded by the male Y chromosome, and indicates that an individual was biologically male. 

The team did not find any of this male genetic marker inside of the tooth enamel.  To double check this puzzling result, they analyzed the amino acids to prove that the proteins were genuinely ancient and not the result of contamination.

“The lack of male markers with the group is truly fascinating,” Dr. Marc Dickinson, a study co-author and University of York analytical chemist, said in a statement. “It is incredibly exciting to gain a window not only into the biology of our ancestors, but also into how they lived.”

This potentially all-female burial site opens up new questions regarding Homo naledi’s culture and social structure. If the chamber was reserved just for females, it could imply a level of complex and symbolic burial practice that was previously believed to be unique to modern humans.

However, there could be a biological explanation for the burial as well as a cultural one. According to the team, it’s possible that the Homo naledi population was highly isolated, causing the male-specific Amelogenin-Y gene to mutate or be deleted entirely. In this case, males would have been present, but their teeth did not have the typical genetic signature seen in other male teeth.

“Unlike those found in other remains like bone fragments, proteins in tooth enamel are preserved because dental enamel—the hardest tissue in the human body—shields proteins from environmental contamination even for millions of years,” added Palesa Madupem, a study co-author and palaeoproteomicist at the University of Copenhagen. “This makes them ideal carriers of genetic information from deep time. Our study helps in the long-standing mystery of why Homo naledi lacked significant variation; it’s probably because they could have all belonged to one sex.”

These ancient females or genetically unique males are shaking up what scientists thought they knew about the dawn of human society and our extinct relatives. 

“These findings offer rare insights into a culture that has, until now, been difficult to access directly,” Dickinson said. “Advances in ancient protein analysis are opening the door to a far richer and more nuanced understanding of ancient hominins.” 

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I’m writing this very sentence while sitting in a so-called “body doubling” session. On an open Zoom screen are the friendly, if focused, faces of fellow writers. Cameras are on, audio is muted, and I know we’re all working on similar tasks. That’s because we’ve shared our to-do list in the chat. When the hour wraps up, we’ll celebrate what we’ve accomplished and move on with our days. 

Body doubling—a focus technique where friends, colleagues, or classmates work alongside one another to stay on task or power through difficult work—is fairly new to me. But the concept has been floating around the internet for years. It took off during the pandemic as we sat at home, struggled to focus, needed a little accountability, or just wanted to see some friendly faces. It’s especially touted in the neurodivergent community, including among those with ADHD, as a way to direct attention toward a task they’re not excited about.

But body doubling isn’t a quick fix for everybody, Will Canu, a licensed psychologist and psychology professor at Appalachian State University, tells Popular Science. Canu’s research interests include attention-deficit disorders, and he was one of the founders of AsUR, Appalachian State’s intensive student support program for, primarily, first and second-year students with executive functioning challenges. The program helps students build new academic habits and self-management skills to navigate the college transition and to support long-term academic success.

Body doubling works for some, and there are plausible scientific reasons why, Canu says. But that doesn’t mean it’s a hack that solves every focus challenge, whether the individual has ADHD or not. 

“Some people with ADHD may actually do worse body doubling than by being by themselves and reducing distraction,” Canu says. “It may really be something that depends a lot on who you are.” 

What is body doubling? 

Exactly what constitutes body doubling depends on who you’re talking to. For Canu, it’s intentionally having a partner who is there to help facilitate your work. “Not necessarily actively,” he says. They’re “not giving you tips” he adds, “but being there with you and not being distracting.” 

Russell Ramsay, a clinical psychologist who specializes on adults with ADHD and co-founded the University of Pennsylvania’s Adult ADHD Treatment and Research Program, sees body doubling a bit more broadly. It could include classmates in a study group, walking buddies, personal trainers at the gym, or people trading services, such as “I’ll help you clean out your closet if you help me clean out my garage,” Ramsay tells Popular Science.

People practice body doubling in various ways, including virtually or in person. A growing industry of apps, such as Focusmate and Focus Space, along with live streamers on social media, also market themselves as a way to boost productivity with others. 

Why body doubling might work

While headlines swirl around body doubling, there aren’t any large, randomized trials to show it works. “Despite the theoretical possibility of this being something that’s beneficial, we don’t have evidence that it is, besides anecdotal evidence,” Canu says. That gap prompted him to study the question a few years ago. 

During the 2022 to 2023 academic year, Canu and fellow researchers added a few questions about body doubling to a larger survey of 1,600 students across seven college campuses. About 10 percent had ADHD. Their research found that while some with ADHD preferred to work with someone else, the boost in performance wasn’t huge and they weren’t seeking it out more than students without ADHD. 

The two groups, however, differed in why they wanted to work with others. For students with ADHD, accountability was the top reason to study with another person, the research found. Those without ADHD were more likely to say it made studying more fun, or that they simply had someone available to lean on for help if needed. 

