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In the quest to measure the fundamental constant that governs the strength of gravity, scientists are getting a wiggle on.

Using a pair of meter-long, vibrating metal beams, scientists have made a new measurement of “Big G,” also known as Newton’s gravitational constant, researchers report July 11 in Nature Physics. The technique could help physicists get a better handle on the poorly measured constant.

Big G is notoriously difficult to determine (SN: 9/12/13). Previous estimates of the constant disagree with one another, leaving scientists in a muddle over its true value. It is the least precisely known of the fundamental constants, a group of numbers that commonly show up in equations, making them a prime target for precise measurements.
Because the vibrating beam test is a new type of experiment, “it might help to understand what’s really going on,” says engineer and physicist Jürg Dual of ETH Zurich.

The researchers repeatedly bent one of the beams back and forth and used lasers to measure how the second beam responded to the first beam’s varying gravitational pull. To help maintain a stable temperature and avoid external vibrations that could stymie the experiment, the researchers performed their work 80 meters underground, in what was once a military fortress in the Swiss Alps.

Big G, according to the new measurement, is approximately 6.82 x 10-11 meters cubed per kilogram per square second. But the estimate has an uncertainty of about 1.6 percent, which is large compared to other measurements (SN: 8/29/18). So the number is not yet precise enough to sway the debate over Big G’s value. But the team now plans to improve their measurement, for example by adding a modified version of the test with rotating bars. That might help cut down on Big G’s wiggle room.

No beast on Earth is tougher than the tiny tardigrade. It can survive being frozen at -272° Celsius, being exposed to the vacuum of outer space and even being blasted with 500 times the dose of X-rays that would kill a human.

In other words, the creature can endure conditions that don’t even exist on Earth. This otherworldly resilience, combined with their endearing looks, has made tardigrades a favorite of animal lovers. But beyond that, researchers are looking to the microscopic animals, about the size of a dust mite, to learn how to prepare humans and crops to handle the rigors of space travel.
The tardigrade’s indestructibility stems from its adaptations to its environment — which may seem surprising, since it lives in seemingly cushy places, like the cool, wet clumps of moss that dot a garden wall. In homage to such habitats, along with a pudgy appearance, some people call tardigrades water bears or, adorably, moss piglets.

But it turns out that a tardigrade’s damp, mossy home can dry out many times each year. Drying is pretty catastrophic for most living things. It damages cells in some of the same ways that freezing, vacuum and radiation do.

For one thing, drying leads to high levels of peroxides and other reactive oxygen species. These toxic molecules chisel a cell’s DNA into short fragments — just as radiation does. Drying also causes cell membranes to wrinkle and crack. And it can lead delicate proteins to unfold, rendering them as useless as crumpled paper airplanes. Tardigrades have evolved special strategies for dealing with these kinds of damage.
As a tardigrade dries out, its cells gush out several strange proteins that are unlike anything found in other animals. In water, the proteins are floppy and shapeless. But as water disappears, the proteins self-assemble into long, crisscrossing fibers that fill the cell’s interior. Like Styrofoam packing peanuts, the fibers support the cell’s membranes and proteins, preventing them from breaking or unfolding.

At least two species of tardigrade also produce another protein found in no other animal on Earth. This protein, dubbed Dsup, short for “damage suppressor,” binds to DNA and may physically shield it from reactive forms of oxygen.

Emulating tardigrades could one day help humans colonize outer space. Food crops, yeast and insects could be engineered to produce tardigrade proteins, allowing these organisms to grow more efficiently on spacecraft where levels of radiation are elevated compared with on Earth.

Scientists have already inserted the gene for the Dsup protein into human cells in the lab. Many of those modified cells survived levels of X-rays or peroxide chemicals that kill ordinary cells (SN: 11/9/19, p. 13). And when inserted into tobacco plants — an experimental model for food crops — the gene for Dsup seemed to protect the plants from exposure to a DNA-damaging chemical called ethyl methanesulfonate. Plants with the extra gene grew more quickly than those without it. Plants with Dsup also incurred less DNA damage when exposed to ultraviolet radiation.
Tardigrades’ “packing peanut” proteins show early signs of being protective for humans. When modified to produce those proteins, human cells became resistant to camptothecin, a cell-killing chemotherapy agent, researchers reported in the March 18 ACS Synthetic Biology. The tardigrade proteins did this by inhibiting apoptosis, a cellular self-destruct program that is often triggered by exposure to harmful chemicals or radiation.

