Rhesus Monkey Macaca mulatta

Head and body length is up to 764 mm and tail length is 25 percent of that. Macaca have been found to breed between the species without any compromise to the offspring's fertility. M. mulatta is likely the most adaptable to a wide variety of habitats and elevations, from high heat to snow fields, to cities. These urban areas offer good shelter and abundance of readily available food.

Foraging occurs mainly on the ground, but M. mulatta is arboreal and an excellent swimmer. As are all macaques, M. mulatta is primarily diurnal. Preferred foods include wild and cultivated fruits, berries, grains, leaves, buds, seeds, flowers, and bark.

Most social groups range from 8-180 individuals of both sexes, but there are generally 2-4 times as many females as males. Dominance hierarchy is more evident among small groups of males than those with more females who tend to live together more peacefully than the males. Breeding tends to occur between high ranking individuals. The job of the males is to defend the group, while the females form a small internal subgroup to raise the young macaques whose social status within the troop is inherited from the mother. M. mulatta is highly vocal sounding a shrill bark for alarm, barking or screeching as an aggression response, a scream when under attack, an aggressive growl, and a squawk of surprise.

The gestation period for M. mulatta is 135-194 days and usually one baby is born. Infrequently a set of twins is produced. Babies are nursed for about one year, first clinging to their mother's bellies and later riding on her back. Sexual maturity in females is reached between the ages of 2.5 and 4 years, males 2-3 years after that. Females reach menopause at age 25.

M. mulatta is the sacred monkey of the Hindu religion and is often found in the vicinity of temples. This species has been used extensively in the US for research in the areas of biology, behavior, medicine and even space flight.

M. mulatta is found in Afghanistan and India to N Thailand, China, and Hainan Isl (China).