Prehistoric mammals are various groups of mammals that lived over 10,000 years ago. The earliest mammals arose from mammal-like reptiles in the middle of the Jurassic period and remained subdued by the reign of the dinosaurs.
The lineages of many varieties continued through the Tertiary period where they reached incredible dinosaur-like sizes. Most became extinct in the last ice age.
| Basilosaurus |
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| Basilosaurus was a genus of cetacean that lived from 40 to 37 million years ago in the Eocene. Its fossilized remains were first discovered in the American South, and were initially believed to be some sort of reptilian sea monster, hence the suffix "saurus"... |
| Mammoth |
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| A mammoth (from Russian мамонт) is any of a number of an extinct genus of elephant, often with long curved tusks and, in northern species, a covering of long hair. They lived during the Pleistocene epoch from 1.6 million years ago to around 10,000 years ago... |
| Saber-toothed Cat |
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| The term saber-toothed cat describes numerous cat-like species that lived during various parts of the Cenozoic and evolved their saber-toothed characteristics entirely independently. The saber-tooth morphology is an excellent example of convergent evolution as it occurred repeatedly and independently in at least four distinct mammalian groups... |
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