MACAQUES: CHARACTERISTICS, BEHAVIOUR, MATING

MACAQUES

Barbary Macaque

Macaques are medium-size monkeys with stout bodies and strong limbs. There are 23 species in five families and 40 different subspecies. They range across from the Old World from the Atlantic to the Pacific, including Spain, Morocco, Afghanistan Sri Lanka, Tibet, and Japan, but are found mostly in Southeast Asia, Indonesia and India. Forests and mountains have been their traditional habitat but many now live in cities.

Aside from humans, macaques are the most widespread primate genus. By some estimates, in evolutionary terms, the primate line that produced humans separated from macaque line about 25 million years ago. "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.” They do equally well in mountains. marshes, rain forests and cities.

Macaques constitute the genus (Macaca) of gregarious Old World monkeys of the subfamily Cercopithecinae. Relatives of guenons, they are primarily frugivorous (preferring fruit), although their diet also includes seeds, leaves, flowers, and tree bark. Some species such as the long-tailed macaque, also called the crab-eating macaque, supplement their diets with small amounts of meat from shellfish, insects, and small mammals. On average, a southern pig-tailed macaque in Malaysia eats about 70 large rats each year. All macaque social groups are arranged around dominant matriarchs. [Source: Wikipedia]

Macaques are popular zoo animals. They are also useful in biological, medicinal, and psychological research because of their similarity to humans in physiology and disease susceptibility. They are sometimes hunted for food. Certain diseases can be transmitted between humans and macaques. There is evidence of macaque exposure to human respiratory viruses, including influenza A and parainfluenza 1, 2, and 3. This anthropozoonotic exchange may occur through individuals kept as pets, which come into contact with both wild macaques and humans. [Source: Rae Ellen Bichell, Animal Diversity Web (ADW)]

Websites and Resources: Animal Diversity Web animaldiversity.org ; BBC Earth bbcearth.com; A-Z-Animals.com a-z-animals.com; Live Science Animals livescience.com; Animal Info animalinfo.org ; World Wildlife Fund (WWF) worldwildlife.org the world’s largest independent conservation body; National Geographic National Geographic ; Endangered Animals (IUCN Red List of Threatened Species) iucnredlist.org

Macaque Characteristics

Macaques are robust primates whose arms and legs are about the same in length. Their muzzles are rounded in profile with nostrils on the upper surface. 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, blackish or greyish in color. Males are generally 50 percent heavier than females.

The monkey's size differs depending on sex and species. Males from all species can range from 41 to 70 centimeters (16 to 28 inches) in head and body length, and in weight from 5.5 to 18 (12.13 to 39.7 pounds). Females can range from a weight of 2.4 to 13 kilograms (5.3 to 28.7 pounds). In some species, skin folds join the second through fifth toes, almost reaching the first metatarsal joint. [Source: Wikipedia]

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 have little use for their tail. Although several species lack tails, and their common names refer to them as apes, these are true monkeys, with no greater relationship to the true apes than any other Old World monkeys.

Formosan macaque

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 spend most of their time on the ground and spend some time in trees. They have large pouches in their cheeks where they carry extra food. These cheek pouches allow the macaques to gather food quickly when they are the ground in case predators are around and take the stored food up into the trees where it is safer and the animals can consumer their food at a comfortable pace. 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.

Macaque Behavior

Macaques are considered highly intelligent and are often used in the medical field for experimentation due to their remarkable similarity to humans in emotional and cognitive development. These primates live in troops that vary in size, where males dominate, however the order of dominance frequently shifts. Female dominance lasts longer and depends upon their genealogical position. Macaques communicate and sense with vision, touch, sound and chemicals usually detected by smelling. Communication in all monkeys involves a variety of visual signals (such as body postures and facial expression), tactile communication (such as grooming, playing and fighting), vocalizations, and scent cues.

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.

