Mammals' unique arms started evolving before the dinosaurs existed
Monday, March 18, 2019 - 22:00
in Paleontology & Archaeology
One of the things that makes mammals special is our diverse forelimbs -- bat wings, whale flippers, gibbon arms, and cheetah legs have evolved to do different, specialized tasks. Scientists wanted to see where this mammalian trait started evolving, so they examined fossils from early mammal relatives to see when the upper arm bones started diversifying. They discovered that the trait took root 270 million years ago -- 30 million years before the earliest dinosaurs existed.