Around 8.4 percent of children and 2.5 percent of adults experience ADHD, Attention-Deficit/Hyperactivity Disorder. Video: What is ADHD? | APA, @AmericanPsychiatricAssociation

Some theories exist around why body doubling might work for some of us. For example, Ramsay notes, body doubling draws on the fact that we’re a social species. It works by externalizing motivation, turning a private intention into a shared plan. That social commitment, plus the anticipation of meeting someone, can create a kind of dopamine “wave” that pushes people through tasks. 

“A little bit of face time and that social contract helps,” Ramsay says. 

Tips for a body doubling session

Does body doubling sound like something you want to try? Here are some tips about how to get started. 

1. Pick the right partner: Look for someone who will work during the session and not spend the hour chatting. Finding partners who do similar work, such as a classmate or co-worker, can help. If you get stuck, your partner is more likely to understand the task and normalize the struggle.

2. Create a simple structure: Start with a quick check-in where each person states a specific, actionable goal for the session. Work quietly for a defined period, then end with a quick debrief on what got done. Regularly scheduled sessions and clear time boundaries—a set block, such as an hour—can keep tasks manageable and sustainable, Ramsay says. 

3. Evaluate honestly: Don’t expect body doubling to work for you, Canu advises. Try it a few times, and then evaluate the results honestly. Did you actually focus better and get more done? Or were you more distracted, drained, or resentful?  

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Body doubling isn’t for everyone

Canu worries that people, especially those with ADHD, will see the hype around body doubling, assume it’s a proven solution to work on undesirable tasks and then either skip better-supported treatments or feel discouraged if it doesn’t work for them.

“What bothers me is that it’s described by some as being this kind of miraculous thing, and everyone with ADHD should do it,” Canu says.

If it works, great, he says. But if you’re still struggling with getting a task done, other approaches work well and even better. Canu points to evidence-supported strategies such as breaking big tasks into smaller chunks, working at your own optimal time of day, and using low or no-cost timers or apps, such as Pomodoro-style tools, that reward sustained focus.

“There are lots of other things that you can do to maximize your effectiveness,” he says. 

For me, some days a body doubling session is exactly what I need. Other days, I just need to step away from the computer and take a walk to get back on track. And that’s fine too.  

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

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In 2025, paleogeologists announced the discovery of the world’s oldest known asteroid impact. Trace evidence of the strike is still standing in northwest Australia, and the team estimated the region known as the North Pole Dome (NPD) formation dated back around 3.5 billion years ago.

However, the timeline needs to be corrected a bit after months of further analysis. But at roughly 3 billion years old, however, the asteroid strike still remains the most ancient example of a cataclysmic interstellar event on Earth. The details are laid out in a study published today in the journal Geology and hinge on miniscule trace minerals.

“The impact left a ‘mineral clock’ behind. By dating minerals that were remade or newly grown in the damaged rocks, we can now pin down when this extraordinary event happened,” Chris Kirkland, a Curtin University planetary scientist and study co-author, said in a statement.

Kirkland explained the central evidence resides in the tiny, resilient mineral called zircon. At the NPD structure, some traces exhibited unique, skeletal shapes indicating they formed under extreme conditions.

“We interpret these as impact-modified crystals, formed when older zircon was disrupted, partly recrystallised, and in places regrown during the intense heating caused by the impact,” he said. These zircon crystals point to an event about three billion years ago, which is their best estimate so far about the age of the impact.

To further solidify their theory, Kirkland and colleagues also looked at apatite. This second mineral only forms while hot fluids transfer through rocks damaged by shocks. The dates on the apatite and zircon aligned within the same 3 billion-year-old window.

“The agreement between two different mineral systems gives us confidence that we are seeing the signature of a single major event—a meteorite impact,” said Kirkland.

The evidence reinforces the NPD structure as the oldest asteroid impact ever discovered. It also remains the only asteroid impact confirmed from the Archean Era about 4–2.5 billion years agoTKTK. The rarity of such ancient events is owed to Earth’s ever-shifting geology. Although imperceptible to humans, the planet’s rocky surface and interior are constantly influenced by immense pressure, heat, and fluids. This means that particularly ancient evidence like the NPD impact almost never survives to the present-day.

“This discovery pushes Earth’s impact record deeper into geological time than any previously well-dated crater, offering a rare glimpse of the violent processes that shaped the early Earth,” said Kirkland.

Although the oldest known to researchers, the NPD structure is far from the most famous. The Chicxulub impactor struck Earth much more recently, about 66 million years ago. And while that doesn’t earn it any timeline records, it is largely responsible for wiping out the dinosaurs.

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In yet another lesson about the great circle of life, Sandy and Luna are getting ready to leave the nest. Over the weekend, Luna began going out further on one of the tree limbs surrounding the nest. Called the “front porch,” this limb does not have any nest underneath to protect the birds, so exploring it can be a bit dangerous. Sandy also briefly stepped out on the front porch, before getting her talon stuck on a twig that appeared to put her off balance. However, Sandy did get in some good wing tests. 

While preparing to fledge, the pair are flapping their wings frequently. 

“While Shadow was playing a little hide and seek in the quiet of the Twin Pines, Luna was busy displaying a close-up demonstration of his wing’s ability on the back porch of the nest,” Friends of Big Bear Valley (FOBBV) writes. “Sandy practiced her wingers on the front porch all while firmly gripping her talons on the branches. Luna, however, could not pass up another chance to show off his beautiful wing for the camera.”

