People pay deerly for the switch from daylight saving time.

The change to standard time in autumn corresponds with an average 16 percent increase in deer-vehicle collisions in the United States, scientists report November 2 in Current Biology. The researchers estimate that eliminating the switch could save nearly 37,000 deer — and 33 human lives.

In a typical year, there are more than 2 million deer-vehicle collisions — about 7 percent of total vehicle crashes. To see how much the biannual time change impacts those numbers, wildlife biologist Laura Prugh and colleagues compiled data from 23 states that tracked whether a crash involved an animal and what time the crash occurred. The team compared those numbers to traffic volumes for each state between 2013 and 2019, focusing on the weeks before and after the switches to daylight saving time in springtime and back to standard time come fall.

Springing forward had little effect, but almost 10 percent of yearly deer collisions on average took place around the autumn fallback — when the bulk of human traffic shifted to after dark. The problem was especially acute on the East Coast. “You see [a] really steep spike in the fall,” says Prugh, of the University of Washington in Seattle. “In the western states, you also see an increase, but it’s not nearly as sharp.” On the East Coast, the autumn switch falls in the middle of mating season for white-tailed deer. Not only are more drivers active after dark, more deer are too. “The timing could not be worse.”

Eliminating the clock change wouldn’t completely wipe out the spike in crashes — mating season plays a big role, regardless of what time sunset happens. But the scientists estimate that keeping daylight saving time year-round would decrease total deer-human collisions by about 2 percent — saving dozens of people, thousands of human injuries and tens of thousands of deer. It’s another reason for us all to move toward the light (SN: 3/31/14).

The monument consisted of a circle of immense, finely tooled stone archways surrounded by a range of 56 equally spaced [holes].… The precisely proportioned placement of the stones and holes has led archaeologists to presume that the monument had some great astrological significance.… As an alternate explanation, the researchers say perhaps there were 56 families, clans or social units who built Stonehenge and who were entitled to dig one of the [holes] and use it to inter cremated remains.

Update
Stonehenge’s purpose remains murky, but the monument’s origin is becoming clearer thanks to science. For at least the first 500 years of its existence, Stonehenge was a cemetery (SN: 5/29/08). A chemical analysis of remains at the site suggests that some of the people interred there came from Wales, more than 200 kilometers west of where Stonehenge stands in southern England (SN: 8/2/18). The monument’s first building blocks also may have come from Wales, repurposed from a stone circle there, but that hypothesis is debated (SN: 2/11/21).

An ancient, armored worm may be the key to unraveling the evolutionary history of a diverse collection of marine invertebrates.

Discovered in China, a roughly 520-million-year-old fossil of the newly identified worm, dubbed Wufengella, might be the missing link between three of the phyla that constitute a cadre of sea creatures called lophophorates.

Based on a genetic analysis, Wufengella is probably the common ancestor that connects brachiopods, bryozoans and phoronid worms, paleontologist Jakob Vinther and colleagues report September 27 in Current Biology.

“We had been speculating that [the common ancestor] may have been some wormy animal that had plates on its back,” says Vinther, of the University of Bristol in England. “But we never had the animal.”

Roughly half a billion years ago, nearly all major animal groups burst onto the scene in a flurry of evolutionary diversification during what’s known as the Cambrian explosion (SN: 4/24/19). During this time, lophophorates experienced a rapid growth of species, which has obscured the group’s evolutionary history.
One thing that ties together the different phyla of the group is their tentacle-like feeding tubes known as lophophores. But beyond that commonality, the phyla are all quite different. Brachiopods are shelled animals that at first glance resemble clams. Bryozoans — commonly known as moss animals — are microscopic sedentary critters that live in corallike colonies. And phoronids, or horseshoe worms, are unsegmented, soft-bodied creatures that live in stationary, tubelike structures. (More recently, some researchers have determined that hyoliths — an extinct animal known by their conical shells (SN: 1/11/17) — are also lophophorates because of the tentacled organ that surrounds their mouth.)

Wufengella doesn’t belong to any of these phyla, Vinther and his colleagues found. But the critter has characteristics similar to those of brachiopods, horseshoe worms or bryozoans: a series of asymmetric, armored back plates, a wormlike body and bristles that stick out from lobes surrounding its body.
The fossil is a “great find,” says Gonzalo Giribet, an invertebrate zoologist at Harvard University who was not involved in the research. Still, the scientists’ analysis does not confirm that Wufengella is the long-sought missing link, he cautions, but rather suggests it.

