New discoveries show how whale diversity exploded after the dinosaurs disappeared
The asteroid that struck the Earth 66 million years ago changed far more than life on land. Ocean ecosystems also collapsed in the aftermath of the strike, and, like the non-avian dinosaurs on land, almost all the impressive marine reptiles that had swum the ancient seas disappeared. Then, as life recovered, the oceans offered possibilities that had not been open for over 180 million years—waters virtually free of large predators. There, early whales could take the evolutionary plunge.
Among the most impressive of these new beasts were the basilosaurids. Named after Basilosaurus, one of the first fossil whales ever discovered, these oceanic carnivores were seagoing success stories. And a pair of recent fossil discoveries underscores how these early whales opened up a variety of niches long before the earliest dolphins or baleen whales would evolve.