Macaques use a combination of visual (facial expression, body postures), auditory (vocalizations), physical (grooming, play, mating, aggression) and possible chemical (olfactory) signals as ways to communicate. They have extensive patterns of communication, typical of diurnal (active during the daytime), primates. They rely heavily on vocal communication. 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 Reproduction

For macaques rate of growth and sexual maturation depends upon feeding and social conditions. In general females reach sexual maturity around three years old, typically giving birth to their first offspring at age one. Male puberty begins at age three with full testicular enlargement at age four to five. Gestation averages 24 weeks and the female gives birth to one infant. Infants nurse their mothers until six to seven months old. The average time between births is one to two years. Female reproductive lifespan produces on average five offspring before they undergo menopause around 27 years old. [Source: Monica Brown, Animal Diversity Web (ADW)]

In most macaques, females can reproduce once per year if conditions are good. Young are weaned before they reach one year of age. However, the reproductive potential of each species differs. Populations of the rhesus macaque can grow at rates of 10 percent to 15 percent per year if the environmental conditions are favorable. However, some forest-dwelling species are endangered with much lower reproductive rates. 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. After one year of age, macaques move from being dependent on their mother during infancy, to the juvenile stage, where they begin to associate more with other juveniles through rough tumble and playing activities. Young are typically independent after about two years, although may retain life-long associations with their mother.

Macaques sexually mature between three and five years of age. Female macaques can continue giving birth until they are 18.Females will usually stay with the social group in which they were born; however, young adult males tend to disperse and attempt to enter other social groups. Not all males succeed in joining other groups and may become solitary, attempting to join other social groups for many years. [Source: Wikipedia]

Macaque Species

lion-tailed macaque

As we said before there are 23 species of macaque. Some like the rhesus monkey 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

‘Monkey Archaeology’ Uncovers Macaque’s Stone Age Culture

The world’s first archaeology dig of an old world monkey culture has uncovered tools used by previous generations. The discovery, reported in June 2016 in the Journal of Human Evolution, means humans aren’t unique in leaving a record of our past culture that can be examined open through archaeology. [Source: Alex Kasprak, New Scientist, June 10, 2016]

Alex Kasprak wrote in New Scientist:“Burmese long-tailed macaques are renowned for their use of stone tools to crack open shellfish, crabs and nuts, making them one of the very few primates that have followed hominins into the Stone Age. “Now, for the first time, researchers have carried out a successful “monkey archaeology” dig to begin studying the origins of the behaviour. “It’s a very clever idea and it’s something that was waiting to be done,” says Michael Huffman at Kyoto University in Japan, a primatologist who studies rock handling behaviour in Japanese macaques. “It just took someone to go out and do it.”

“Michael Haslam of the University of Oxford and his team conducted their dig on the small island of Piak Nam Yai in Thailand, one of the islands where these monkeys live and use stone tools. They dug through the sandy sediments at the site and found 10 stone tools attributed to macaques, based on their wear patterns. “By dating the oyster shells found in the same sediment layers, they determined the tools could be as old as 65 years, going back two macaque generation.

“We know from eyewitness accounts that these monkeys have been using tools for at least 120 years, so the study doesn’t push the age of the behaviour back. But Haslam sees it as a first step towards digging deeper into the origins of the behaviour. Exactly how far back in time the macaque’s Stone Age extends is anyone’s guess. A rare “chimpanzee archaeology” dig a decade ago showed this ape has been using stone tools for more than 4000 years.

“A long record of ancient stone tools could tell us if the monkeys picked up tool use in response to an environmental stress, such as rapid sea level changes, for example. And it might even show how the practice may have been transferred between different island populations. Just 150 years ago, archaeologists’ claims about early human stone tools were met with scepticism, Haslam says. Since then, scientists have created a detailed and incremental record that shows how hominin stone technologically advanced over millions of years of innovation. “We’re at year zero for the primate world,” he says. It may one day be possible to address questions about how and why tool use arises in animal populations, and about the extent to which that kind of behaviour is — or isn’t — uniquely human, he adds.

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Text Sources: Animal Diversity Web animaldiversity.org ; National Geographic, Live Science, Natural History magazine, David Attenborough books, New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Discover magazine, The New Yorker, Time, Reuters, Associated Press, AFP, Lonely Planet Guides, Wikipedia, The Guardian, Top Secret Animal Attack Files website and various books and other publications.

Last updated December 2024