Zygorhiza kochii
Information
Zygorhiza kochii lived in the shallow coastal seas of what is now Mississippi, alongside fishes and invertebrates, many of which still exist. These early whales retained the hind limb of their land-based (terrestrial) ancestors, modified as a small flipper. This was later lost in the evolutionary history of whales.
Growing to 6 m in length, this fossil whale was a formidable predator. Unlike modern 'toothed whales', the teeth of Zygorhiza had different shapes along the jaw, a relict feature of their terrestrial ancestry.
Location: Mississippi, USA
Age: Late Eocene (35 million years ago)