Some researchers had hypothesized that lophophorates’ common ancestor would be a stationary creature that sat on the seafloor and fed only through tubes, similar to its modern kin. The Wufengella fossil could refute this idea; the animal’s body plan suggests instead that it crawled around, the researchers say.

A fossil like Wufengella had long been high on Vinther’s bucket list of fossils that he and his colleagues hoped to find. But “we always thought, ‘Well, we probably will never see that in real life,’” he says. Typically, such a creature would have spent its life in shallow water. Organisms don’t tend to preserve well there, decaying faster due to exposure to lots of oxygen. Vinther suggests that the Wufengella that his team found probably washed out to deep water in a storm.

Now that the researchers have found one Wufengella, they hope to find more, in part to see if there are other varieties. And perhaps the team could identify even more distant ancestors further back on the tree of life that might connect lophophorates with other animal groups such as mollusks, Vinther says, further fleshing out how life on Earth is connected.

Roughly 3,000 light-years from Earth sits one of the most complex and least understood nebulae, a whirling landscape of gas and dust left in the wake of a star’s death throes. A new computer visualization reveals the 3-D structure of the Cat’s Eye nebula and hints at how not one, but a pair of dying stars sculpted its complexity.

The digital reconstruction, based on images from the Hubble Space Telescope, reveals two symmetric rings around the nebula’s edges. The rings were probably formed by a spinning jet of charged gas that was launched from two stars in the nebula’s center, Ryan Clairmont and colleagues report in the October Monthly Notices of the Royal Astronomical Society.

“I realized there hasn’t been a comprehensive study of the structure of the nebula since the early ’90s,” says Clairmont, an undergraduate at Stanford University. Last year, while a high school student in San Diego, he reached out to a couple of astrophysicists at a scientific imaging company called Ilumbra who had written software to reconstruct the 3-D structure of astronomical objects.

The team combined Hubble images with ground-based observations of light in several wavelengths, which revealed the motions of the nebula’s gas. Figuring out which parts were moving toward and away from Earth helped reveal its 3-D structure.

The team identified two partial rings to either side of the nebula’s center. The rings’ symmetry and unfinished nature suggest they are the remains of a plasma jet launched from the heart of the nebula, then snuffed out before it could complete a full circle. Such jets are usually formed through an interaction between two stars orbiting one another, says Ilumbra partner Wolfgang Steffen, who is based in Kaiserslautern, Germany.

The work won Clairmont a prize at the 2021 International Science and Engineering Fair, an annual competition run by the Society for Science, which publishes Science News. Steffen was skeptical about the tight deadline — when Clairmont reached out, he had just two months to complete the project.

“I said that’s impossible! Not even Ph.D. students or anybody has tried that before,” Steffen says. “He did it brilliantly. He pulled it all off and more than we expected.”

[In the late 1960s], about the best means of cleaning up oil was to put straw on it, then scoop up the oily straw by hand or with pitchforks. Now industry … has devised an arsenal of oil cleanup chemicals. Thin-layer chemicals can be used to herd oil together and to thicken it…. Chemicals are available as absorbents too. Still other chemicals … disperse oil throughout the water. Other chemicals show promise as oil-burning agents.

Update
Chemicals are the norm today, but the future of oil-cleanup technology may well be microbial. In recent years, researchers have shown that soil microbes broke down some of the oil from the 2010 Deepwater Horizon spill in the Gulf of Mexico (SN Online: 6/26/15). And electrical bacteria, which channel electricity through their threadlike bodies, could help by turning oil munchers’ waste into fuel for the microbes, scientists reported (SN: 7/16/22 & 7/30/22, p. 24). Microbial mops aren’t yet ready for prime time, so chemical dispersants, fire and spongelike sorbents remain key tools in cleanup kits.

Body changes at the brink of adulthood can get awkward in humans, but at least our eyes don’t pop out of our heads on stalks longer than our legs.

