Author Archives: Attention to the Unseen

A new field called paleoepigenetics is probing how evolution responds to sudden stress

Ferris Jabr writes: Every year the paleontologist Alan Cooper meets up with a band of miners in the Yukon. As the miners go about their work, spraying massive jets of water at frozen mud and silt to excavate gold, they also expose animal remains from the Pleistocene, between 2 million and 12,000 years ago. Back then, North America was a riot of big mammals. Antelope, camels, llamas, and indigenous horses roamed the vast plains; lions, saber-toothed cats, and dire wolves prowled for prey; and giant ground sloths lumbered along, stripping tree branches of leaves and fruit.

But, by the time the planet transitioned to the current geological epoch, the Holocene, the vast majority of those species had gone extinct, most likely due to climate change or hunting by humans. Climate change in the Pleistocene was “huge, frequent, and rapid,” says Cooper, director of the Australian Centre for Ancient DNA at the University of Adelaide. “Sometimes a change of 10 degrees centigrade over a space of a decade or two.” It’s difficult for animals to cope with such dramatic shifts through standard evolution by natural selection, which often takes decades — even millennia — to spread advantageous genetic mutations and hone adaptations. [Continue reading…]

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The red wolf and a new theory about how evolution actually works

Ben Crair writes: Since the red wolf was originally classified as an endangered species, biologists have studied it intensely — sequencing its DNA, scrutinizing its morphology, and piecing together its evolutionary history. And they’ve put forward a compelling new theory: The red wolf, an animal the U.S. government has spent decades and millions of dollars attempting to save from extinction, may not actually be a distinct species at all.

The implications of this idea extend far beyond the swamps and farms of North Carolina, threatening the very foundations of biology itself. “Not to have a natural unit such as the species would be to abandon a large part of biology into free fall, all the way from the ecosystem down to the organism,” the noted biologist and theorist E.O. Wilson wrote in his 1992 book The Diversity of Life. And yet, the research into the red wolf challenges our accepted notions about how species are defined—and about how evolution actually works. [Continue reading…]

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Is Facebook luring you into being depressed?

Chelsea Wald writes: In his free time, Sven Laumer serves as a referee for Bavaria’s highest amateur football league. A few years ago, he noticed several footballers had quit Facebook, making it hard to organize events on the platform. He was annoyed, but as a professor who studies information systems, he was also intrigued. Why would the young men want to give up Facebook? Social scientists had been saying the social network was a good thing.

“At the time, the main paradigm in social networking research was that Facebook is a positive place, it’s a place of happiness, it’s a place where you have fun, you get entertained, you talk to friends, you feel amused, accepted,” says Hanna Krasnova, an information systems researcher at the University of Bern in Switzerland. Influential studies had shown that the social capital we earn on social media can be key to our successes, big and small. Our virtual connections were known to help us access jobs, information, emotional support, and everyday favors. “Everyone was enthusiastic about social media,” Laumer says.

Laumer, an assistant professor at Otto-Friedrich University in Germany, suspected that quitting Facebook was a classic response to stress. He knew other researchers had looked at something called “technostress,” which crops up in workplaces due to buggy interfaces or complex processes. But that didn’t really fit with Facebook, which is easy to use. Something else seemed to be stressing people out. “We thought there was a new phenomenon on social media in particular,” Laumer says.

Through probing interviews, surveys, longitudinal studies, and laboratory experiments, researchers have begun to shift the paradigm, revealing that Facebook, Twitter, Instagram, Snapchat, and their ilk are places not only of fun and success, but of dark, confronting, and primal human emotions—less Magic Kingdom and more creepy fun house. In many ways, researchers say, these platforms are giant experiments on one of our species’ most essential characteristics: our social nature. So it shouldn’t be a surprise there are unintended consequences. [Continue reading…]

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The human flock

Helen Macdonald writes: There are 12 of us by the lake. Some have set out spotting scopes on tripods upon the grass; others carry binoculars. Silently we stand and wait for the Hungarian dusk. The sun slips behind an expanse of steely water, and the air grows colder. Then we hear a faint noise like baying hounds or discordant bugles, at first hardly discernible through the wind rattling the reeds. It grows into an unearthly clamor. ‘‘Here they come!’’ someone whispers. Overhead, a long, wavering chevron of beating wings is inked across the darkening sky. Behind it flows others, and there are others behind them, all passing overhead in ever-increasing waves, filling the air with an astonishing barrage of noise and beauty.