Both eagles are right on target to fledge, and will keep venturing out further on the branches to test out winds and build their confidence.  Sandy and Luna will turn 11 weeks old this weekend and Big Bear eagle chicks generally fledge at around 13 weeks, give or take a few days. Based on past eaglets, they may return to the nest for food, sleep, or a little hang out from time to time. They also generally stay near parents Jackie and Shadow for about one month, learning how to fish and be adult eagles.

Jackie and Shadow’s 2026 babies: Everything you need to know

It’s been another roller coaster nesting season for Jackie and Shadow, a pair of internet-famous bald eagle parents living in San Bernardino National Forest in Southern California. After two of their eggs were destroyed by ravens in January, Jackie and Shadow laid two new eggs that have successfully hatched.

Chick 1 hatched on April 4 at 9:33 p.m. PDT, while Chick 2 followed on April 5 at 8:30 a.m. Their large nest in Big Bear Valley east of Los Angeles is livestreamed 24 hours a day by nonprofit Friends of Big Bear Valley (FOBBV) and has captivated millions. 

On May 1, FOBBV announced the chicks’ names: Sandy and Luna.

How long will the chicks stay in the nest? 

Chicks usually stay in the nest until 10 to 14 weeks of age.

What challenges do the eaglets face?

Before leaving the nest, the chicks face threats from other birds of prey, including hawks, ravens, other eagles, and owls. Inclement weather can also present challenges for the chicks. In 2025, a March snowstorm resulted in the death of one of Jackie and Shadow’s three chicks.

During fledging, only 70 percent of eaglets survive. One of the greatest threats is from cars that can injure or kill the birds while they scavenge for food on roadkill. 

Who are Jackie and Shadow? 

The pair first got together in 2018 and successfully raised chicks in 2019 and 2022. However, their eggs failed to hatch in 2023 and 2024. Only 50 percent of eagle eggs successfully hatch, so this pair has already beaten the odds.

What happened to Jackie and Shadow’s 2025 eaglets?

In 2025, Jackie laid three eggs that all hatched in early March. On March 13, a strong snowstorm dumped up to two feet of snow and battered the nest with strong winds. Only two of the chicks were visible on the live cam when the storm passed by the next morning. FOBBV later confirmed the passing of one of the chicks. The two surviving chicks were later named Sunny and Gizmo after 54,000 names were submitted by fans.

What happens after chicks fledge? 

Young eagles usually fledge–or leave the nest and fly–when they can flatten their wings and have feathers capable of flight. This typically occurs when the birds hit 10 to 14 weeks of age. Males also tend to take their first flight a little sooner than females. 

According to FOBBV, fledglings from Southern California have been spotted as far south as Baja California, as far north as British Columbia, and as far east as Yellowstone National Park.

About 70 percent of bald eagles survive the fledgling stage. FOBBV does not tag their eagles, so it’s not possible to follow the chicks’ journeys after they flee the nest.

Can I help Jackie and Shadow?

Yes. Environmental groups are currently fundraising $10 million to protect Jackie and Shadow’s foraging area from development. Learn more at SaveMoonCamp.org.

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Researchers have officially solved a shipwreck mystery that has plagued historians for nearly 30 years—the identity of a ship discovered off the southern coast of England in 1995. The ship is the ill-fated Dutch trading ship Dom van Keulen, which left Morocco for the Netherlands in the fall of 1633 with a hefty cargo that included more than 9,000 gold coins. But just before reaching home, the ship sank off the coast of England. The ship’s identity and its legacy are detailed in a new book From Morocco to the Coast of England: The Story of the Dom van Keulen and its Remarkable Cargo. 

Historian Ian Friel uncovered documents chronicling the Dom van Keulen’s final voyage in the United Kingdom’s National Archives. The crew “met with much tempestuous weather,” and the ship eventually sprang a leak. The large ship wrecked near the coastal town of Salcombe, 30 miles southwest of Plymouth.  

Luckily, all of the crew survived, and most of the cargo was likely salvaged shortly after the sinking. According to Dave Parham, a marine archeologist at Bournemouth University who helped edit the new book, the ship was loaded with 150 bags of gum arabic (a tree gum used in thickening), 64 bags of saltpeter (used in gunpowder), 320 goat skins, and 9,000 Barbary ducats and other gold Moroccan coins.

These coins and goods originated from the Barbary Coast (present-day Morocco). In the 16th and 17th centuries, Dutch merchants actively traded manufactured goods for pure West African gold from the Sa’dian Sharifs. This Arab Sharifian dynasty ruled Morocco between 1549 and 1659. Around the same time, the Netherlands had a large maritime industry and a global trading empire that spanned five continents. Dutch officials melted down the West African gold to make their own coins, which became one of the most widely accepted trade currencies in the world.

A diver above the wreck site with cannons below on the sea bed. Image: Maritime Archaeology Sea Trust (MAST).

