Placental mammals like elephants, bats and humans evolved from small, insect-eating mammals, a study led by Stony Brook University has found. The research resolves many questions of mammal evolution.
Comparing both DNA and body shapes, the researches found placental mammals arose after the extinction of the dinosaurs. Previous thought based on genetics held that placental mammals evolved while dinosaurs still lived.
The study also suggests that African mammals such as elephants evolved in the Americas and dispersed into Africa. How they did so remains a mystery.