Hippo Evolution

  • Mesonychiad

    The Mesonychia!
    60,000,000 years ago, Mesozoic era
    Land animal with a long tail and caniverous teeth
    Early mesonychids had five digits on their feet, but later mesonychids had four digits that ended in tiny hoofs. The hooves were nessicary as they supported the weight of the animal, and they provided extra speed for predation.
  • Pakicetus

    The Pakicetus!
    53,000,000 years ago, Cenozoic era, Paleogene Period
    The Pakicetus was semiaquatic, diving after fish as food. However, it was mainly still an land creature because its ears weren't well adapted to hearing well underwater. The ability to hunt in water was significant because it had expanded it's territories to include water. More huntung ground = more food.
  • Indohyus

    48,000,000 years ago, Paleogene Period, Eocene epoch The Indohyus is smaller than the Pakicetus, roughly the size of a racoon instead of a wolf. This may have made semi-aquatic life more manageable, as it would improve mobility between water and land and ensure quick drying with less surface area. A thick outer coat would keep the Indohyus warm in the water. Expecially dense bones, similar to those of the modern hippo, would help reduce bouyancy, allowing the Indohyus to remain underwater.
  • Anthracotherium

    Oligocene period, 34 million to 23 million years ago The lower jaw of the Anthracotherium was very similar to the jaw of the modern day hippo, which demonstrates the similar food sources it and the mondern day hippo enjoy. The tail has also decreased in size. The Anthracotherium doesn't need the extra stability, with its solid body, so the tail has been shortened.
  • Modern Hippos

    Modern Hippos
    Modern Day Red oily secretions help protect the hippo from the sun, as well as mosquitos and other insects, allowing it to remain in the water uncovered for extended periods of time. Eyes and nostrils on top of the head allow the hippo to submerge almost entirely while still hearing and breathing. When the hippo does fully submerge, its ears and nose automatically seal. Special nerves in the jaw bone allow the hippo to sense vibrations underwater, alerting it to nearby threats.