The document summarizes key facts about hippopotamuses. It states that hippopotamuses can grow up to 4.57 meters long and weigh up to 3,600 kg, with a typical lifespan of 20-40 years. They are herbivorous and graze on up to 60 kg of vegetation per night. Hippopotamuses live in Southern Africa and near the Nile River. Their populations are decreasing in most countries, though increasing in Congo and Zambia. Females give birth after 6-8 month gestation and calves can walk within 5 minutes of birth. Calves face predation from lions and hyenas, while adults have no natural predators due to their large size.