400 of the ship’s gold coins remained embedded in the seabed until 1995, when a team from the South West Maritime Archaeology Group discovered the wreck. 

The coins themselves provide “important context for the wealth and architecture of the Sa‘dian Sharifs, the trade in African gold, and tangible evidence of the flourishing 17th-century maritime trade linking Morocco, the Low Countries, and Britain,” Parham added in a statement.

Other recovered artifacts include: a pewter bowl and spoon, a ceramic sounding weight shaped as a pilchard, stamp seal, and finger nugget. Image: British Museum.

According to the team, very little is known about theDom van Keulen’s size and appearance, and no known paintings of the ship exist. The wreck site itself is about 98 feet-long and is about 60 feet below the surface. The wreck site is still littered with cannons, anchors, and other small items of cargo. The British Museum owns several items from the wreck, including a pewter bowl and spoon, gold jewelry, a weight in the shape of a fish, a stamp seal, and pottery.

In 1995, “the discovery of African gold from under the sea off the coast of Devon was an amazing discovery that raised so many questions about how it came to be there,” added Jeremy D. Hill, the head of research at the British Museum. 

Now, we finally know the exact ship that carried the gold-laden cargo. “The story can now be told of how a Dutch ship carrying North African gold was wrecked off the English coast, making this a discovery of international importance,” said Hill. “It reminds us how much there is still to be found under our seas.”

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Wine grapes from Texas will soon join worms, human sperm, and cookie dough on a growing list of Earth objects sent to space. Hundreds of grape seeds will spend about six months being exposed to cosmic radiation on the International Space Station (ISS). The seeds will then return to Earth for planting. They might even be turned into wine. If so, they’d become the first wine ever made from grape seeds that traveled through space, much like a meteorite-infused vodka. 

This experiment is part of the Texas A&M/Aegis Aerospace Multi-Use Space Platform Integrating Research and Innovative Technology (TAMU-SPIRIT) research mission. The project is designed to serve as a “satellite campus in space,” that will host several experiments. 

Texas A&M seniors Coby Arnold and Arvind Subramanyam built the carrier that will bring the seeds to the ISS as their senior capstone project, under the guidance of Texas A&M viticulture specialist Justin Scheiner. Once the seeds leave the protection of Earth’s atmosphere, the extended exposure to space radiation could induce genetic mutations. According to Scheiner, the carrier will protect the seeds from harmful radiation exposure that could damage the seeds and prevent them from sprouting.   

Once they are back on Earth, the seeds will be planted next to identical control seeds at the AgriLife Research vineyard at Thomas Ranch in central Texas. Scientists will then study differences in plant growth, vine and wine grape performance, and genetics between the seeds that went to space and the control seeds.

Three wine grape varieties were chosen to go to space based on their disease resistance and adaptations to soils and water conditions that help them thrive in Texas vineyards. One of three grape varieties is called lomanto. Horticulturist and pioneering viticulturist T.V. Munson developed the variety in 1902.  Called “the grape man of Texas,” Munson and his lomanto grape is credited with helping save the global wine industry. 

In the late 1800s, tiny aphid-like insects called phylloxera destroyed many of France’s vineyards. Lomanto is a hardy vine that is naturally resistant to several diseases and droughts, and Munson sent lomanto vines to help fortify French vineyards. Scheiner said this new mission represents a “full circle” moment for the historic vine with roots in the Lone Star State.

“The research will help us understand how different levels of radiation impact the seeds and their varietal genetic expression once we grow them, but there is also the novelty that in several years we will potentially be bottling wine from seeds that left Earth,” Scheiner said in a statement. 

Testing the seeds in such a stressful and alien environment could help scientists produce more resilient, adaptive, and productive plants. The knowledge gained from experiments like this and understanding mutations could benefit future space missions and crop production on Earth. 

Mutations have long shaped horticulture and wine production throughout for centuries. For example, pinot gris originated from just one mutation that yielded the ever popular pinot noir wine grapes. 

“From a research standpoint, we want to see how being in space might influence these varieties,” Scheiner said. “For the wine geek in me, it would be very interesting if these seeds show some random positive mutation.” Who knows maybe the next pinot noir will come from space seeds?

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They may have tiny bodies, but fruit flies produce giant sperm. Adult male Drosophila melanogaster fruit flies are about two millimeters long (roughly the size of a sesame seed) and their sperm can be just as long, with the sperm tails taking up most of that space. 

In order to keep the thousands of sperm cells inside their bodies untangled, the insects use movement in an ingenious way. The sperm cells are organized into densely aligned groups that move by pushing off one another to keep themselves more taut. The more taut, the less likely it is that the tails will get tangled. The findings are detailed in a study published today in the journal Nature Physics.

Fruit fly sperm are about 40 times larger than human sperm, and thousands of sperm cells are stored inside the tightly confined spaces of both the male and female reproductive systems. One of those organs is the seminal vesicle, where males store the sperm before mating. 

The seminal vesicle is only about 200 micrometers in size. That’s really small compared to the sperm cells that are two millimeters long. In theory, this cell-to-storage size ratio should be similar to putting a pair of wired earphones inside of a pants pocket. The earphones often come out as a tangled mess.