The birds above us are long-necked, graceful Eurasian cranes. Every autumn more than a hundred thousand of them stop off on their southward migration from Russia and Northern Europe to spend a few weeks in the Hortobagy region in northeastern Hungary, feeding on maize left in the fields after the harvest. Every night they fly to roost in huge numbers in the safety of shallow fish-farm lakes, attracting wildlife tourists who come here to witness the spectacle of their evening flights. Similarly impressive congregations can be seen in many other places. In Nebraska, more than half a million sandhill cranes fatten up in cornfields before continuing their spring migration; in Quebec, watchers thrill at blizzards of snow geese blotting out the sky as they rise from the St. François River. In Britain, clouds of wintering starlings flying to their roosts draw crowds of all ages.

Standing so close to such vast masses of birds affects everyone differently: Some people laugh, some cry, others shake their heads or utter profanities. Language fails in the face of immense flocks of beating wings. As I stare up in awe, it strikes me that this is, at heart, a kind of modern secular pilgrimage.

Our brains are built to wrest familiar meaning from the confusions of the world. Watching the cranes at dusk, I see them turn first into strings of musical notation, then mathematical patterns. The snaking lines synchronize so that each bird raises its wings a fraction before the one behind it, each moving flock suddenly resolving itself into a filmstrip showing a single bird stretched through time. It is an astonishing image that makes me blink in surprise. Part of the allure of flocking birds is their ability to provoke optical illusions. I remember my astonishment as a child watching thousands of shorebirds flying against a gray sky vanish and reappear in an instant as the birds turned their countershaded bodies in the air. Perhaps the best-known example is the hosts of European starlings that assemble in the sky before they roost. We call them murmurations, but the Danish term, sort sol, is better: black sun. It captures their almost celestial strangeness. Standing on the Suffolk coast a few years ago, I saw a far-flung mist of starlings turn in a split second into an ominous sphere like a dark planet hanging over the marshes. Everyone around me gasped audibly before it exploded in a maelstrom of wings. [Continue reading…]

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Evidence that first toolmakers predated the genus Homo

Discover reports: Thanks to a wrong turn, a stroke of luck and keen eyes, husband and wife research partners Sonia Harmand and Jason Lewis of Stony Brook University could rewrite our understanding of tool use among hominins. With their team from the West Turkana Archaeological Project, the pair have found evidence that a species predating the genus Homo may have made the first stone tools.

In July 2011, Harmand and Lewis and their colleagues were scouting for sites in the area around northern Kenya’s Lake Turkana. There are no roads in this remote region, so Harmand was forced to drive in dry creek beds while Lewis navigated with a GPS device. It’s all too easy to become disoriented in this kind of terrain; at a certain juncture where the GPS indicated a right turn, she mistakenly went left. They soon found the way blocked by bushes. Unable to drive farther, they climbed a small hill to get their bearings. From the top of the rise, the team gazed down on what Harmand describes as a uniquely beautiful landscape.

“I felt certain it contained hidden areas waiting to be explored,” she says. Everyone fanned out to investigate. “We were only 10 people, working far from each other with walkie-talkies. Around 9 in the morning, we had a call from our local Turkana team member, Sammy Lokorodi. He said, ‘You should come where I am because I think I’ve spotted something very interesting.’ ”

He found stone tools sticking out of an eroding creek bed. The surface above had a dark, weathered patina, but the areas around the rocks were light, suggesting they had been only recently exposed. Harmand knew at once this was an important find because the layers in which the tools were embedded were dated to more than 2.7 million years old.

Paleomagnetic dating — matching magnetic properties in the sediments surrounding a fossil or artifact to ancient reversals in the Earth’s magnetic poles to determine age — later determined the tools had to have been made 3.3 million years ago. Despite the tools’ simple form and huge size, some almost 8 inches across, the angle and patterns on the rocks’ edges showed repetitive strikes that could not have resulted from erosion or other natural processes. Publishing the discovery in Nature in May, Harmand and Lewis dubbed the assemblage the Lomekwi 3, after the area where the tools were found. [Continue reading…]

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DNA evidence reveals that the people who civilized Europe were migrants

The New York Times reports: Before the rise of agriculture, Europe was home to a population of hunter-gatherers. Then a wave of people arrived whose DNA resembles that of people in the Near East. It’s likely that they brought agriculture with them.

Finally, about 4,500 years ago, a nomadic population from the steppes of Russia, known as the Yamnaya, swept into Europe.

The analyses that revealed these migrations were based on dozens of ancient European genomes. But in a study published Monday in Nature, David Reich, a geneticist at Harvard Medical School, and his colleagues analyzed the genomes of 230 people who lived between 8,500 and 2,300 years ago.

The enormous sample size has provided enough data to track individual genetic variations as they become more or less common through the history of ancient Europe.

The remains that Dr. Reich and his colleagues analyzed DNA from span the entire continent of Europe. They also include the Yamnaya as well as 21 people who lived in a region of Turkey called Anatolia 8,500 years ago. The study marks the first time scientists have been able to analyze the DNA of the people who brought farming to Europe. [Continue reading…]

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