Hippopotamuses are creatures that inhabit the Pride Lands.
In Real Life
The hippopotamus (meaning "river horse") is a large, mostly herbivorous mammal. After the elephant and rhinoceros, the hippopotamus is the third largest land mammal. The hippopotamus is semi-aquatic, inhabiting rivers, lakes and mangrove swamps. Hippos spend most of their days wallowing in the water or the mud, with the other members of their pod.
The water serves to keep their body temperature down, and to keep their skin from drying out. With the exception of eating, most of hippopotamuses' lives —from childbirth, fighting with other hippos, to reproduction— occur in the water. Hippos leave the water at dusk and travel inland, sometimes up to 8 kilometers (5 mi), to graze on short grass, their main source of food. The hippo's proportions reflect its sedentary, amphibious existence. Its plump and bulky body is set on short, stumpy legs, with each foot having four toes.
Their chief predators are poachers, who may hunt hippos for their meat, hides and ivory teeth.
In The Lion King films
In The Lion King, hippopotamuses appear briefly at the end of The Circle of Life and when Simba sings I Just Can't Wait to be King. They along with other various animals help Simba and Nala lose Zazu. They later appear at the end of the movie during the presentation of Simba's newborn cub.
In The Lion King II: Simba's Pride, they are seen during Kiara's presentation, We Are One, and Upendi. They also appear driving Kovu out, when Simba exiles him from the Pride Lands, and later at the end of the movie.
In The Lion King 1½, hippopotamuses appear when Timon and Pumbaa find Pride Rock. The hippopotamuses were attending the presentation of Simba, one of the hippos collapsed with many other animals when Pumbaa becomes a victim of his demophobia-triggered flatulence problem. Later, some hippos are seen when Timon and Pumbaa are disturbed by some noise from outside, which is actually Simba, Nala and the animals singing "I Just Can't Wait to Be King" while making an animal pyramid with many other animals like the original film.
Zazu reports to Simba about how the hippopotamuses are fighting with the other Pridelanders over the water hole.
In the midst of a flood, Timon is nearly swallowed by a hippopotamus.
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