Imagine standing on a muddy riverbank 50 million years ago and seeing a strange creature lumbering by—part crocodile, part ...

Another, slightly more recent form, called Ambulocetus ... "In one sense, evolution didn't invent anything new with whales. It was just tinkering with land mammals. It's using the old to make ...

Whales, the ocean's largest creatures ... Pakicetus' descendants continued to adapt, leading to the evolution of Ambulocetus, which lived between 50 and 48 million years ago.

As their descendants continued to adapt to life in water, the cetacean lineage led to species like Ambulocetus, which lived between 50 and 48 million years ago. Today, whales are divided into two ...