So if humans ever succeed in reaching the stars, they may accomplish this feat, in part, by standing on the shoulders of the tiny eight-legged endurance specialists in your backyard.

Modern mammals are known for their big brains. But new analyses of mammal skulls from creatures that lived shortly after the dinosaur mass extinction show that those brains weren’t always a foregone conclusion. For at least 10 million years after the dinosaurs disappeared, mammals got a lot brawnier but not brainier, researchers report in the April 1 Science.

That bucks conventional wisdom, to put it mildly. “I thought, it’s not possible, there must be something that I did wrong,” says Ornella Bertrand, a mammal paleontologist at the University of Edinburgh. “It really threw me off. How am I going to explain that they were not smart?”

Modern mammals have the largest brains in the animal kingdom relative to their body size. How and when that brain evolution happened is a mystery. One idea has been that the disappearance of all nonbird dinosaurs following an asteroid impact at the end of the Mesozoic Era 66 million years ago left a vacuum for mammals to fill (SN: 1/25/17). Recent discoveries of fossils dating to the Paleocene — the immediately post-extinction epoch spanning 66 million to 56 million years ago — does reveal a flourishing menagerie of weird and wonderful mammal species, many much bigger than their Mesozoic predecessors (SN: 10/24/19). It was the dawn of the Age of Mammals.
Before those fossil finds, the prevailing wisdom was that in the wake of the mass dino extinction, mammals’ brains most likely grew apace with their bodies, everything increasing together like an expanding balloon, Bertrand says. But those discoveries of Paleocene fossil troves in Colorado and New Mexico, as well as reexaminations of fossils previously found in France, are now unraveling that story, by offering scientists the chance to actually measure the size of mammals’ brains over time.

Bertrand and her colleagues used CT scanning to create 3-D images of the skulls of different types of ancient mammals from both before and after the extinction event. Those specimens included mammals from 17 groups dating to the Paleocene and 17 to the Eocene, the epoch that spanned 56 million to 34 million years ago.

What the team found was a shock: Relative to their body sizes, Paleocene mammal brains were relatively smaller than those of Mesozoic mammals. It wasn’t until the Eocene that mammal brains began to grow, particularly in certain sensory regions, the team reports.

To assess how the sizes and shapes of those sensory regions also changed over time, Bertrand looked for the edges of different parts of the brains within the 3-D skull models, tracing them like a sculptor working with clay. The size of mammals’ olfactory bulbs, responsible for sense of smell, didn’t change over time, the researchers found — and that makes sense, because even Mesozoic mammals were good sniffers, she says.

The really big brain changes were to come in the neocortex, which is responsible for visual processing, memory and motor control, among other skills. But those kinds of changes are metabolically costly, Bertrand says. “To have a big brain, you need to sleep and eat, and if you don’t do that you get cranky, and your brain just doesn’t function.”
So, the team proposes, as the world shook off the dust of the mass extinction, brawn was the priority for mammals, helping them swiftly spread out into newly available ecological niches. But after 10 million years or so, the metabolic calculations had changed, and competition within those niches was ramping up. As a result, mammals began to develop new sets of skills that could help them snag hard-to-reach fruit from a branch, escape a predator or catch prey.

Other factors — such as social behavior or parental care — have been important to the overall evolution of mammals’ big brains. But these new finds suggest that, at least at the dawn of the Age of Mammals, ecology — and competition between species — gave a big push to brain evolution, wrote biologist Felisa Smith of the University of New Mexico in Albuquerque in a commentary in the same issue of Science.
“An exciting aspect of these findings is that they raise a new question: Why did large brains evolve independently and concurrently in many mammal groups?” says evolutionary biologist David Grossnickle of the University of Washington in Seattle.

Most modern mammals have relatively large brains, so studies that examine only modern species might conclude that large brains evolved once in mammal ancestors, Grossnickle says. But what this study uncovered is a “much more interesting and nuanced story,” that these brains evolved separately in many different groups, he says. And that shows just how important fossils can be to stitching together an accurate tapestry of evolutionary history.

Researchers have finally deciphered a complete human genetic instruction book from cover to cover.

The completion of the human genome has been announced a couple of times in the past, but those were actually incomplete drafts. “We really mean it this time,” says Evan Eichler, a human geneticist and Howard Hughes Medical Institute investigator at the University of Washington in Seattle.

The completed genome is presented in a series of papers published online March 31 in Science and Nature Methods.

An international team of researchers, including Eichler, used new DNA sequencing technology to untangle repetitive stretches of DNA that were redacted from an earlier version of the genome, widely used as a reference for guiding biomedical research.