“Now imagine putting thousands [of earbuds] in your pocket. The sperm are of course different from passive wires: the sperm are active, generating bending waves along their long tail,” Jasmin Imran Alsous, a study co-author and computational biologist at the Center for Computational Biology, tells Popular Science. “So how do thousands of active sperm organize and move within the tight confines of the reproductive system?”

To see how male fruit flies keep so many lengthy sperm organized, the team dyed the sperm’s heads and tails with a fluorescent substance and examined them with a powerful 3D electron microscope. They saw that the sperm cells are densely packed, but instead of staying still, they generate collective movements. These movements, called flows, can span the entire seminal vesicle for hours at a time. 

According to Imran Alsous, individual sperm move smoothly past each other, similarly to cars moving along a highway in opposite directions. 

Microscopy image of a giant fruit fly (Drosophila melanogaster) sperm. Its head is colored magenta and tail is cyan. The sperm cell is also to scale with the much smaller human sperm. Image: Jasmin Imram Alsous.

“Each sperm is attached to a long tail, that tail is moving just as quickly as the heads, but the tails collectively move more slowly together, in this flowy slow churn. It would be as if the highways now began to fold and bend while the cars within them continued to dart in opposite directions,” she explains. 

The team believes that these forces help to keep the sperm cells’ long tails from getting tangled in both male and female reproductive organs. The contact-based interactions help them move by pushing off of each other, which keeps the cells more taut, instead of a mushy mess.

Another example of these tight-packed systems in biology is how six feet of DNA is stored inside of a cell nucleus or how humans’ large and small intestines are about 30-feet-long when combined. This set-up allows living things to store more than their bodies should allow. For sperm cells, this increases the chance reproduction will be successful and the species will survive. 

“Our work suggests that sperm can move in a way that’s very different from the textbook picture of a lone sperm swimming through fluid,” says Imram Alsous. “Individually, fruit fly sperm exhibit very little directed motion, but together they can move through interactions with their neighbors.”

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While warfare seems like a deeply human conflict, a tiny carnivore also makes its own strategic moves before battle.

The warriors in question are common dwarf mongooses (Helogale parvula), the smallest carnivore in Africa. They are native to parts of East to southern Central Africa, including Angola and Zambia and some provinces in South Africa. They live in communities of five to 30 individuals, and when different groups meet, potentially dangerous fights usually ensue. 

According to a study recently published in the journal Nature Ecology & Evolution, these mammals predict meeting rival groups and change how they communicate, move, and protect resources before it happens. The research demonstrates that these groups change their behavior in regions with the  greatest chance of rival fights, even if there is no other group. Additionally, the greatest changes take place in the face of the highest predicted danger. 

“We know that battles between groups can be very dangerous for participants. What we’ve shown now is that there are constant behavioural changes to mitigate these risks and enhance the likelihood of future contest success,” Andy Radford, senior author of the study who teaches behavioral ecology at the University of Bristol, said in a statement.

Dwarf mongoose acting as a sentinel (raised guard) gathering and conveying information to groupmates about potential rival threats. Image: Shannon Wild.

The team observing dwarf mongooses in South Africa noted that individuals keeping an eye out for incoming danger call out more if it’s a larger group that poses the possible threat. On the other hand, certain behaviors, like selecting where to snooze in the evening, shift most in the presence of well-matched neighbors with whom conflict can be most damaging.

“Not only are the mongooses keeping track of where their enemies might be, but they’re factoring in the relative size of different groups. They can then tailor their pre-emptive behaviour accordingly,” said Josh Arbon, lead author of the study and behavioral ecologist at the University of Cambridge. “This work provides insight into how smaller groups are able to survive, and even thrive, amongst more powerful enemies by strategically moving through space and communicating about potential dangers.”

Radford, Arbon, and colleagues used 10 years of observational and GPS data collected in South Africa for their research. 

Ultimately, “conflict between groups is rife throughout the natural world,” said Amy Morris-Drake, a co-author of the study and biologist at the University of Bristol. “We have shown that animals are continuously making decisions in a landscape of conflict, not just when they actually encounter rivals.”

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Cataracts are a common eye condition marked by a cloudy lens that can be extracted fairly easily. For humans, anyway. But on June 12th, the patient on the operating table wasn’t a person—it was a lion. 

Experts diagnosed an African lion (Panthera leo) named Tsavo with cataracts over half a year ago. He was rescued as a cub in 2013 and currently lives at Wildlife Safari, a wildlife park and conservation center in Oregon. Last week, his veterinarian team successfully carried out the eye operation. It should improve the lion’s quality of life significantly and represents an international effort, with experts using equipment from around the world. 

Tsavo was diagnosed with two cataracts in 2025. Image: Marcus Doshi.

The surgical process started at around 2 p.m., and less than three hours later the team had removed the two cataracts and replaced them with custom-made artificial lenses. At 5:15 p.m. Tsavo was back in the Lion Hut, where he started his recovery under the watchful eye of the wildlife park’s carnivore team. 

