Rhinoceroses have evolved large facial horns and thick skin to help protect them from predators and developed broad feet and legs to help support their bulky frames, according to Animal Diversity Web. Additionally, rhinoceros mouths have evolved differently among various species. Those species that are selective feeders have narrow, prehensile lips, while those that graze on grass have broad lips.
In addition to protecting them from predators, male rhinos' horns are used in fights over breeding rights and territory, states Animal Diversity Web, a project of the University of Michigan. Different species of rhinoceroses have different horn arrangements to help the animals survive in their habitats. For example, Indian rhinos have only one horn, which allows them to penetrate their thick forest habitats more easily. In contrast, black rhinos have two large horns, as they inhabit habitats that are more open.
Rhinoceroses are generally solitary animals except during the breeding season. They use dung and urine to communicate with other rhinos. Females generally are passive when they encounter each other, while males often exhibit antagonistic behavior when they encounter other rhinos. Mothers stay with their young for extended periods of time to help protect them from predators.
Rhinoceroses live for about 30 to 35 years in the wild. In captivity, where they have access to plentiful food and need not defend themselves from predators, they can live up to 45 years.