Deciphering those tricky stretches adds about 200 million DNA bases, about 8 percent of the genome, to the instruction book, researchers report in Science. That’s essentially an entire chapter. And it’s a juicy one, containing the first-ever looks at the short arms of some chromosomes, long-lost genes and important parts of chromosomes called centromeres — where machinery responsible for divvying up DNA grips the chromosome.

“Some of the regions that were missing actually turn out to be the most interesting,” says Rajiv McCoy, a human geneticist at Johns Hopkins University, who was part of the team known as the Telomere-to-Telomere (T2T) Consortium assembling the complete genome. “It’s exciting because we get to take the first look inside these regions and see what we can find.” Telomeres are repetitive stretches of DNA found at the ends of chromosomes. Like aglets on shoelaces, they may help keep chromosomes from unraveling.

Data from the effort are already available for other researchers to explore. And some, like geneticist Ting Wang of Washington University School of Medicine in St. Louis, have already delved in. “Having a complete genome reference definitely improves biomedical studies.… It’s an extremely useful resource,” he says. “There’s no question that this is an important achievement.”

But, Wang says, “the human genome isn’t quite complete yet.”

To understand why and what this new volume of the human genetic encyclopedia tells us, here’s a closer look at the milestone.
What did the researchers do?
Eichler is careful to point out that “this is the completion of a human genome. There is no such thing as the human genome.” Any two people will have large portions of their genomes that range from very similar to virtually identical and “smaller portions that are wildly different.” A reference genome can help researchers see where people differ, which can point to genes that may be involved in diseases. Having a view of the entire genome, with no gaps or hidden DNA, may give scientists a better understanding of human health, disease and evolution.

The newly complete genome doesn’t have gaps like the previous human reference genome. But it still has limitations, Wang says. The old reference genome is a conglomerate of more than 60 people’s DNA (SN: 3/4/21). “Not a single individual, or single cell on this planet, has that genome.” That goes for the new, complete genome, too. “It’s a quote-unquote fake genome,” says Wang, who was not involved with the project.

The new genome doesn’t come from a person either. It’s the genome of a complete hydatidiform mole, a sort of tumor that arises when a sperm fertilizes an empty egg and the father’s chromosomes are duplicated. The researchers chose to decipher the complete genome from a cell line called CHM13 made from one of these unusual tumors.

That decision was made for a technical reason, says geneticist Karen Miga of the University of California, Santa Cruz. Usually, people get one set of chromosomes from their mother and another set from their father. So “we all have two genomes in every cell.”

If putting together a genome is like assembling a puzzle, “you essentially have two puzzles in the same box that look very similar to each other,” says Miga, borrowing an analogy from a colleague. Researchers would have to sort the two puzzles before piecing them together. “Genomes from hydatidiform moles don’t present that same challenge. It’s just one puzzle in the box.”

The researchers did have to add the Y chromosome from another person, because the sperm that created the hydatidiform mole carried an X chromosome.

Even putting one puzzle together is a Herculean task. But new technologies that allow researchers to put DNA bases — represented by the letters A, T, C and G — in order, can spit out stretches up to more than 100,000 bases long. Just as children’s puzzles are easier to solve because of larger and fewer pieces, these “long reads” made assembling the bits of the genome easier, especially in repetitive parts where just a few bases might distinguish one copy from another. The bigger pieces also allowed researchers to correct some mistakes in the old reference genome.

What did they find?
For starters, the newly deciphered DNA contains the short arms of chromosomes 13, 14, 15, 21 and 22. These “acrocentric chromosomes” don’t resemble nice, neat X’s the way the rest of the chromosomes do. Instead, they have a set of long arms and one of nubby short arms.

The length of the short arms belies their importance. These arms are home to rDNA genes, which encode rRNAs, which are key components of complex molecular machines called ribosomes. Ribosomes read genetic instructions and build all the proteins needed to make cells and bodies work. There are hundreds of copies of these rDNA regions in every person’s genome, an average of 315, but some people have more and some fewer. They’re important for making sure cells have protein-building factories at the ready.

“We didn’t know what to expect in these regions,” Miga says. “We found that every acrocentric chromosome, and every rDNA on that acrocentric chromosome, had variants, changes to the repeat unit that was private to that particular chromosome.”

By using fluorescent tags, Eichler and colleagues discovered that repetitive DNA next to the rDNA regions — and perhaps the rDNA too — sometimes switches places to land on another chromosome, the team reports in Science. “It’s like musical chairs,” he says. Why and how that happens is still a mystery.

