Basilosaurids like Chrysocetus, Dorudon, and Basilosaurus ruled the seas of the late Eocene, occupying ecological roles much like today’s dolphins and orcas.
Basilosaurus grew into a serpent-like giant over 15 meters long, while Dorudon was smaller, sleeker, and likely faster. Chrysocetus was somewhere in between—mid-sized, streamlined, and adapted for powerful undulating swimming.
These early whales represent a pivotal stage in cetacean evolution. They bridge the gap between the land-dwelling artiodactyl ancestors (even-toed ungulates like deer and hippos) and the fully marine mysticetes (baleen whales) and odontocetes (toothed whales) that would later diversify in the Oligocene.
Looking at their remains, we are seeing a window into our world when whales were still learning to be whales—a fleeting evolutionary moment preserved in Moroccan stone, where golden bones tell the story of an ocean in transition.
