Prehistoric Zoo: Who ruled the planet after the dinosaurs For starters, how about a killer bird as tall as you and a rhino/pig-thing the size of your house. Meet these &#151 and other &#151 fantastic beasts who rose from the asteroid's ashes. Beast Gallery: Get a low-tech look at 18 marvelously bizarre post-dinosaur creatures. Real Beasts of the Ice Age has already aired, but you can check it ...

Of Mastodons, Mammoths and Other Giants of the Pleistocene Bones of a Mastodon. During the Pleistocene Epoch, from about 1.5 million to 10, 000 years ago, the world grew cold. Great sheets of ice, sometimes a thousand feet thick, moved down from the north gouging out the land. These harsh conditions seemed to encourage the development of giant mammals (Probably because larger animals are better ...

The last Ice Age peaked about 20, 000 years ago, after which the Earth again began to warm. Fossil evidence shows that by about 15, 000 years ago, Ice Age people were roaming the plains and forests in North America, hunting enormous mammals with stone-pointed spears. Most of those animals were extinct by about 10, 000 years ago. Did changes in climate or over-hunting by man cause the demise of Ice ...