<human>: What is the most important difference between the hippopotamus and the hyena?
<bot>: The most important difference between a hippopotamus and a hyena is that a hippopotamus is a mammal, while a hyena is a carnivore. Hippos are large mammals with thick, protective skin and can weigh up to 3,500 pounds. Hyenas are smaller than hippos and have pointed canine teeth for tearing meat.