The complete genome also contains 3,604 genes, including 140 that encode proteins, that weren’t present in the old, incomplete genome. Many of those genes are slightly different copies of previously known genes, including some that have been implicated in brain evolution and development, autism, immune responses, cancer and cardiovascular disease. Having a map of where all these genes lie may lead to a better understanding of what they do, and perhaps even of what makes humans human.

One of the biggest finds may be the structure of all of the human centromeres. Centromeres, the pinched portions which give most chromosomes their characteristic X shape, are the assembly points for kinetochores, the cellular machinery that divvies up DNA during cell division. That’s one of the most important jobs in a cell. When it goes wrong, birth defects, cancer or death can result. Researchers had already deciphered the centromeres of fruit flies and the human 8, X and Y chromosomes (SN: 5/17/19), but this is the first time that researchers got a glimpse of the rest of the human centromeres.

The structures are mostly head-to-tail repeats of about 171 base pairs of DNA known as alpha satellites. But those repeats are nestled within other repeats, creating complex patterns that distinguish each chromosome’s individual centromere, Miga and colleagues describe in Science. Knowing the structures will help researchers learn more about how chromosomes are divvied up and what sometimes throws off the process.
Researchers also now have a more complete map of epigenetic marks — chemical tags on DNA or associated proteins that may change how genes are regulated. One type of epigenetic mark, known as DNA methylation, is fairly abundant across the centromeres, except for one spot in each chromosome called the centromeric dip region, Winston Timp, a biomedical engineer at Johns Hopkins University and colleagues report in Science.

Those dips are where kinetochores grab the DNA, the researchers discovered. But it’s not yet clear whether the dip in methylation causes the cellular machinery to assemble in that spot or if assembly of the machinery leads to lower levels of methylation.

Examining DNA methylation patterns in multiple people’s DNA and comparing them with the new reference revealed that the dips occur at different spots in each person’s centromeres, though the consequences of that aren’t known.

About half of genes implicated in the evolution of humans’ large, wrinkly brains are found in multiple copies in the newly uncovered repetitive parts of the genome (SN: 2/26/15). Overlaying the epigenetic maps on the reference allowed researchers to figure out which of many copies of those genes were turned on and off, says Ariel Gershman, a geneticist at Johns Hopkins University School of Medicine.

“That gives us a little bit more insight into which of them are actually important and playing a functional role in the development of the human brain,” Gershman says. “That was exciting for us, because there’s never been a reference that was accurate enough in these [repetitive] regions to tell which gene was which, and which ones are turned on or off.”

What is next?
One criticism of genetics research is that it has relied too heavily on DNA from people of European descent. CHM13 also has European heritage. But researchers have used the new reference to discover new patterns of genetic diversity. Using DNA data collected from thousands of people of diverse backgrounds who participated in earlier research projects compared with the T2T reference, researchers more easily and accurately found places where people differ, McCoy and colleagues report in Science.

The Telomere-to-Telomere Consortium has now teamed up with Wang and his colleagues to make complete genomes of 350 people from diverse backgrounds (SN: 2/22/21). That effort, known as the pangenome project, is poised to reveal some of its first findings later this year, Wang says.

McCoy and Timp say that it may take some time, but eventually, researchers may switch from using the old reference genome to the more complete and accurate T2T reference. “It’s like upgrading to a new version of software,” Timp says. “Not everyone is going to want to do it right away.”

The completed human genome will also be useful for researchers studying other organisms, says Amanda Larracuente, an evolutionary geneticist at the University of Rochester in New York who was not involved in the project. “What I’m excited about is the techniques and tools this team has developed, and being able to apply those to study other species.”

Eichler and others already have plans to make complete genomes of chimpanzees, bonobos and other great apes to learn more about how humans evolved differently than apes did. “No one should see this as the end,” Eichler says, “but a transformation, not only for genomic research but for clinical medicine, though that will take years to achieve.”

A chance alignment may have revealed a star from the universe’s first billion years.

If confirmed, this star would be the most distant one ever seen, obliterating the previous record (SN: 7/11/17). Light from the star traveled for about 12.9 billion years on its journey toward Earth, about 4 billion years longer than the former record holder, researchers report in the March 30 Nature. Studying the object could help researchers learn more about the universe’s composition during that early, mysterious time.

“These are the sorts of things that you only hope you could discover,” says astronomer Katherine Whitaker of the University of Massachusetts Amherst, who was not part of the new study.
The researchers found the object while analyzing Hubble Space Telescope images of dozens of clusters of galaxies nearer to Earth. These clusters are so massive that they bend and focus the light from more distant background objects, what’s known as gravitational lensing (SN: 10/6/15).

