EOCENE SEAS

This large mural is an artist’s depiction of early whales that lived during the Eocene time period (56 to 34 million years ago). The top whale is Basilosaurus. At up to 60 feet long and 50-75 tons, it is one of the largest creatures of the Eocene, rivaling earlier, landbound sauropod dinosaurs in size. Basilosaurus had small flippers and a short head with a narrow snout and probably swam by undulating its long, snake-like body. It is in roughly the same weight as the monster shark Megalodon, which lived 10 million years later.”

The middle whale is likely a Dorudon. At 16 feet long and half a ton with small distinctive teeth, this short, stubby cetacean may actually have been preyed on by the occasional hungry Basilosaurus. (This scenario was reenacted by the BBC nature show Walking with Beasts, which showed Dorudon juveniles being gobbled up by their larger cousins).”

The bottom whale is likely Zygorhiza, about 20 feet long and one ton. The skeletons of Zygorhiza show a larger rib cage than Basilosaurus, but a similar mouth full of teeth with a long, narrow body and long head. “Zygorhiza’s front flippers were hinged at the elbows, a hint that this prehistoric whale may have lumbered up onto land to give birth to its young."

Text compiled from Linda Hand (College of San Mateo) and Bob Strauss (About.com)
Artist: unknown (painted in 1990)
Mural’s original location: California Academy of Sciences — Life Through Time Exhibit