Neanderthals lived in Europe for thousands of centuries, and during that time, they had to watch their step. Mammoths, woolly rhinos, and saber-tooth cats were common in the region, and the caves these human relatives would sometimes enter for shelter were often already occupied by cave bears, the heaviest adults of which may have weighed over 2,000 pounds.

Today, controversy swirls around the question of why all these large animals eventually disappeared. Some scientists think they were victims of the last glacial maximum, which peaked around 26,500 years ago. Other experts have argued that the appearance of a new human species with a knack for hunting, Homo sapiens, could have driven the unfortunate beasts to extinction.

Now, research presented in the