Macaques are medium-size monkeys with stout bodies and strong limbs. There are about 20 species in five families and 40 different and subspecies and they range across from the Atlantic to the Pacific but are found mostly in Southeast Asia, Indonesia and India. Forests and mountains have been their traditional habitat but many now live in cities (See Urban Monkeys).
"The macaque is one of the most successful and versatile of all primates,”David Attenborough wrote. “If you wanted to pick a monkey that was bright, adaptable, versatile, resilient, enterprising, tough and capable of surviving in extreme conditions and taking on all comers, the macaque would win hands down.” The do equally well in mountains. marshes, rain forests and cities.
Macaques are relatives of guenons. There are 15 species, including rhesus monkeys.
Macaques can be found in Spain, Morocco, Afghanistan India, South Asia, Sri Lanka, Indonesia, Tibet, Southeast Asia, Japan.
Macaques have a larger brain than other monkeys. This gives them the mental capacity to move their hands and fingers with almost human dexterity and provides them with sophisticated hand to eye coordination. Most species are brownish or greyish in color. Males are generally 50 percent heavier than females.
Macaques generally have short tails, ranging from one centimeter to 25 percent of their head and body length. A few species have tails longer than their body and head. Many spend most of its time on the ground and has little use of their tail. On macaque tails, David Attenborough wrote: “It is not prehensile like that of South American monkeys, and they hardly need it for balancing on the ground. To some extent it is used in signaling, but in cold weather, it can be a real liability. For such long extremities lose a lot of heat and are susceptible to frost bite. So the tails of macaques have either been greatly reduced or completely lost. The Indonesian species, which clambers around mangrove swamps, feeding on crabs, still has a respectably-sized tail. Another, that has a wide distribution from India to Vietnam, has a reduced tail and is known, perfectly accurately as the stump-tailed macaque. The Moroccan species however has lost its tail completely and this has led to it being given a highly inaccurate name. It is sometimes called the “Barbary “ape.”
Macaques have the characteristics of fruit-eating monkeys. Some macaques are good swimmers. Hanging out in mangrove swamps, crab-eating macaques search and dive for crabs and other crustaceans. They can break open mollusks and tear apart crustaceans.
Most macaques are diurnal. Although they are comfortable in trees they chose to spend their time on the ground. Some species spend most of their time in the trees. Others spend most of their time on the ground. Most sleep in the trees at night and forage on the ground during the day and forage for food from there.
Most macaques feed on wild and cultivated fruit, berries, grains, leaves, seeds, flowers and bark. All species from time to time eat insects, worms and small invertebrates and occasionally take eggs and small vertebrates.
Many macaques have similar vocalizations: shrill barks for alarm, a growl for aggression, a squawk for surprise and screeching as a response to aggression. Macaques like to groom so much they do it to other species such langur monkeys and even deer and squirrels
Macaque Group Behavior
Many macaques hang out in large troops that sleep together in the same tree, forage for food in the morning and evening and rest in the afternoon. A typical group has a male leader, a core group of females and their young and a peripheral group of younger males and maybe some young females. Within this structure are hierarchal rankings based on sex, age, kin ship and alliances. In some cases only high ranking males and females mate and the status of young macaques is based on the rankings of their mothers.
Groups can have between four to a hundred members. Generally there are two to four times as many females as males Females usually remain in the groups they are born in and have a rigid hierarchy while males usually change groups. In some groups males are dominant. In some females are. In other groups both males and females are. Whatever the case females tend to get along well together while males range from peaceful to hostile
Males often live alone or live in small groups on their own. Among bonnet macaques, males of all ages often form subgroups and bond with and groom one another. Among rhesus macaques males usually avoid one other or are hostile. Other macaques display in-between behavior. Female macaques sometimes abuse their children. Male Barbary macaques steal infants and hold them in ransom for higher social status.
Macaque Reproductive Behavior
Female macaques generally reach sexual maturity when they are around five and are able to continue giving birth until they are 18.
Many macaque species have a specific breeding season, often between February and May and to a lesser extent in September or October. Females often signal they are in estrus when their genital area becomes red. Estrus usually lasts about nine days. The gestation period is between four months to seven months. Usually only a single young is born.
Young macaques may nurse for up to a year They often cling to their mother’s belly when they are very young and then ride on their mother’s back when they get older.
There are 20 species of macaque in five species groups. Many have monkey in their name rather than macaque. There is a debate among scientists as to which macaques are true species and which are not. Many species are capable of breeding with other species and their offspring are fertile. In some place they do interbreed, producing hybrids and crossbreeds.
Well known macaque species include Japanese snow monkeys, rhesus monkeys in India, the Barbary Ape of southern Spain, the Celebes ape of Sulawesi, the crab-eating macaque of Southeast Asia, the liontail macaque of India, the pigtail macaque of Southeast Asia, the toque macaque of Sri Lanka , and the bonnet macaque of India.
Eight species live on the Indonesian island of Sulawesi or the islands around it. There is some debate though as to whether they are really different species. Six species of macaque live in India.
Some species are endangered due to logging, deforestation, loss of habitat, killing as pests and food, and capture for pets and research. The Mentawai macaque is critically endangered. The lion-tailed macaque and Sulawesi black macaque are endangered. In south India, the meat of the lion-tailed macaque is believed to be an aphrodisiac and have other medicinal qualities. In China macaque flesh is taken as a malaria treatment and a cure for lassitude
Pig Tailed Macaques
Pig-tailed macaques are relatively large, russet, rain forest monkeys native to Southeast Asia. Males can measure up to two feet from the buttocks to the top of the head and weigh up to 40 pounds. When threatened they screech and bare their canines. The buttocks of females become swollen and red when they are receptive to mating.
