genitals and taste their urine. The gestational period is 186 days; births can occur at any time of year. The infant's fur is silver at birth, but turns pale or gold after a few days. After that, the fur starts to darken, and the infant takes on the adult coloration at about 3 months old. The infant is carried under its mother, clinging to its mother's chest, for the first 2 or 3 weeks of its life. After that, it is carried on its mother's back. At about 3 months the mother will usually start to push the infant off, but will still carry the infant some of the time until it is 4 or 5 months old. After the young can move on its own, the mother will carry it across difficult gaps in the trees. Juveniles play among themselves much of the time. Infants are weaned at years old at which point maternal care ends. Adult females typically give birth every 19 to 23 months, assuming the prior infant survived to weaning. The mantled howler differs from other howler monkey species in that the males' testes do not descend until they reach sexual maturity. Upon reaching sexual maturity, the young monkeys are usually evicted from their natal group, although the offspring of a high-ranking female may get to stay in its natal group. However, many infants do not reach sexual maturity; high-ranking adults sometimes harass or kill the offspring of lower-ranking monkeys to eliminate competition to their own offspring for an opportunity to remain with the group upon reaching maturity. Natal emigration is performed by both sexes, with 79% of all males and 96% of the females leaving their original social group. When a male from outside the group ousts the previous alpha male, he normally kills any infants so that the mothers come into estrus quickly and are able to mate with him. Predators, such as cats, weasels, snakes and eagles, also kill infants. As a result, only about 30% of mantled howler infants live more than one year. The highest reproductive success occurs in the middle-ranking females, with the alpha position lower possibly because of competitive pressures, and infant mortality appears to be lower when the timing of births in a group of females is clustered. If it survives infancy, the mantled howler's lifespan is typically 25 years. Distribution and habitat The mantled howler is native