There were many oversized versions of animals we know today, including the giant beaver. It lived in the lakes and streams, but there is no evidence it built dams like modern beavers do. Giant beavers died out along with the other Pleistocene giants between 9,000 and 11,000 years ago. The musk ox is an animal uniquely adapted for arctic conditions. The behavior of musk oxen can be lifesaving, too.
Adults gather in a protective wall to keep the calves safe from predator attacks and severe storms.
Musk oxen inhabited much of Eurasia and North America during the Pleistocene, but now survive only in parts of Greenland and northern Canada. Back to Top Peccary Peccaries were extremely common in Missouri and elsewhere in North America during the Pleistocene. These members of the pig family averaged about 4 feet in length, much larger than their modern cousins. They inhabited the plains and forest, defending themselves against predators with their needle-sharp tusks. Smaller peccary species still live in the southwestern United States, and in Central and South America.