Lions range the African savannah in prides which comprise of related females, their offspring and one individual male. Once a male reaches adulthood it is cast out from the pride and must look for its own group. Lionesses hunt in a team. Together they can overcome large prey such as zebras, buffalos, giraffes, hippos and even young elephants, but they are not averse to eating the remains of other animals' meals. Lions sleep up to twenty hours a day and both males and females defend their pride against intruders. The roar of a lion is very loud and audible up to a distance of eight kilometers. Lions roar in order to communicate with one another and to frighten intruders. The male and female have light brown fur. The males have thick brown manes which grow longer and darker the older they get. Lions live in a pride which is led by a strong male. Usually the females hunt gnus and antilopes together.