Extinction in the middle of the upper Cretaceous period 80 million years ago, there were hundreds of species of dinosaurs, which covered the 14 families, of which two families were carnivorous, others feed on plants. All but members of one family of numerically small, were true giants and weighed more than 2-3 tons. Then the number of families and species of dinosaurs became gradually decrease. In the last five million years of the Cretaceous period, this process is accelerated, and the herbivores disappear faster than carnivores. Finally, 65 million years ago, giant reptiles disappeared completely. What was this caused by the gradual decline and ultimate extinction? Change Many paleontologists believe climate that the immediate cause was climate change. Dinosaurs were in need of warmth.
Their evolution proceeds in the climatic conditions are extremely different from the present. The average annual temperature on Earth was higher, and in such northern regions as Alaska, the climate was almost tropical, and within a year the temperature was almost everywhere even without such sharp distinctions between the seasons, as in our time. About Eighty million years ago, when dinosaurs began to disappear from the face of the Earth, temperatures around the world began to fall gradually, and also the difference between the extreme values of its annual has become much more. Nevertheless, even 50 north latitude found many fossils of dinosaurs end of the Cretaceous period, so that, apparently, and at that time – when they became extinct on our planet was a lot of areas with high and stable temperature. .