"To have it turn out to be 40 per cent, it's just like, wow!" says James Chatters at McMaster University in Canada. In fact, when compared with other animals alive at this time, the boy's diet was more similar to that of the carnivorous scimitar-toothed cat than that of the omnivorous short-faced bear, he says. Artefacts such as stone tools show that around 15,000 years ago, as the ice retreated after the last glacial maximum, people from Asia crossed the land bridge that existed across the Bering Strait and moved into North America. These people, known as the Clovis culture, developed distinctive stone tools characterised by large, finely made stone points.