High-rise eyes, however, give macho pizzazz to the adult male Pelmatops fruit fly. In one of the stalkier species, P. tangliangi, the eyes-up transformation takes only about 50 minutes, a new study reports. Once stretched, the skinny eyestalks darken and harden, keeping the eyes stuck out like selfie sticks for the rest of the fly’s life.
The details of P. tangliangi’s eye lift come from the first published photo sequence of their ocular blossoming, which appears in the September Annals of the Entomological Society of America. Biologists have known that eyestalks evolved in eight different fly families. Yet Pelmatops flies have gotten so little scientific attention that a lot of their basic biology has been a string of question marks.

Video images show the eyestalks curl and rise irregularly. Yet “they are not flopping around while partly inflated,” says Xiaolin Chen, an entomologist and evolutionary biologist at the Chinese Academy of Sciences in Beijing. “They seem slightly stiff, but still flexible enough.”

Females of the species may raise shorter eyestalks too — if Chen and her colleagues have found the right females. Chen suspects that what are now named as two species, based on the few specimens available, may just be two sexes of the same species. The new paper describes a male P. tangliangi mating with a female known by a different species name. Her stalks aren’t as magnificent as his, but she has some.

While the headgear can burden a flying insect, long eyestalks may give flies some swagger. These Pelmatops and other kinds of stalk-eyed flies face off, eyestalk to eyestalk, with uppity intruders. There’s no knocking and locking stalks in fierce fly disputes though. Any pushing and shoving, Chen says, is “done with other body parts.”

Extreme eyes may also have other benefits. In the wild, Chen finds these fruit flies on long stems of Rubus berry brambles. The eyes naturally periscope outward and upward, allowing the flies to spot danger while the body stays hidden in the greenery.

Engraved into the side of a nearly 4,000-year-old ivory comb is a simple wish: Get these lice out of my hair.

This faint inscription, written in the early language of the ancient Canaanites, represents the earliest known instance of a complete sentence written using a phonetic alphabet, says archaeologist Yosef Garfinkel of the Hebrew University of Jerusalem.

The writing system of the Canaanites, who lived in a region in the eastern Mediterranean called the Levant until around 2,000 years ago, later served as a major basis for many modern alphabets (SN: 7/27/17). That makes the comb “the most important object I’ve ever found during an excavation,” says Garfinkel. The research was published November 9 in the Jerusalem Journal of Archaeology.
The Canaanites were a cultural group that traded widely across the Mediterranean. Few of their written records have survived, so most of what researchers know about them come from other documents, such as the Old Testament.

The comb was the unearthed in 2016 among the ruins of the ancient city of Lachish in present-day Israel. Years later, when the comb was sent to a lab to search for traces of lice, someone noticed faint symbols etched on the side. A closer look revealed that the symbols spelled out the sentence, “May this tusk root out the lice of the hair and the beard,” Garfinkel and colleagues report November 9 in the Jerusalem Journal of Archaeology.

The discovery may offer a glimpse into the life of one of Lachish’s wealthy denizens. The fact that the sentence refers to a beard suggests it belonged to an elite man, Garfinkel says, since elephant ivory was an expensive good that had to be imported from Egypt.

The plea against lice is “so human,” says Garfinkel, who notes that other writings from the time tend to center around royal accomplishments or religion. It also appears that the comb was able to fulfill its purpose, at least somewhat. Between the teeth, the researchers found the ancient remains of a louse.

There’s a new way to rip apart harmful “forever chemicals,” scientists say.

Perfluoroalkyl and polyfluoroalkyl substances, also known as PFAS, are found in nonstick pans, water-repellent fabrics and food packaging and they are pervasive throughout the environment. They’re nicknamed forever chemicals for their ability to stick around and not break down. In part, that’s because PFAS have a super strong bond between their carbon and fluorine atoms (SN: 6/4/19). Now, using a bit of heat and two relatively common compounds, researchers have degraded one major type of forever chemical in the lab, the team reports in the Aug. 19 Science. The work could help pave the way for a process for breaking down certain forever chemicals commercially, for instance by treating wastewater.
“The fundamental knowledge of how the materials degrade is the single most important thing coming out of this study,” organic chemist William Dichtel said in an August 16 news conference.