“One of the most surprising things is that the surgery itself is almost identical to modern human cataract surgery,” Cassandra Bliss, a veterinary ophthalmologist at Bliss Animal Eye Care who co-led the entire team, tells Popular Science. “The biggest differences are the anatomy and the patient. A lion’s eye is significantly larger than a human eye, requiring specialized calculations and a much larger artificial lens.”

Tsavo was rescued as a cub in 2013. Image: Marcus Doshi.

The successful operation was the result of months-long preparation and coordination among veterinary professionals and medical technology experts from across the planet. Tsavo now has clear visual pathways again, and he is also expected to regain his binocular vision and depth perception. 

Tsavo receiving diagnostic imaging from a Butterfly Network ultrasound. This ultrasound technology provided the clinical insight needed to plan and perform the procedure.  Image: Marcus Doshi.

“Vision is one of the primary ways lions interact with their environment,” Bliss explains. “Restoring sight isn’t just about seeing again, it’s about allowing an animal to navigate its world, engage with enrichment, recognize familiar caretakers and companions, and express the natural behaviors that contribute to its quality of life.”

Benjamin Alcantar, Head Veterinarian at Wildlife Safari was the other co-lead. He and Bliss had previously carried out cataract surgeries on two Wildlife Safari lions last year. 

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In the animal kingdom, fatherhood exists on a spectrum. Some species like grizzly bears or lions will leave after mating and never really interact with their offspring again. Others do everything from keeping eggs warm solo to carrying their young in their mouths and even giving birth. 

“By the male investing in offspring it increases the chance of their survival, and specifically the survival of his genes,” Karen McDonald, an educational specialist at the Smithsonian Environmental Research Center tells Popular Science. 

“Male-only parental care is rare in mammals and vertebrates, but it’s surprisingly common in ray-finned fish (over 50 percent of families), with many species caring for large broods of their offspring from different females. In birds, male-parental care is less than one percent of the species.”

Here are some of the unique ways that some animals experience fatherhood. 

Seahorses and their little ‘fry’

Seahorses are the unofficial poster species for animal fatherhood. While the female produces the eggs, the male is the one who gets pregnant. After mating, the female transfers her eggs to a brood pouch on the male’s tail for him to fertilize. 

“Crazy cool fact, the seahorse brood pouch is really like a placenta,” McDonald explains. “It does the same things, with respiratory gas and waste exchange, salinity regulation, nutrient supplementation, and immune protection. Essentially it’s what is confirmed as a ‘vertebrate pregnancy.’”

The male then cares for the eggs for roughly two to four weeks and before releasing the babies–called fry. Depending on the species, they can have anywhere from five fry  up to 2,000 at one time. Having as many babies as possible is critical since only about one in 200 will survive. 

A lined seahorse (Hippocampus erectus). Image: Jonathan Irons/Smithsonian Environmental Research Center Water bugs and their egg glue

Some aquatic animals like giant water bugs (aka toe biters) make use of a staple found in human dad’s tool chest—glue. 

“Eggs are laid by the female onto the males’ dorsum or back using a protein-based egg glue,” McDonald explains. 

The water-resistant secretion helps the eggs stay in place. Depositing the sperm directly helps the male insect ensure paternity.

Three-spine stickleback and hidden nests

Like giant water bugs, male three-spine stickleback fish (Gasterosteus aculeatus) also make use of glue, but with a twist. They use a sticky secretion from his kidneys called spiggin to cobble together marine debris and algae into a tunnel-like nest. 

“The male spiggin or kidney glue that is used to glue the nest has genetic plasticity, allowing for nest construction based on the environment they are in,” McDonald says. “The male can actually tune the chemistry of the glue to match the water chemistry, so that it holds it together better and can adjust to the environment.”

Once he’s ready to breed, his belly turns red and he performs a special zig-zag dance for the female. She will then take a look at the den he built and deposit the eggs. She leaves after fertilization and he will then stay to protect them.

Greater rheas and their single dad skills

If seahorses are the poster species for males who can give birth, greater rheas (Rhea americana) are a model for stay-at-home dads. These large, flightless birds will build nests for their mate’s eggs, take care of all the incubation, and then rear the chicks alone and keep them safe. 

“Rheas are the largest birds in South America and among the largest birds in the world,” Sara Hallager, Curator of Birds at the Smithsonian’s National Zoo and Conservation Biology Institute, tells Popular Science. “Adult greater rheas don’t have many predators but large cats (cougar, puma, jaguar) native to their range can take down an adult. Chicks and juveniles are the most vulnerable, but once a rhea reaches adult size, they are usually pretty safe.”

Arapaima and their amazing mouths

Native to the Amazon River, arapaima are one of the largest freshwater fish in the world and don’t have many natural predators. For their tiny babies, also called fry like seahorses, it’s a whole different world. To keep them safe, arapaima dads suck their young into their mouths when they sense danger. They then swim to a safe area and release them.

“Arapaima will build a nest and females can lay anywhere from 20,000 to 50,000 eggs,” Rebecca Sturniolo, Curator for Amazonia and American Trail at the Smithsonian’s National Zoo and Conservation Biology Institute, tells Popular Science. “Both parents will defend the nest.”