In images of one cluster, astronomer Brian Welch of Johns Hopkins University and colleagues noticed a long, thin, red arc. The team realized that the arc was a background galaxy whose light the cluster had warped and amplified.

Atop that red arc is a bright spot that is too small to be a small galaxy or a star cluster, the researchers say. “We stumbled into finding that this was a lensed star,” Welch says.

The researchers estimate that the star’s light originates from only 900 million years after the Big Bang, which took place about 13.8 billion years ago.

Welch and his colleagues think that the object, which they poetically nicknamed “Earendel” from the old English word meaning “morning star” or “rising light,” is a behemoth with at least 50 times the mass of the sun. But the researchers can’t pin down that value, or learn more about the star or even confirm that it is a star, without more detailed observations.

The researchers plan to use the recently launched James Webb Space Telescope to examine Earendel (SN: 10/6/21). The telescope, also known as JWST, will begin studying the distant universe this summer.

JWST may uncover objects from even earlier times in the universe’s history than what Hubble can see because the new telescope will be sensitive to light from more distant objects. Welch hopes that the telescope will find many more of these gravitationally lensed stars. “I’m hoping that this record won’t last very long.”

Western banded geckos don’t look like they’d win in a fight. Yet this unassuming predator dines on venomous scorpions, and a field study published in the March Biological Journal of the Linnean Society shows how the lizards take down such perilous prey.

Geckos bite the scorpion and thrash their heads and upper bodies back and forth, body-slamming the scorpion against the ground, new high-speed video reveals. “The behavior is so fast that you can’t see what’s actually happening,” says San Diego State University biologist Rulon Clark. “[You] see the gecko lunge and then see this crazy blur of motion … like trying to watch the wings of a hummingbird.”

Clark first noticed the behavior in the 1990s, during undergraduate fieldwork in the Sonoran Desert near Yuma, Ariz. When he returned with colleagues to study kangaroo rats and rattlesnakes, the team filmed geckos as well. The researchers captured western banded geckos (Coleonyx variegatus) and dune scorpions (Smeringurus mesaensis) in the desert at night (along with harmless arthropods, like field crickets and sand roaches, to compare), and documented the showdowns.
Normal gecko feeding behavior usually involves lunging out, grabbing prey with their mouth, and chomping it, says Clark. With scorpions, it’s totally different after the initial lunge. Such shake feeding is a known method for carnivores and adventurous eaters. For instance, dolphins shake (and toss) octopuses before eating (SN: 4/25/17).

The fact that this delicate, cold-blooded species not known for speed can achieve such physical gyrations is impressive, Clark says. Songbirds called loggerhead shrikes whip larger predators in circles (SN: 9/7/18), but at a lower frequency (11 hertz compared to 14 Hz in geckos). Whiptail lizards also violently shake scorpions, but at unknown speeds. The closest documented match to the speed of gecko shake feeding is small mammals shaking themselves dry; guinea pigs clock in at around 14 Hz, as well.

It’s unclear how common this behavior is among geckos. And aside from generally subduing a venomous foe, how it works — killing the scorpion, immobilizing it, damaging its stinger, or reducing how much venom gets injected — remains a mystery.

Four billion years ago, lava spilled onto the moon’s crust, etching the man in the moon we see today. But the volcanoes may have also left a much colder legacy: ice.

Two billion years of volcanic eruptions on the moon may have led to the creation of many short-lived atmospheres, which contained water vapor, a new study suggests. That vapor could have been transported through the atmosphere before settling as ice at the poles, researchers report in the May Planetary Science Journal.
Since the existence of lunar ice was confirmed in 2009, scientists have debated the possible origins of water on the moon, which include asteroids, comets or electrically charged atoms carried by the solar wind (SN: 11/13/09). Or, possibly, the water originated on the moon itself, as vapor belched by the rash of volcanic eruptions from 4 billion to 2 billion years ago.

“It’s a really interesting question how those volatiles [such as water] got there,” says Andrew Wilcoski, a planetary scientist at the University of Colorado Boulder. “We still don’t really have a good handle on how much are there and where exactly they are.”

Wilcoski and his colleagues decided to start by tackling volcanism’s viability as a lunar ice source. During the heyday of lunar volcanism, eruptions happened about once every 22,000 years. Assuming that H2O constituted about a third of volcano-spit gasses — based on samples of ancient lunar magma — the researchers calculate that the eruptions released upward of 20 quadrillion kilograms of water vapor in total, or the volume of approximately 25 Lake Superiors.

