The rise of mammals, the Genus Homo, and the ongoing extinction event
The mammal survivors of the K-T boundary event essentially repeated the kind of proliferation enjoyed by the dinosaurs during the Mesozoic. So many new mammal types emerged, and the preservation of them was so good, that it has been possible to subdivide the last 65 million years in great detail. The increase in size seen for the dinosaurs has also occurred for mammals, and there is even a parallel with mammals taking to the air and going back to the oceans. The parallel increase in brain size and complexity eventually led to the Genus Homo, and an animal with both complex technological (tool-using) capabilities, and the capacity to pass on knowledge with sophisticated culture. The current state, with the continued expansion of human populations, spreading essentially world-wide, has led more or less directly to extinction of some species and the possibility of an ongoing extinction event that could rival those of the distant geologic past. How this might unfold in the near and long term is an interesting open question.
KeywordsHomo/human Mammal Brain Intelligence Primate Culture/cultural Tool Overkill Indigenous peoples Climate change
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