20 May 2026

Today’s Deep Dive challenges assumptions about vocal fry. But first, catch up on the latest science news, including how humans got the gift of grab and barrier zones that put the brakes on underwater earthquakes.

geology | Science advances

Volcanic sulfur may have doomed life on land during the end-Triassic extinction

More than 200 million years ago, part of planet Earth exploded. Extensive volcanic eruptions in a 10-million-square-kilometer area known as the Central Atlantic Magmatic Province (remnants of which are now spread across multiple continents) belched huge clouds of carbon dioxide, sulfur dioxide, and other gases into the atmosphere, bringing the Triassic to a chaotic close and paving the way for the reign of the dinosaurs during the Jurassic. While intense ocean acidification was likely responsible for the mass extinction of marine life, it’s less clear how these events led to catastrophe on land.

Now, scientists present evidence that sulfur was to blame . When the team examined sediment samples dating back to the Triassic-Jurassic boundary, they found that peak volcanic sulfur deposition coincided with a loss of floral diversity, as well as a large, temporary increase in the number of fern spores—something thought to occur after other terrestrial plants have died off. Because sulfur dioxide doesn’t stick around in the atmosphere as long as carbon dioxide, it’s commonly thought to do less long-term damage to ecosystems. But the pulses of volcanic sulfur emissions that occurred during the end-Triassic extinction may have caused a rapid increase in acid rain to terrestrial basins, the researchers report. Such a deluge would have poisoned the soil and killed off large swaths of plants, generating fuel for the rampant wildfires that followed.

“Recognizing this linkage,” the study authors write, “offers a useful framework for understanding how terrestrial and marine systems may respond differently to rapid sulfur-driven atmospheric perturbations arising from volcanic activity or anthropogenic emissions today.”

Read the Paper

paleoanthropology | news from Science

Did humans evolve from knuckle-walking ancestors? It’s all in the wrist

To trace the evolution of the human wrist, researchers created 3D reconstructions of the wrist bones of living and extinct primates. Laura Hunter

Humans are the only primates that walk upright all the time, an adaptation that has freed up our hands to more nimbly build tools, lug around food, and carry out other dexterous tasks. Hidden in the eight small bones of the wrist is an anatomical hint to where that gift of grab originated.

Now, the most comprehensive analysis of primate wrist bones to date—published in Proceedings of the Royal Society B—concludes that our wrists more closely resemble those of gorillas and chimpanzees than any other primate group, a similarity the authors link to a possible knuckle-walking past.

Scientists have long looked to wrist anatomy for clues to our evolutionary past, comparing our wrists to those of other living primates such as chimps and gorillas (which knuckle-walk) or capuchins and macaques (which flat-palm walk). Studying fossil hominins’ wrists for signs of these adaptations has proven tricky, as the wrist is a complex puzzle of eight or nine interlocking bones. So, researchers digitally reconstructed and quantified the exteriors of 2037 wrist bones across multiple living and extinct species, including monkeys and apes.

For nearly every bone examined, human wrist bones resembled the equivalents in knuckle-walking African apes far more than those of any other primate group. Human wrists also feature traits that help stabilize other primates’ wrists during knuckle walking—a sign of evolution’s opportunism. Features that once steadied the wrist in our distant ancestors laid the foundation for adaptations that yielded our dexterous wrists. “We became the human lineage,” said study co-author Laura Hunter. “But understanding where we started from is what tells you how we got here.”

Read the Full Story

seismology | Science

What makes a Pacific Ocean fault quake like clockwork?

Deep under water, along the seafloor, fractures in Earth’s crust have formed in places where blocks of rock have moved against one another over many years. These fractures, called faults, are the site of earthquakes that seem to happen like clockwork. At the Gofar transform fault, where two tectonic plates grind sideways past each other beneath the Pacific Ocean, magnitude 6 earthquakes repeatedly strike the same patches every 5 to 6 years.

Although scientists have long known about this unusual regularity, they didn’t fully understand what kept the ruptures from spreading farther along the fault. Now, using seismometers placed nearly 3 kilometers underwater, researchers have identified structurally complex “barrier zones” that may regulate these repeating earthquake cycles . Over the course of a multiyear experiment, these instruments picked up hundreds of thousands of seismic events, enough for the team to reconstruct more than 71,000 earthquake locations from the 2020 sequence alone. Researchers also compared detailed recordings from two nearly identical earthquake cycles, from 2008 and 2020, on different segments of the Gofar fault. For both events, areas adjacent to the main rupture became intensely active with swarms of tiny earthquakes and foreshocks in the days or weeks before the main event, then abruptly quieted afterward.