Some of this vapor would have been lost to space, as sunlight broke down water molecules or the solar wind blew the molecules off the moon. But at the frigid poles, some could have stuck to the surface as ice.

For that to happen, though, the rate at which the water vapor condensed into ice would have needed to surpass the rate at which the vapor escaped the moon. The team used a computer simulation to calculate and compare these rates. The simulation accounted for factors such as surface temperature, gas pressure and the loss of some vapor to mere frost.

About 40 percent of the total erupted water vapor could have accumulated as ice, with most of that ice at the poles, the team found. Over billions of years, some of that ice would have converted back to vapor and escaped to space. The team’s simulation predicts the amount and distribution of ice that remains. And it’s no small amount: Deposits could reach hundreds of meters at their thickest point, with the south pole being about twice as icy as the north pole.

The results align with a long-standing assumption that ice dominates at the poles because it gets stuck in cold traps that are so cold that ice will stay frozen for billions of years.
“There are some places at the lunar poles that are as cold as Pluto,” says planetary scientist Margaret Landis of the University of Colorado Boulder.

Volcanically sourced water vapor traveling to the poles, though, probably depends on the presence of an atmosphere, say Landis, Wilcoski and their colleague Paul Hayne, also a planetary scientist at the University of Colorado Boulder. An atmospheric transit system would have allowed water molecules to travel around the moon while also making it more difficult for them to flee into space. Each eruption triggered a new atmosphere, the new calculations indicate, which then lingered for about 2,500 years before disappearing until the next eruption some 20,000 years later.

This part of the story is most captivating to Parvathy Prem, a planetary scientist at Johns Hopkins Applied Physics Laboratory in Laurel, Md., who wasn’t involved in the research. “It’s a really interesting act of imagination.… How do you create atmospheres from scratch? And why do they sometimes go away?” she says. “The polar ices are one way to find out.”

If lunar ice was belched out of volcanoes as water vapor, the ice may retain a memory of that long-ago time. Sulfur in the polar ice, for example, would indicate that it came from a volcano as opposed to, say, an asteroid. Future moon missions plan to drill for ice cores that could confirm the ice’s origin.

Looking for sulfur will be important when thinking about lunar resources. These water reserves could someday be harvested by astronauts for water or rocket fuel, the researchers say. But if all the lunar water is contaminated with sulfur, Landis says, “that’s a pretty critical thing to know if you plan on bringing a straw with you to the moon.”

Six years ago, tour guide Brenden Miles was traveling down the Kinabatangan River in the Malaysian part of Borneo, when he spotted an odd-looking primate he had never seen before. He snapped a few pictures of the strange monkey and, on reaching home, checked his images.

“At first, I thought it could be a morph of the silvered leaf monkey,” meaning a member of the species with rare color variation, Miles says. But then he noticed other little details. “Its nose was long like that of a proboscis monkey, and its tail was thicker than that of a silvered leaf [monkey],” he says. He posted a picture of the animal on Facebook and forgot all about it.

Now, an analysis of that photo and others suggests that the “mystery monkey” is a hybrid of two distantly related primate species that share the same fragmented habitat.
The putative offspring was produced when a male proboscis monkey (Nasalis larvatus) mated with a female silvered leaf monkey (Trachypithecus cristatus), researchers suggest April 26 in the International Journal of Primatology. And that conclusion has the scientists worried about the creature’s parent species.

Hybridization between closely related organisms has been observed in captivity and occasionally in the wild (SN: 7/23/21). “But hybridization across genera, that’s very rare,” says conservation practitioner Ramesh Boonratana, the regional vice-chair for Southeast Asia for the International Union for Conservation of Nature’s primate specialist group.

Severe habitat loss, fragmentation and degradation caused by expanding palm oil plantations along the Kinabatangan River could explain how the possible hybrid came to be, says primatologist Nadine Ruppert.

“Different species — even from the same genus — when they share a habitat, they may interact with each other, but they may usually not mate. This kind of cross-genera hybridization happens only when there is some ecological pressure,” says Ruppert, of the Universiti Sains Malaysia in Penang Island.

The state of Sabah, where Kinabatangan River is located, lost about 40 percent of its forest cover from 1973 to 2010, with logging and palm oil plantations being the main drivers of deforestation, a study in 2014 found.
“In certain areas, both [monkey] species are confined to small forest fragments along the river,” Ruppert says. This leads to competition for food, mates and other resources. “The animals cannot disperse and, in this case, the male of the larger species — the proboscis monkey — can easily displace the male silvered leaf monkey.”

