Sentences with phrase «placental mammals appeared»
The split into the three subfamilies likely occurred before, or around, the time placental mammals appeared (approximately 180 million to 220 million years ago).
http://www.jcvi.org/
According to the new tree, the first placental mammals appeared around 65 million years ago, not 100 million years ago or more, as some molecular data have suggested.
Not exact matches
«It now appears that the major diversification of placental mammals closely followed the extinction of dinosaurs 66 million years ago, an event that would have opened up ecological space for mammals to evolve into.»
The earliest placental mammal fossils appear only a few hundred thousand years after the mass extinction, suggesting the event played a key role in diversification of the mammal group to which we belong.»
Its high - crowned teeth also appeared to be slow growing like modern placental mammals.