While some scientists have found relatively simple ways of breaking down select PFAS, most degradation methods require harsh, energy-intensive processes using intense pressure — in some cases over 22 megapascals — or extremely high temperatures — sometimes upwards of 1000⁰ Celsius — to break the chemical bonds (SN: 6/3/22).

Dichtel, of Northwestern University in Evanston, Ill., and his team experimented with two substances found in nearly every chemistry lab cabinet: sodium hydroxide, also known as lye, and a solvent called dimethyl sulfoxide, or DMSO. The team worked specifically with a group of forever chemicals called PFCAs, which contain carboxylic acid and constitute a large percentage of all PFAS. Some of these kinds of forever chemicals are found in water-resistant clothes.

When the team combined PFCAs with the lye and DMSO at 120⁰ C and with no extra pressure needed, the carboxylic acid fell off the chemical and became carbon dioxide in a process called decarboxylation. What happened next was unexpected, Dichtel said. Loss of the acid led to a process causing “the entire molecule to fall apart in a cascade of complex reactions.” This cascade involved steps that degraded the rest of the chemical into fluoride ions and smaller carbon-containing products, leaving behind virtually no harmful by-products. .

“It’s a neat method, it’s different from other ones that have been tried,” says Chris Sales, an environmental engineer at Drexel University in Philadelphia who was not involved in the study. “The biggest question is, how could this be adapted and scaled up?” Northwestern has filed a provisional patent on behalf of the researchers.

Understanding this mechanism is just one step in undoing forever chemicals, Dichtel’s team said. And more research is needed: There are other classes of PFAS that require their own solutions. This process wouldn’t work to tackle PFAS out in the environment, because it requires a concentrated amount of the chemicals. But it could one day be used in wastewater treatment plants, where the pollutants could be filtered out of the water, concentrated and then broken down.

Some mosquitoes have a near-foolproof thirst for human blood. Previous attempts to prevent the insects from tracking people down by blocking part of mosquitoes’ ability to smell have failed. A new study hints it’s because the bloodsuckers have built-in workarounds to ensure they can always smell us.

For most animals, individual nerve cells in the olfactory system can detect just one type of odor. But Aedes aegypti mosquitoes’ nerve cells can each detect many smells, researchers report August 18 in Cell. That means if a cell were to lose the ability to detect one human odor, it still can pick up on other scents.
The study provides the most detailed map yet of a mosquito’s sense of smell and suggests that concealing human aromas from the insects could be more complicated than researchers thought.

Repellents that block mosquitoes from detecting human-associated scents could be especially tricky to make. “Maybe instead of trying to mask them from finding us, it would be better to find odorants that mosquitoes don’t like to smell,” says Anandasankar Ray, a neuroscientist at the University of California, Riverside who was not involved in the work. Such repellents may confuse or irritate the bloodsuckers and send them flying away (SN: 9/21/11; SN: 3/4/21).

Effective repellents are a key tool to prevent mosquitoes from transmitting disease-causing viruses such as dengue and Zika (SN: 7/11/22). “Mosquitoes are responsible for more human deaths than any other creature,” says Olivia Goldman, a neurobiologist at Rockefeller University in New York City. “The better we understand them, the better that we can have these interventions.”

Mosquitoes that feed on people home in on a variety of cues when hunting, including body heat and body odor. The insects smell using their antennae and small appendages close to the mouth. Using three types of sensors in olfactory nerve cells, they can detect chemicals such as carbon dioxide from exhaled breath or components of body odor (SN: 7/16/15).

In previous work, researchers thought that blocking some sensors might hide human scents from mosquitoes by disrupting the smell messages sent to the brain (SN: 12/5/13). But even those sensor-deprived mosquitoes can still smell and bite people, says neurobiologist Margo Herre also of Rockefeller University.

So Goldman, Herre and colleagues added fluorescent labels to A. aegypti nerve cells, or neurons, to learn new details about how the mosquito brain deciphers human odors. Surprisingly, rather than finding the typical single type of sensor per nerve cell, the team found that individual mosquito neurons appear more like sensory hubs.

Genetic analyses confirmed that some of the olfactory nerve cells had more than one type of sensor. Some cells produced electrical signals in response to several mosquito-attracting chemicals found in humans such as octenol and triethyl amine — a sign the neurons could detect more than one type of odor molecule. A separate study published in April in eLife found similar results in fruit flies, which suggests such a system may be common among insects.

