Researchers from Dartmouth argue that an asteroid or comet impact was to blame for the disappearance of large mammals in the Younger Dryas period nearly 13,000 years ago. The impact, which scientists believe occurred in Quebec, caused dramatic global cooling. Droplets of solidified molten rock expelled by the impact were found in Quebec and as far south as Pennsylvania and New Jersey, however scientists have yet to find the impact crater. Not only did the event kill off North American mastodons, camels, giant ground sloths and saber-toothed cats, but it also affected humans who had to move from a hunting lifestyle to growing and gathering some of their food.
[ Read the Article: Large Mammals Of Younger Dryas Wiped Out By Asteroid ]