The dinosaurs needed to go extinct for the mammals, and humans, to arise. At least that’s what researchers have been thinking for decades. But a new study indicates that at least one group of ancient mammals was already expanding 20 million years before the dinosaurs were wiped from the Earth. Analysis of ancient mammal teeth indicates they were able to take off not because dinosaur die-off made way for them, but because they discovered a new food source that others weren’t consuming.
Link: LiveScience.com