Pig-tailed macaques are regarded as "clever, political animals" with "good mother-infant bonding and particularly strong peer interaction and play." Their thick fur protects them from bees and stinging ants. In some parts of Malaysia, pig-tailed macaques are used to pick coconuts.
Crab-eating macaques feed on crabs, other crustaceans and other animals exposed by low tide. They are usually unsuccessful in efforts to chase crabs but are able to catch them when the they wait at the crab’s hole and grab when it emerges to take a look. These monkeys have been observed getting pinched by a crab and frantically flapping their hands in the air.
Rhesus monkeys are a kind of macaque native to northern India and Pakistan. They can adapt to almost any environment. They streak through bazaars, walk through snow and are as comfortable in city streets as they are in the forest. They often live around temples and are regarded as sacred.
Rhesus monkeys are the commonest monkeys in India. They make up most of India’s 1.5 million monkeys. About half of them live in urban areas.
Most of the troublesome monkeys in India are Rhesus monkeys. See Monkey Attacks
Rhesus monkeys have been extensively studied by Alison Richard of Yale.
Rhesus Monkey Behavior
Rhesus monkeys live in matriarchal societies, with mothers ranking above their daughters (and supporting them in fights) until they are very old. There is also a hierarchy of matriarchal units that is determined by relations between dominant female in each group. The situation in which family members will come to the aid of a female or not are usually defined by the ranking of the adversary. Rankings are sometime dramatically altered when females are claimed by disease or predators.
Male rhesus monkeys migrate between troops when they are young. Their status depends on their support from female members of their troop and their rank among males is derived from their fighting ability. Rhesus monkeys accept mentally retarded members to their group as they would a normal animal.
Rhesus monkeys can be very aggressive. Individuals often have missing ears, slashed faces and finger stumps that have resulted from fights and bites. When rhesus monkeys are involved in a threatening exchange they usually scream and screech and then look around to see who can support them. Fights between males can be quite nasty. One male was observed biting off the testicle of a rival, who in turn was observed mating the following day.
Young female rhesus monkeys have three main support calls: 1) a noisy blurred scream used when threatened by a dominant female; 2) a scream with a rising and falling pitch used when threatened by a subordinate; 3) a tonal, pulsed scream used when threatened by a member of the same matriarchal unit. Urgency is usually determined by the loudness and length of the calls. Mothers often respond to only the most distressed calls (unlike human mothers who often can't tell if their babies have a small or severe problem and respond equally in all in most cases).
Rhesus Monkeys and Research
Rhesus monkeys were once the most common laboratory primate. In the 1950s, India was exporting 200,000 of these animals a year to Europe and the United States for biomedical research alone. For a number of reasons, the export was banned in 1978 and long-tailed macaques are now the most commonly used primate in medical research.
Scientists use rhesus monkeys to study HIV/AIDS drugs, research vaccines for rabies, smallpox and polio, and to study potential uses for embryonic stem cells. They have also been launched into space on test missions by the US and Russia.
Rhesus monkeys were used in pioneering studies of human blood. The Rh factor is named after them. A rhesus monkey has been genetically engineered to have jellyfish DNA in every one of its cells. The manipulation was done as step towards genetically manipulating human cells to fight disease. They are also widely exhibited at circuses and zoos and are a favorite of street performers with monkey acts.
In India, populations of rhesus monkeys have risen and fallen in respect to the attitudes of locals towards the animals. In the 1940s, when they were still revered as sacred animals there were an estimated 40 million of them. In the 1960s and 70s when they were preconceived as pest their numbers dropped to around 200,000. Now there are believed to be around a half million of them, with 85 percent of them living around people.
Many monkeys used in laboratory work originate in China.
Troublesome Urban Monkeys
Monkeys are as common as squirrels in some Asian cities, particularly in India, Thailand, Sri Lanka and Indonesia. They hang beside roads in the country and squat in the shade in train stations. Most are macaques (rhesus monkeys) and many are regarded as pests. They raid trash cans, steal ice cream cones from children, climb around on telephone and electric wires. Sometimes they get electrocuted when they touch frayed electric lines.
The monkeys often use temples as their home base because there they are protected and often fed and pampered. From the temples they radiate out. In the past many lived at temples with nearby forest in which they could retreat but now these temples have been swallowed up by urbanization and the only place they go is into the city.
"Once they get into human habited areas, initially they are shy," one monkey authority told AFP. "At that time people make the mistake of feeding the monkeys. Monkey's being smart, they soon give up their shyness and start demanding food. When they do that people don't take to them anymore. So the monkeys start entering houses, start opening refrigerators and take away food.”
Monkeys like urban areas because they have easy access to shelter, large trees, abundant food and water. In some cities their populations have exploded because the monkeys can get a hold of enough food to support such a large population. In some places the monkey are seriously obese. In other places their population are more stable apparently because their numbers are kept in check by disease and a limited food supply.
Monkeys run wild in Delhi. They make trouble by breaking into homes, stealing food from refrigerators, taking clothes off drying lines, damaging television antennas, making loud noises and destroying property. Sometimes they attack pedestrians. They like to break into offices at night and search through files for food. Monkey have even broken into the Presidential Palace and the defense ministry, destroying and stealing files. On his visit to the Amber Fort in Delhi, U.S. President Bill Clinton was ambushed by a bunch of monkeys. He discovered later they were attracted by his flower lei. "Once I deflowered they weren't interested in me," he said.
Image Sources: Wikimedia Commons
Text Sources: National Geographic, Natural History magazine, Smithsonian magazine, Wikipedia, New York Times, Washington Post, Los Angeles Times, Times of London, The Guardian, Top Secret Animal Attack Files website, The New Yorker, Time, Newsweek, Reuters, AP, AFP, The Economist, BBC, and various books and other publications.
Last updated November 2012