Tuesday, November 30News That Matters

Tag: Paleontology

Why Was This Ancient Mammoth Tusk Discovered at the Bottom of the Ocean?

Technology
Mammoth tusks that are over 100,000 years old are “extremely rare,” Mr. Mol added, and studying one could give scientists new insights about the Lower Paleolithic, a poorly understood era of Earth’s history.Scientists know that around 200,000 years ago Earth was experiencing a glacial period and our ancestors were migrating out of Africa. But they don’t know exactly how the planet’s changing climate affected mammoths and other large animals during this time. What is also unclear is how arrival to North America altered the genetic diversity of mammoths.“We don’t really know much of anything about what was happening during that time period,” Dr. Fisher said. “We don’t have access to a lot of specimens from this time period and that’s due in large part to the fact that getting access to sedim...
‘Penis Worms’ May Have Been the First Hermits

‘Penis Worms’ May Have Been the First Hermits

Technology
Consider this evolutionary dilemma, faced by the aquatic and squishy: How do you survive in hostile, predator-filled oceans?Squid rely on speed or camouflage. Snails develop complex shells. Hermit crabs borrow those complex shells when other animals aren’t using them, trading them out for bigger models as they grow.This sheltering strategy was believed to have emerged 180 million years ago in the Jurassic Period, when hermit crabs’ ancestors appeared in oceans, said Martin Smith, a paleontologist at the University of Durham in England. But in a study published Monday in Current Biology, Dr. Smith and colleagues suggest that the practice of hiding out in borrowed shells actually dates back hundreds of millions of years earlier, to the dawn of complex ecosystems.The early hermits in question...

Antarctica Was Once a Land of Fire and Not Ice

Technology
Imagine the forests of Chilean Patagonia: wet and cold, dense with monkey puzzle trees and other hardy conifers. Now imagine it with dinosaurs walking around. And on fire.This is what Antarctica was like 75 million years ago during the Cretaceous period, an era known by researchers as a “super fire world.” A paper published last month in Polar Research by Flaviana Jorge de Lima of the Federal University of Pernambuco and other scientists in Brazil proves that these conflagrations did not spare any continent, even one that is today notorious for its dry, inhospitable climate and largely vegetation-free landscape.Although research on prehistoric wildfires — properly called “paleofires” — has been going on for decades, much of it has concentrated on the Northern Hemisphere. Antarctica was “fi...

As Earth Warms, Human History Is Melting Away

Technology
To hear more audio stories from publications like The New York Times, download Audm for iPhone or Android.For the past few centuries, the Yup’ik peoples of Alaska have told gruesome tales of a massacre that occurred during the Bow and Arrow War Days, a series of long and often brutal battles across the Bering Sea coast and the Yukon. According to one account, the carnage started when one village sent a war party to raid another. But the residents had been tipped off and set an ambush, wiping out the marauders. The victors then attacked the undefended town, torching it and slaughtering its inhabitants. No one was spared.For the last 12 years, Rick Knecht has led an excavation at a site called Nunalleq, about 400 miles west of Anchorage. “When we began, the hope was to learn something about ...
How Did Elephants and Walruses Get Their Tusks? It’s a Long Story.

How Did Elephants and Walruses Get Their Tusks? It’s a Long Story.

Technology
Elephants have them. Pigs have them. Narwhals and water deer have them. Tusks are among the most dramatic examples of mammal dentition: ever-growing, projecting teeth used for fighting, foraging, even flirting.So why, across the broad sweep of geologic history, do such useful teeth only appear among mammals and no other surviving groups of animals? According to a study published Wednesday in the journal Proceedings of the Royal Society B, it takes two key adaptations to teeth to make a tusk — and the evolutionary pathway first appeared millions of years before the first true mammals.Around 255 million years ago, a family of mammal relatives called dicynodonts — tusked, turtle-beaked herbivores ranging in stature from gopher-size burrowers to six-ton behemoths — wandered the forests of the ...

