Walking With Beasts - Ep 2 Whale Killer (2001) [576p]

The mass extinction event that saw the demise of the dinosaurs was almost as devastating in the seas. The oceans were emptied of almost all large animals and carnivorous creatures, leaving them ripe for exploitation by new predators. 30 million years after the dinosaurs, the top of the ocean food chain is now occupied by an early whale: Basilosaurus. As on land, it's the mammals that have replaced the giant reptiles as the ultimate marine predators and none can now match the Basilosaurus.