These big fish also breathe air at the surface of the water, to help them survive in habitats with lower levels of oxygen. 

Arapaima are one of Earth’s largest freshwater fish. Image: Smithsonian Institution. Abby Wood Golden lion tamarins and their teaching skills

Golden lion tamarins (Leontopithecus rosalia) are small monkeys found in the trees of Brazil’s Atlantic coast. After birth, their young will spend a few weeks with their mother to nurse. Then, it’s all about dad. Baby golden lion tamarins will cling to dad and ride along wherever he goes.

“Babies are learning the sights, sounds, and smells of the forest,” Kenton Kerns, a curator and biologist at the Smithsonian National Zoo and Conservation Biology Institute, tells Popular Science. “They’re learning what ‘safe’ feels like, what ‘danger’ is, how to react to other animals or other golden lion tamarins. They’re learning what adult tamarins eat by watching dad, how they move, where it’s best to sleep.”

Golden tamarins spend a lot of time with their dads. Image: Smithsonian Institution. Jessie Cohen

Golden lion tamarins were critically endangered until 2003, when they were upgraded to endangered. When they were brought to the zoo during the 1970s, the Smithsonian team and Brazilian researchers collaborated to figure out how much paternal care these primates need. 

“Zoo staff kept the dads in the with the babies, which was a bit unorthodox with primates at the time,” says Kerns. “That change allowed a boom of babies in zoos and led to the eventual reintroduction of zoo-born golden lion tamarins to Brazil.”

Happy Father’s Day!

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It’s like something out of an old-school Looney Tunes cartoon: a gorilla, sound asleep and snoring in his nest high in a tree, suddenly stands up and takes a few steps. For the gorilla, this would be a very short story with a very bad ending.

Humans, on the other hand, sleepwalk all the time. It’s a behavior that has fascinated and freaked us out for centuries, from the hand-wringing somnambulism of Lady Macbeth to the strange murder cases involving Ambien-induced sleepwalking. We find the condition unsettling, mysterious, and even funny, possibly because it violates a fundamental idea—that sleep is a state of stillness, of surrender. 

Yet some humans seem to have missed that memo. Sleepwalking affects an estimated five percent of children and 1.5 percent of adults. Which raises an interesting question: Why us?

Other animals have their own versions of restless sleep: the dog’s paws paddling as if in mid-chase, the cat’s whiskers twitching in annoyance at some imaginary unwanted affection. But true sleepwalking, involving standing, walking, and navigating obstacles, has not been documented in other species. 

“Humans are probably not unique in having odd motor events during sleep, but sleepwalking as we define it is overwhelmingly human,” says David R. Samson, associate professor of evolutionary anthropology at the University of Toronto and author of the new book The Sleepless Ape: The Story of Sleep in Human Evolution.

So, why do only humans do this? The answer has everything to do with where our ancestors slept.

What happens when you sleepwalk?

Sleepwalking primarily occurs during deep non-REM sleep, says Samson, who describes sleepwalking as a “state dissociation.”

“Parts of the brain involved in movement and arousal come online while regions involved in reflective awareness, judgment, and memory remain in a sleep-like state,” he says. 

In practical terms, this means the body can do surprisingly complicated things—navigate stairs, open doors, wander down a dark hallway—while the part of the brain responsible for awareness, judgment, and memory remains essentially asleep. Which is why sleepwalkers can appear eerily purposeful while having absolutely no idea what they’re doing.

In sleepwalking, as Samson puts it, “the body can move before the waking mind has fully arrived.”

Perhaps one of the most famous sleepwalking scenes comes from Shakespeare’s Macbeth when Lady Macbeth emerges night after night in a “slumb’ry agitation.” Image: Public Domain

Samson has a fairly straightforward explanation for why humans sleepwalk while a sleeping gorilla in the tree stays put. Nearly all primates sleep off the ground—on branches, in tree holes, on sleeping platforms—which means a sleepwalking primate would likely fall or be killed. 

“Selection would be severe,” says Samson.

Sleepwalking is a glitch, not a feature 

Samson doesn’t see sleepwalking as a behavior that evolved for a purpose. Instead, he says, it’s a rare flaw in an otherwise finely tuned sleep system.

“For most primates sleeping in trees, this vulnerability would be catastrophic,” he says. “But in the human ‘sleep shell’—with socially buffered camps, shelters, fire, bedding, and shared vigilance—the immediate penalty of getting up from sleep may have been reduced.”

In other words, the communal safety net our ancestors built for themselves at night did the protective work that staying perfectly still once did. 

This is an especially compelling example of “relaxed selection.” In relaxed selection, certain unfavorable traits are able to persist because the environment doesn’t weed them out.

Natural selection didn’t get rid of sleepwalking in humans, because our early environment didn’t punish sleepwalkers. It likely shielded them “once our ancestors began sleeping in safer, socially protected ground sites,” says Samson.

The body moves, but nobody’s home

A large part of what makes sleepwalking so disorienting—for both walkers and witnesses—is the gap between what’s happening on the outside and what’s happening on the inside. Samson has observed this firsthand in a close friend and colleague with a history of sleepwalking episodes.

