The hippopotamus, commonly referred to simply as the hippo, is a large animal that is native to the sub-Saharan region of Africa. The hippo is often considered to be the third largest land animal, smaller than only the rhinoceros and the elephant. The word hippo is derived from the Ancient Greek term for "river horse." Hippos have several distinct features such as massive barrel-like torsos, the lack of hair on their body, and huge canine tusks. Despite a striking resemblance to pigs, the closest evolutionary relatives to hippos are cetaceans such as dolphins, porpoises, and whales. Hippos often live near lakes, rivers, and swamps, where they lead a semi-aquatic life that significantly influences their diet.
Diet of Hippos in the Wild
In the wild, hippos spend much of their time in the water, coming out at around dusk to feed mainly on the short grass that surrounds their habitat. In order to find a sufficient amount of food, hippos may travel long distances, which can exceed 6 miles. Hippos consume large quantities of grass on a daily basis, with some estimates suggesting that they can eat up to 150 pounds in a single night. Although hippos live in the water, they consume small quantities of aquatic plants. In the wild, hippos may also feed on available fruits.
Diet of Hippos in Captivity
Hippos are kept in confinement all over the world in zoos such as the San Diego Zoo, the Toledo Zoo, and the London Zoo. In most cases, these zoos are situated far from the hippo's native habitat, which dramatically influences the food that the hippos can consume. Some of the items that hippos in captivity feed on include hay, lettuce, and vegetables. Captive hippos may be given treats such as melons and other fruits in special instances. Zoos also often feed hippos vegetarian pellets to supplement their nutritional requirements.
Do Hippos Eat Meat?
Although hippos are herbivores, there are several instances in which they have been recorded eating meat and engaging in cannibalism. The first verified instance of hippos eating meat was recorded in 1995 by Dr. Joseph Dudley (University of Alaska) while visiting the Hwange National Park in Zimbabwe. According to Dr. Keith Eltringham, one of the world's leading experts on the species, hippos may consume meat because of insufficient nutrients.
Feeding Adaptations of the Hippo
Since they primarily feed on grass, hippos have developed many unique evolutionary adaptations to improve their feeding. Some adaptations include well-developed lips, which they use to pull up the grass and massive teeth primarily used to cut the grass before they swallowing. Another major adaptation of the hippo is a long alimentary canal to reduce the speed of digestion, which increases the time that the hippo has to absorb vital nutrients. Hippos can keep food in their stomach for long periods of time, but do not chew the cud. Hippos also have well-developed senses, particularly their hearing which allows them to hear fruits falling, and their sense of smell, which helps them to find food.