It’s unclear why having redundant ways of detecting people’s odors might be useful to mosquitoes. “Different people can smell very different from one another,” says study coauthor Meg Younger, a neurobiologist at Boston University. “Maybe this is a setup to find a human regardless of what variety of human body odor that human is emitting.”

Comets from the solar system’s deep freezer often don’t survive their first encounter with the sun. Now one scientist thinks he knows why: Solar warmth makes some of the cosmic snowballs spin so fast, they fall apart.

This suggestion could help solve a decades-old mystery about what destroys many “long-period” comets, astronomer David Jewitt reports in a study submitted August 8 to arXiv.org. Long-period comets originate in the Oort cloud, a sphere of icy objects at the solar system’s fringe (SN: 8/18/08). Those that survive their first trip around the sun tend to swing by our star only once every 200 years.
“These things are stable out there in the Oort cloud where nothing ever happens. When they come toward the sun, they heat up, all hell breaks loose, and they fall apart,” Jewitt says.

The Dutch astronomer Jan Oort first proposed the Oort cloud as a cometary reservoir in 1950. He realized that many of its comets that came near Earth were first-time visitors, not return travelers. Something was taking the comets out, but no one knew what.

One possibility was that the comets die by sublimating all of their water away as they near the heat of the sun until there’s nothing left. But that didn’t fit with observations of comets that seemed to physically break up into smaller pieces. The trouble was, those breakups are hard to watch in real time.

“The disintegrations are really hard to observe because they’re unpredictable, and they happen quickly,” Jewitt says.

He ran into that difficulty when he tried to observe Comet Leonard, a bright comet that put on a spectacular show in winter 2021–2022. Jewitt had applied for time to observe the comet with the Hubble Space Telescope in April and June 2022. But by February, the comet had already disintegrated. “That was a wake-up call,” Jewitt says.

So Jewitt turned to historical observations of long-period comets that came close to the sun since the year 2000. He selected those whose water vapor production had been indirectly measured via an instrument called SWAN on NASA’s SOHO spacecraft, to see how quickly the comets were losing mass. He also picked out comets whose movements deviating from their orbits around the sun had been measured. Those motions are a result of water vapor jets pushing the comet around, like a spraying hose flopping around a garden.

That left him with 27 comets, seven of which did not survive their closest approach to the sun.

Jewitt expected that the most active comets would disintegrate the fastest, by puffing away all their water. But he found the opposite: It turns out that the least active comets with the smallest dirty snowball cores were the most at risk of falling apart.

“Basically, being a small nucleus near the sun causes you to die,” Jewitt says. “The question is, why?”

It wasn’t that the comets were torn apart by the sun’s gravity — they didn’t get close enough for that. And simply sublimating until they went poof would have been too slow a death to match the observations. The comets are also unlikely to collide with anything else in the vastness of space and break apart that way. And a previous suggestion that pressure builds up inside the comets until they explode like a hand grenade doesn’t make sense to Jewitt. Comets’ upper few centimeters of material would absorb most of the sun’s heat, he says, so it would be difficult to heat the center of the comet enough for that to work.

The best remaining explanation, Jewitt says, is rotational breakup. As the comet nears the sun and its water heats up enough to sublimate, jets of water vapor form and make the core start to spin like a catherine wheel firework. Smaller cores are easier to push around than a larger one, so they spin more easily.

“It just spins faster and faster, until it doesn’t have enough tensile strength to hold together,” Jewitt says. “I’m pretty sure that’s what’s happening.”

That deadly spin speed is actually quite slow. Spinning at about half a meter per second could spell curtains for a kilometer-sized comet, he calculates. “You can walk faster.”

But comets are fragile. If you held a fist-sized comet in front of your face, a sneeze would destroy it, says planetary astronomer Nalin Samarasinha of the Planetary Science Institute in Tucson, who was not involved in the study.

Samarasinha thinks Jewitt’s proposal is convincing. “Even though the sample size is small, I think it is something really happening.” But other things might be destroying these comets too, he says, and Jewitt agrees.

Samarasinha is holding out for more comet observations, which could come when the Vera Rubin Observatory begins surveying the sky in 2023. Jewitt’s idea “is something which can be observationally tested in a decade or two.”