Rather than acting as smooth, stable fault sections, the barriers are messy, fragmented regions made up of multiple fault strands and small bends. So, when a rupture front arrives, the sudden jolt causes pressure inside the fluid-filled rock to drop sharply, stopping the earthquake. Similar barriers may be widespread across the ocean floor, which could explain why underwater earthquakes stay smaller than often expected.

Read the paper

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deep dive

Britney Spears is known for her iconic raspy voice. RHYS ADAMS VIA WIKIMEDIA COMMONS | CC BY

Vocal fry isn’t a girly thing

In the early 2010s, headlines spoke of an epidemic: Vocal fry, that gravelly buzz that occurs when people speak in their lowest vocal register, was creeping into the speech patterns of young female speakers of American English. Pop singers like Britney Spears are known to employ this characteristically creaky effect, which is caused by the slow, irregular fluttering of the vocal cords that commonly happens at the end of an uttered sentence. It is typically associated with young women, and many people find it irritating. One PloS One study found, for example, that women who speak with vocal fry are viewed as “less competent, less educated, less trustworthy, less attractive, and less hirable.” These negative perceptions were stronger for female voices compared to male ones.

But according to research summarized at last week’s meeting of the Acoustical Society of America, stereotypes about vocal fry are just that—stereotypes.

Linguistics researcher Jeanne Brown collected speech samples from 49 Canadians and analyzed them for the acoustic markers of vocal fry, including low pitch, irregular voicing, and increased closure of the vocal cords. That research, published last year in the Journal of Phonetics, found that men’s voices are actually creakier than women’s. What’s more, voice creakiness appears to increase with age—further challenging the assumption that vocal fry is some kind of fad or trend among young women.

In a second experiment, Brown asked 40 Canadian English listeners to rate the perceived creakiness of different voice recordings, which had been altered so that the level of fry varied and the perceived gender of the speaker was ambiguous. The recordings were also paired with pictures of male and female faces. Participants in that study, published in the current issue of Laboratory Phonology, correctly identified creaky voices, but the primary marker for their perception of vocal fry was low pitch, not gender.

“The conflict between that finding and everyday perception, where women are routinely flagged as creakier, suggests the bias is real but socially constructed, rather than grounded in how women actually sound,” Brown said in a statement. So, even though people can accurately identify vocal fry based on pitch in controlled settings, negative social and cultural biases may cause them to more selectively hear it in the voices of young women in everyday situations. After all, a signature vocal growl is also common among male singers, podcast hosts, and social media influencers, although these individuals are rarely criticized for it or viewed as annoying. “Maybe it’s about the whole interpretation of what this person stands for, what this person represents, the social group this person is trying to show that they’re a part of,” Brown told New Scientist . “It could be that people are making judgments about that in addition to the way that their voice sounds.”

Et Cetera

Against the grain

The Philippine government has taken a step toward approving a genetically modified (GM) rice with enhanced levels of iron and zinc, a move that could help improve children’s health but may face challenges from opponents of GM crops.

Read more at ScienceInsider

Catch-up snooze

Sleep tracking data from 85,000 people suggests getting extra sleep the day after a shortened night of slumber can help reduce negative health effects—specifically, the risk of early death.

Nature Communications Paper | Read more at News from Science

Bones in stone

A large stone vessel recovered from northern Laos held the remains of at least 37 people, suggesting that thousands of other “jars” throughout the region were used in ancient burial ceremonies.

Antiquity Paper | Read more at Science News

I look forward to reading more details when they’re published, but until there’s a peer-reviewed paper I might as well give expert commentary on a YouTube ad.
—Louise Johnson, University of Reading

EXPERT REACTION ROUNDUP | 19 May 2026 | science media centre

Scientists respond to a press release from Colossal Biosciences, a company that aims to “de-extinct” lost species, announcing that chicks have been hatched from its artificial egg system.

Last but not least

In honor of World Bee Day, I’d like to remind everyone just how amazing these insects are. Just look at bumble bee queens, which can survive days underwater without drowning.

Phie Jacobs, General Assignment Reporter, Science

With contributions from Michael Greshko and Ana Georgescu

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