"DNA Reveals the Real Lives of (...) Dire Wolves"

 

Extraits de cet article:

The dire wolf (...) powerful predator that roamed North America up to about 11,000 years ago, or perhaps even later, preying on large animals like extinct horses, bison, sloths and even mammoths.

(...) The last common ancestor of the gray wolf and the dire wolf was about 5.7 million years ago, the researchers reported. And another surprise was that the dire wolf didn’t seem to interbreed with other species — as dogs, wolves, coyotes and other canids do. In evolutionary terms, it met a lonely end.

(...) The problem was not a lack of old bones. The vast majority come from the La Brea Tar Pits in Los Angeles County, where the remains of about 4,000 animals have been recovered. Tar apparently plays havoc with recoverable DNA and until now, nobody had been able to sequence the dire wolf’s genome.

(...) The long genetic isolation is significant in another way.

Larisa DeSantis, a paleontologist at Vanderbilt University, who was not involved in the research, said it “is consistent with the idea of a North American origin of dire wolves.”

They were here at least 250,000 years ago, and they were still around, although nearing the end of their existence, when the first humans were arriving in the Americas, perhaps 15,000 years ago.

“They were not this ginormous mythical creature, but an animal that most likely interacted with humans,” Dr. Perri said.

(...) As to why the dire wolf went extinct and wolves survived, the authors speculated that its long genetic isolation and lack of interbreeding with other species may have made it less able to adapt to the disappearance of its main prey species. More promiscuous species like gray wolves and coyotes were acquiring potentially useful genes from other species.

Laurent Frantz, an ancient DNA specialist at Ludwig Maximilian University in Munich and one of the paper’s authors, said that finding was a reminder of the evolutionary success of gray wolves. Their wide variation in size and ability to adapt to different prey species helped them escape the fate of the dire wolf. Now, of course, they face many threats in Europe and the United States.

“It’s the ultimate carnivore survivor,” he said, “until it faces humans.”