Cool – Xochielt Sanchez #xochielt
Answer by Adriana Heguy:
No. The ancestors of whales were land mammals. The earliest known whale ancestor lived 50 million years ago and was called Pakicetus (the fossil is from Pakistan):
It looked like this:
After Pakicetus, the next fossil that is in the whale lineage is Ambulocetus (). It looked a bit like a crocodile, I think.
UC Berkeley has a very nice page on the evolution of whales: http://evolution.berkeley.edu/evolibrary/article/evograms_03