Since 2016, there have been some more documented sightings of the mystery monkey, though these have been sporadic. The infrequent sightings and the COVID-19 pandemic has, for now, prevented researchers from gathering fecal samples for genetic analysis to reveal the monkey’s identity. Instead, Ruppert and colleagues compared images of the possible hybrid with those of the parent species, both visually as well as by using limb ratios. “If the individual was from one of the two parent species, all its measurements would be similar to that of one species,” Ruppert says. “But that is not the case with this animal.”

A photograph of a male proboscis monkey mating with a female silvered leaf monkey, along with anecdotes from boat operators and tour guides about a single male proboscis monkey hanging around a troop of female silvered leaf monkeys, has added further weight to the researchers’ conclusion.

The mystery monkey is generating a lot of excitement in the area, but Ruppert is concerned for the welfare of both proposed parent species. The International Union for Conservation of Nature classifies proboscis monkeys as endangered and silvered leaf monkeys as vulnerable. “The hybrid is gorgeous, but we don’t want to see more of them,” Ruppert says. “Both species should have a large enough habitat, dispersal opportunities and enough food to conduct their natural behaviors in the long term.”

Increasing habitat loss or fragmentation in Borneo and elsewhere as a result of changing land uses or climate change could lead to more instances of mating — or at least, attempts at mating — between species or even genera, Boonratana says.

The mystery monkey was last photographed in September of 2020 with swollen breasts and holding a baby, suggesting that the animal is a fertile female. That’s another surprising development, the researchers say, because most hybrids tend to be sterile.

The pandemic has entered a murky stage, and social norms are quickly shifting, something I’ve thought a lot about lately. Many people are testing at home, or not at all. Here in Vermont, where I live, you can pick up a type of PCR test that can be taken at home. But state officials both here and elsewhere are no longer carefully monitoring the results of these tests, which means that the actual spread of coronavirus in the U.S. population remains unclear (SN: 4/22/22).

For a few weeks, rumors of a stealth COVID-19 wave have been circulating both in the media and on my Twitter feed. Now cases and hospitalizations are rising, as are the levels of coronavirus in wastewater. That suggests that more cases, and ultimately deaths, could follow.
Even with rising caseloads and a vaccination rate that has flatlined at about 66 percent of the eligible population, the American public has largely begun to move on from the COVID-19 crisis. People are shedding their masks, eating out, attending concerts, traveling to far-flung locations, having large, indoor weddings and doing all the social things that people tend to do when left to their own devices.

The 2,600-person White House Correspondents’ Association dinner late last month is a case in point. Just as host Trevor Noah prophesied, many of those in attendance have since tested positive for COVID-19, including U.S. Secretary of State Antony Blinken and reporters from NBC, ABC, the Washington Post, Politico and other media outlets. And those who almost certainly knew better — cue White House Coronavirus Response Coordinator Ashish Jha — nonetheless made an appearance.

Myriad quirks related to human behavior undoubtedly underpin these arguably poor choices. The Decision Lab website has a list of the biases and mental shortcuts people use to make decisions. The one that caught my eye is social norms. This particular quirk outlines what behaviors people deem appropriate in a given situation.

I started thinking about social norms while writing a feature on how to get people in the United States to eat less meat when the practice is so, well, normal (SN: 5/11/22). Social norms, my research informed me, vary with the group one is hanging out with and one’s environs. “We rapidly switch our perspective depending on the context of the situation we find ourselves in,” writes marketing expert John Laurence on the Decision Lab site.

I might have found this idea of rapid switching suspect had I not recently experienced the phenomenon. My husband’s Disney-phile brother and his wife had been planning a family reunion in Disney World in Florida since the start of the pandemic. And I, a curmudgeonly sort not prone to feeling the magic, long ago agreed to go on the condition that other people do all the planning. And so it was, after multiple COVID-related postponements, that my kids, my husband and I landed in Orlando on a blisteringly hot April day.

Disney normal, I soon learned, bore little resemblance to Vermont normal. This was obvious immediately from people’s attire. All around me parents and kids dressed in coordinated outfits and matching Mickey Mouse ears. (Apologies to my kids — your mom missed the fashion memo.)
Social norms almost certainly arose to foster cohesion among our earliest ancestors, who needed solidarity to hunt large prey, share limited resources and ward off predators and enemy tribes. In-group norms also provide humans with a sense of belonging, which research suggests is vital for our overall health. A meta-analysis of more than 3.4 million people followed for an average of seven years showed that the likelihood of dying during the study period increased by 26 percent for participants who reported feeling alone (SN: 3/29/20).

