One of the most vulnerable animals on Earth with a likelihood of becoming extinct is the hippopotamus, though their population is about 150,000. They are mostly found on the continent of Africa. Hippopotamus live to between 40 and 50 years. It is a large semi-aquatic mammal that is found wallowing in the rivers and lakes across sub-Saharan Africa. The hippopotamus is most closely related to the whale as they both have a common ancestor that existed about 54 million years ago.
There are two hippo species: The Common Hippopotamus and the Pygmy Hippopotamus. The common hippo is an abundant and widespread species throughout the African continent, but its population is declining due to both hunting and habitat loss. The pygmy hippo lives a solitary forest-dwelling life and is found in western Africa.
At one time, the hippopotamus was found across Europe and Asia but are now confined to Africa south of the Sahara Desert. They almost always gather near water and tend to prefer areas close to grasslands where they feed during the night.
Hippos have huge grey barrel-shaped bodies that can measure more than 16 feet in length and weigh more than 4 tons or over 8,000 pounds. Their bodies are held up by short and stocky legs. One of the most unique and interesting features of the hippo is their large jaws which contain a couple of long canine teeth called tusks which can grow over 18 inches long. The tusks are also used for fighting.
In addition, since the hippo often spends much of its life wading in water, they have several adaptations to help them maneuver through the lakes and rivers of their habitats. They have four webbed toes on each foot that help with swimming and walking on the slippery banks. Their eyes, ears, and nostrils are situated on top of their head, so when the Hippopotamus's body is immersed in the water, they are still able to see, hear and breath while keeping cool in the hot sun.
They spend up to 18 hours a day in the water to keep cool, but at night, they travel onto land and follow paths to their feeding grounds, and later in the morning, return to the water. The hippo is one of the largest and most feared animals in Africa as both the males and females are known to be extremely aggressive at times. They usually live in small herds containing between 10 and 20 individuals that include females with their young.
The herd is led by a dominant male hippo who fiercely guards his stretch of river bank against intruders and rival males. The hippo uses and opens his enormous mouth to expose the long tusks. If the lead male cannot scare off another male, the two will fight often resulting in deadly injuries. Although at times, the dominant male will permit other males to enter the territory, they must be well-behaved as he holds the breeding rights with the females in the herd.
Female hippos give birth to a single calf during the rainy season following an 8-month gestation period. The hippopotamus often gives birth in the water but sometimes the young are born on land. The female protects her calf fiercely and it rides on her back to keep it safe. Hippopotamus calves are fully weaned by the time they are 18 months old but tend to remain with their mother until they are fully grown, often not leaving her until they are 7 or 8 years old.
Although young males will become more independent and find their own patch of the bank to patrol, females will join a herd of other females and young but despite this seemingly sociable behavior, they do not seem to interact socially and will even graze on their own when they leave the water at night.
The hippopotamus is an herbivorous animal surviving on a vegetarian diet despite their long and sharp teeth. Grasses are their main source of food. The Hippopotamus has strong lips that are used to clip the grasses and cheek teeth which then grind them up. Despite its large size, the Hippopotamus only eats around 88 pounds of food at night as it uses very little energy while floating in the water for most of the day. The hippopotamus is a unique animal, and despite its large size, the hippo is much faster than most people realize, and it can run at speeds of up to 30 miles per hour.