“One night, I was walking down a dark hallway to use the bathroom when I saw his silhouette at the other end. Suddenly, he charged toward me, grabbed me, and we ended up in a brief, bewildering struggle in the hallway,” he says. “Then, just as abruptly, he stopped, turned around, and went back to bed as though nothing had happened.”

The next morning, Samson’s friend had no recollection of the skirmish in the hallway, but gave his own vivid account of a much higher-stakes struggle.

“When I told him what happened, he said that in his dream, a wall of lumber was falling on me and he was trying to save me,” Samson says. 

“That, to me, is one of the most striking things about these episodes: From the outside, the behavior can look sudden, physical, and even alarming, but from the inside, the dream logic may be protective, purposeful, and emotionally coherent.”

Sleepwalking runs in the family 

The protective “sleep shell” might explain why humans have the luxury of being able to sleepwalk, but the evolutionary story gets even more interesting when you look at who actually sleepwalks.  

Genetics plays a clear role, Samson says, though there’s no single “sleepwalking gene.” It’s more of a knack for sleeping so deeply you can’t quite claw back up to the surface—a knack that tends to run in families.

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Sleepwalking also shows up more often in childhood, when deep non-REM sleep is most prevalent and the brain’s sleep-wake cycles are still maturing. Genetics plays a role here, too. Having a mom or dad who sleepwalks definitely increases your chance of plodding to the kitchen while catching some Z’s. 

One longitudinal study found that children with no family history of sleepwalking had about a 22 percent chance of sleepwalking themselves. But that jumped to 47 percent with one sleeping parent, and 61 percent when both parents were sleepwalkers.

“There is clearly a familial, genetic component,” says Samson.

Most of us file sleepwalking away as a quirk, a punchline, or a far-fetched plot device. But Samson says it can also reveal important things about your health.

“Sleep deprivation, fever, stress, alcohol, some medications, and sleep disorders such as obstructive sleep apnea can all increase risk.” So if you’re prone to sleepwalking, it’s important to consider outside factors that might be contributing to your 2 a.m. wander down to the kitchen. 

Sleepwalking presents a very strange vulnerability for people, one that’s stuck around precisely because, for much of human history, it didn’t need to be fixed. 

But at least we can rest assured that even with all the twitching and kicking, our pets won’t go wandering off into the night. We humans might be summoned into motion by whatever’s playing out in our sleeping brains, but our furry little buddies, snoozing blissfully through the day, seem to have a more efficient setup. They’re not going anywhere.

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

The post Why only humans sleepwalk appeared first on Popular Science.

Insects are not typically considered  food in Western society, and many would probably balk at the idea of chowing down an insect bar (though gym bros might be excited at the idea of a new low-fat source of protein). However, the participants in a recent study were actually more likely to prefer an insect protein bar over a cereal bar.  

“Insect-based food, a potential solution for the escalating global food demand, faces consumer acceptance challenges in some regions,” a team wrote in the Journal of Neuroscience, Psychology, and Economics study. “This article aims to understand the physiological reactions to an insect bar to assess its potential acceptance, thereby fostering the quest for sustainable food sources.”

Thirty-eight adults in Portugal aged between 18 and 55 took part in the study. None of them had ever tasted insect-based foods, and they began by taking a survey of their knowledge and thoughts regarding insect-based products. Next, the team measured their heart rate and brain activity with an electrocardiography (ECG) and electroencephalography (EEG) while they tried an insect protein bar and a cereal bar. 

The prediction was that the participants who had little awareness of insect-based foods would have a stronger physical response to the insect protein bar, and prefer the cereal bar. The researchers informed some of the participants which bar was which, though they told others that the insect bar was the cereal bar. 

Heart rate and brain activity revealed that participants started paying more attention and became more engaged as they ate the insect protein bar. Heart activity also increased during the tasting, and the team read this as evidence of increased arousal and attentiveness. Interestingly, these dynamics also occurred for participants who weren’t aware that they were snacking on an insect protein bar, indicating that there was more behind the reaction than just presumptions about eating insects. 

Perhaps most shocking of all, however, is that when the researchers asked the participants which food they preferred, they were overall more likely to pick the insect protein bar. That’s despite the fact that, before trying them, the participants had frequently voiced doubts or surprise when speaking about insect-based foods. 

“The findings were very surprising,” Andreia Ferreira, lead author of the study and a PhD candidate at the University of Beira Interior, said in a statement. “This was really an unexpected result as literature said to us that consumers tend to reject these novel foods. The results show us the relevance of tasting experiments on promoting this new alternative.”  

Furthermore, the “results highlight the need for improved communication about insect-based food and its advantages, given limited awareness,” the researchers wrote. “Still, when people are informed about it, they are more likely to accept it.”

The participants represent a relatively small sample size, among other limitations to the study, and additional research is necessary, according to the researchers. Still, the results confirm the rather basic notion that people might change their minds about unfamiliar foods after trying them. In other words, “don’t knock it till you try it.”

The post You may actually like eating bugs appeared first on Popular Science.