"Buitreraptor is one of those special fossils that tells a bigger story about the Earth's history and the timing of evolutionary events," said Peter Makovicky, curator of dinosaurs at The Field Museum."It not only provides definitive evidence for a more global distribution and a longer history for dromaeosaurs than was previously known, but also suggests that dromaeosaurs on northern and southern continents took different evolutionary routes after the landmasses that they had occupied, drifted apart." The Buitreraptor fossil was found in northwestern Patagonia (the southern end of the South America continent) about 700 miles southwest of Buenos Aires.
Here's why that's important: About 200 million years ago, Earth had just one giant land mass called Pangea.
Toward the end of the Jurassic period, it split in two.
Evidence that they existed in the Southern Hemisphere has been mounting.
Today's announcement of a well-preserved fossil represents the first definitive evidence that dromaeosaurs roamed South America as well.
The scientists say they found what appear to be hammerstones and stone anvils at the site, showing that ancient humans had the manual skill and knowledge to use stone tools to extract the animal's Bone Marrow and possibly to use its bones to make tools.
The site was named Cerutti Mastodon site, in honor of Richard Cerutti, who made the discovery and led the excavation.The discovery changes the understanding of when humans reached North America.The study, to be published this week in the science journal Nature, said the numerous limb bones fragments of a young male mastodon found at the site show spiral fractures, indicating they were broken while fresh.It has been widely accepted that groups of peoples entered the American hemisphere from northeastern Siberia, perhaps by a land bridge across the Bering straits of Alaska that might have existed then, (This at some time in the Late Pleistocene, or Ice Age).There is already abundant evidence that by 11,000 B.C, hunting peoples had occupied most of North America, south of the glacial ice cap covering the northern part of North America.