The extinction of dinosaurs about 65 million years ago is generally thought to be due to the devastating consequences of asteroids hitting the Yucatan Peninsula, and only a few surviving small mammals have continued to breed since then. Many new species have emerged, replacing once Space occupied by dinosaurs, some of which become huge. In the Americas, this "large fauna" includes giant sloths, camels and llamas, as well as a variety of bison, elk, cattle, giant beavers, mammoths And mastodons. Before these herbivores came out, during the past 65 million years, some terrible predators existed on the earth, including giant short-faced bears weighing two tons, a lion, and several saber-toothed tigers. And giant dire wolves. In Europe, there have been countless species of woolly mammoths, cave bears, giant elk and other species. As for other continents, spectacular hairy giants have also appeared. The text is intended to explain:. ['The world inhabited by early human ancestors was dominated by large mammals.', 'The world inhabited by early human ancestors was dominated by large mammals.', 'There is no trace of human activity in the early world dominated by mammals.', 'Humans have always been accompanied by animals, including large mammals.']