What Are Baboons and Why Do They Have Swollen Bottoms?
Baboons are large, dog-like monkeys which have adapted to a life on the ground, only returning to the trees if attacked. They live in open grassland in family groups called troops, ruled by a big male. They are fierce fighters, and have long canine teeth, close-set eyes; thick fur except on their muzzle; a short tail, which means they don’t use their tail like a hand; and rough spots on their protruding buttocks, called ischial callosities.
These calluses are nerveless, hairless pads of skin that provide for the sitting comfort of the baboon. Living in the forests of West Africa are relatives of the baboon, the drill and mandrill. The nose, cheeks and hind regions of the mandrill are brightly colored red and blue to attract females. When a female baboon is ready to mate, her bottom becomes swollen and red as a sign to the males. Bottom growth has been recorded as much as 6.5 inches (16.5 cm).
Baboons can live up to 30 years in the wild. Female baboons can reproduce even when they get very old, unlike human females. After mating, a baboon female has a gestation period of around six months. Typically, a female will only give birth to one offspring at a time, though twins have been recorded. Baby baboons are called infants. Infants weigh about 2 lbs (1 kg) at birth and cling to their mother by hanging onto her chest fur as she goes throughout her day. They only drink their mother’s milk until they start weaning at 3 to 4 months old. Like with human infants, weaning can be a long process full of tantrums.
A little before a baboon turns 2 years old, it starts becoming a juvenile and grows one pound every three months, according to the Amboseli Baboon Research Project. They become mature at around 6 to 8 years old. Males typically leave their troops when they become adults while the females stay. Males will often join other troops and leave again many times throughout their lives.