LARAMIE, WYOMING—A team of scientists from the University of Wyoming compiled radiocarbon dates from the fossils of now-extinct animals from North and South America, and looked at how those dates correspond to the evidence of human colonization of the New World. They found that, as geoscientist Paul Martin predicted in 1973, the decline and extinction of mammoths, mastodons, camels, horses, and ground sloths can be used to map the spread of the migrating humans who hunted them for food. Large mammals began to disappear from Alaska and the areas near the Bering Strait between 13,300 and 15,000 years ago; from the contiguous United States between 12,900 and 13,200 years ago; and from South America between 12,600 and 13,900 years ago. “The north to south time-transgressive pattern is striking, and, barring significant new data, it would be difficult to reconcile this pattern with the extinction hypotheses that invoke a single climatic, ecological or catastrophic extinction mechanism across the entirety of the Americas,” the researchers wrote in the Proceedings of the National Academy of Sciences, reported in a press release. For more, go to "New Dates Link Humans to Australia's Megafauna Extinctions."