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The new find suggests such raptors go back much further in time than previously thought.Until recently, dromaeosaurs had been found only in Asia and North America and only in the Cretaceous period, which ran from 145 million to 65 million years ago.By Gisela Crespo, CNN, April 26, 2017 The remains of a mastodon discovered during a routine excavation in California shows possible human activity in North America 130,000 years ago -- or about 115,000 years earlier than previously thought.Paleontologists with the San Diego Natural History Museum discovered the remains of the elephant-like animal more than 20 years ago.Since dromaeosaurs had only been found in places that used to be part of Laurasia, scientists figured that the beasts evolved into being after Pangea split.But the Buitreraptor fossil in South America, which dates back 90 million years and closely resembles fossils from the North, means one of two things: Either dromaeosaurs existed when Pangea was intact; or the newfound Buitreraptor and its northern look-alikes evolved separately yet with remarkably similar results.It has a long head and long tail and wing-like forelimbs.Its serrated teeth, like steak knives, suggest it was a carnivore.
"This is a whole new ball game," Steve Holen, co-director of the Center for American Paleolithic Research and the paper's lead author, told CNN.
What we call Laurasia eventually became North America, Asia and Europe.
The other chunk Gondwana, developed into the continents of the Southern Hemisphere and India.
As with dromaeosaurs, new discoveries are forcing scientist to re-consider their earlier theories of Human presence in the American hemisphere as well.
The time of the first peopling of Mesoamerica remains a puzzle, as it does for that of the Americas in general.