The creatures cruised the world’s oceans with features we often associate with marine mammals, such as coats of blubber and ...

Non-bird dinosaurs lived between about 245 and 66 million years ago, in a time known as the Mesozoic Era. This was many millions of years before the first modern humans, Homo sapiens, appeared.

sharks and mammalian ancestors from the Mesozoic era. The data will help us answer crucial questions about mass extinctions and how species were distributed across our nation millions of years ago.