Dinosaurs May Have Been Socializing Nearly 200 Million Years Ago

Technology
Paleontologists have found the earliest known evidence that dinosaurs lived in herds — unlike reptiles, and more like penguins and other birds do today — and socialized with each other by age groups.The scientists, working a rich deposit of fossils at a site in Argentina’s province of Santa Cruz, at the southern tip of South America, found more than 100 eggs and the skeletons of 80 individuals ranging in age from embryos to adults.All of the fossils, including the embryos inside the eggs, are of the species Mussaurus patagonicus. These dinosaurs were about 10 feet high and 26 feet in length when fully grown, with a long tail balanced by an equally long neck that ends in a head that seems too small for the enormous animal it is attached to. This is the only place Mussaurus remains have ever...
Ancient-DNA Researchers Set Ethics Guidelines for Their Work

Ancient-DNA Researchers Set Ethics Guidelines for Their Work

Technology
The authors of the new paper intentionally chose to invite only active practitioners of ancient DNA research, according to Kendra Sirak, a paleogeneticist at Harvard Medical School and one of the authors. They also emphasize that these guidelines come from a particular group of scholars in the ancient DNA community.“We realized that what’s lacking in this field is a statement from a group of practitioners from all over the world, so that’s what we wanted to contribute here,” said Dr. Sirak, who works in the lab of David Reich, one of the leading experts in ancient DNA.The new paper is not the first published set of ethics guidelines on the issue. In 2018, a group of scientists based in North America published guidelines for ancient DNA research — the first recommendations approved by a pro...

Ancient Footprints Suggest Humans Arrived In Americas During Ice Age

Technology
Ancient human footprints preserved in the ground across the White Sands National Park in New Mexico are astonishingly old, scientists reported on Thursday, dating back about 23,000 years to the Ice Age.The results, if they hold up to scrutiny, would rejuvenate the scientific debate about how humans first spread across the Americas, implying that they did so at a time when massive glaciers covered much of their path.Researchers who have argued for such an early arrival hailed the new study as firm proof.“I think this is probably the biggest discovery about the peopling of America in a hundred years,” said Ciprian Ardelean, an archaeologist at Autonomous University of Zacatecas in Mexico who was not involved in the work. “I don’t know what gods they prayed to, but this is a dream find.”For d...
A New Company With a Wild Mission: Bring Back the Woolly Mammoth

A New Company With a Wild Mission: Bring Back the Woolly Mammoth

Technology
At the time, researchers were learning how to reconstruct the genomes of extinct species based on fragments of DNA retrieved from fossils. It became possible to pinpoint the genetic differences that set ancient species apart from their modern cousins, and to begin to figure out how those differences in DNA produced differences in their bodies.Dr. Church, who is best known for inventing ways of reading and editing DNA, wondered if he could effectively revive an extinct species by rewriting the genes of a living relative. Because Asian elephants and mammoths share a common ancestor that lived about six million years ago, Dr. Church thought it might be possible to modify the genome of an elephant to produce something that would look and act like a mammoth.Beyond scientific curiosity, he argue...
‘Spaceship-Shaped’ Fossil Reveals Hungry Predator of Ancient Oceans

‘Spaceship-Shaped’ Fossil Reveals Hungry Predator of Ancient Oceans

Technology
Some 506 million years ago, a predator swept over the silt bottoms of the Cambrian ocean. Its rake-like feeding arms sifted through the murk it raised, funneling soft-bodied worms into a puckering, circular mouth.In 2018, a team of paleontologists from the Royal Ontario Museum discovered the preserved shell of that ancient hunter during a fossil hunting expedition in the Canadian Rockies. On Wednesday in the journal Royal Society Open Science, the team identified the 19-inch animal, which they named Titanokorys gainesi, as one of the earliest-known large predators on Earth.“At a time when most animals were the size of your little finger, this would have been a very large predator and probably near the top of the food chain,” said Joe Moysiuk, a Ph.D. student at the University of Toronto an...