Not surprisingly, then, one of the strongest drivers of human behavior is to seek out belonging. At Disney, that quest means blocking out the reality that exists just outside the fiefdom. Wars, climate crises, political fighting and the like have no place within those magical walls. Nor do reminders of a global health crisis that, according to the latest World Health Organization estimates, has thus far killed nearly 15 million people worldwide.

Within Disney’s walls, throngs of mostly maskless tourists packed onto iconic rides and into restaurants. When halfway through our trip, a Florida judge ruled that masks could not be mandated on public transit, nary a mask was to be seen on buses shuttling people to the Magic Kingdom and Epcot Center. And everywhere, all the time, people seemed to be coughing, sniffling or blowing their noses.

As a science reporter covering COVID-19, I certainly knew that I should keep my mask on. And yet, my resolve soon faltered. My kids pointed out that no one else was masking, not even my typically rule-following relatives. Donning my mask meant confessing that I was not reveling in the sparkle and glitz and magic and making all too obvious to my beloved extended family that I did not, in fact, belong. I kept my face covering in my pocket.

Humans’ tendency toward conformity is not all bad. In a now classic study from the 1980s, researchers investigated how to reduce water consumption in drought-prone California. Signs at the University of California, Santa Cruz asking students to turn off the shower while soaping up led to only 6 percent compliance. So researchers recruited male students to serve as norm-setting role models. These role models would hang out in the communal shower until they heard another student come in, and then soap up with the water off. When one role model soaped with the shower off, roughly half of the unwitting students also began turning off their faucets at soaping time. Compliance jumped to 67 percent when two role models followed the sign.

But conformity can also distort how we make decisions. For instance, in the summer of 2020, when the pandemic was still new, researchers asked 23,000 people in Mexico to predict how a fictional woman named Mariana would decide whether or not to attend a birthday party. Most participants believed Mariana should not attend. But when they read a sentence suggesting her friends would attend or that others approved of the party, their predictions that Mariana would also go increased by 25 percent, researchers reported in PLOS ONE.

My decision to conform to Disney normal ended predictably — with a positive COVID-19 test. After weeks of coughing and sleepless nights, though, my frustration is less directed at myself than at political leaders who so blithely ignore both epidemiology and human behavior research and tell us to live like it’s 2019. It’s not. Nor is it 2020 or 2021. It’s the murky year known as 2022. And the rules of behavior that bolster our social norms — such as role models who refrain from large, indoor, unmasked gatherings, and leaders who uphold mask mandates on public transit to protect the most vulnerable — should reflect this liminal space.

A speck of gold dancing to a pipe organ’s tune has helped solve a long-standing mystery: why certain wind instruments violate a mathematical formula that should describe their sound.

In 1860, physicist Hermann von Helmholtz — famous for his law of the conservation of energy — devised an equation relating the wavelength of a pipe’s fundamental tone (the lowest frequency at which it resonates) to pipe length (SN: 3/31/28). Generally, the longer a pipe is, the lower its fundamental tone will be.

But the equation doesn’t work in practice. A pipe’s fundamental tone always sounds lower than the pipe’s length suggests it should according to Helmholtz’s formula. Fixing this problem requires adding an “end correction” to the equation. In the case of open-ended pipes such as flutes and those of organs, the end correction is 0.6 times the radius of the pipe. Why this was, nobody could figure out.

A break in the case came in 2010. Instrument builder and restorer Bernhardt Edskes of Wohlen, Switzerland was tuning an organ when he spotted a piece of gold that had come loose from a pipe’s gilded lip. Air pumping through the pipe should have carried away the gold. Instead, it seemed to be trapped in a vortex just above the pipe’s upper rim.

Edskes told his friend, physicist Leo van Hemmen of the Technical University of Munich, about the observation. Together with colleagues from Munich and Wageningen University in the Netherlands, they studied how air moves through playing organ pipes using cigarette smoke.

When an organ pipe sounds, a vortex indeed forms over the pipe’s rim, the team reported March 14 in Chicago at a meeting of the American Physical Society. What’s more, this vortex is capped by a hemisphere of resonating air.
This vibrating air cap, van Hemmen says, is the long-sought explanation for the “end correction.” The cap effectively lengthens the organ pipe by the exact amount that must be tacked on to Helmholtz’s formula to explain the pipe’s fundamental tone.