The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories,
is a
cercopithecine
The Cercopithecinae are a subfamily of the Old World monkeys, which comprises roughly 71 species, including the baboons, the macaques, and the vervet monkeys. Most cercopithecine monkeys are limited to sub-Saharan Africa, although the macaques ...
primate
Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians (monkeys and apes, the latter including huma ...
native to
Southeast Asia
Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...
. A species of
macaque, the crab-eating macaque has a long history alongside humans.
The species has been alternately seen as an agricultural
pest,
a sacred animal,
and, more recently, the subject of medical experiments.
The crab-eating macaque lives in
matrilineal
Matrilineality is the tracing of kinship through the female line. It may also correlate with a social system in which each person is identified with their matriline – their mother's Lineage (anthropology), lineage – and which can in ...
social groups of up to eight individuals dominated by females.
Male members leave the group when they reach
puberty
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a boy. ...
.
It is an opportunistic
omnivore
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutr ...
and has been documented using tools to obtain food in
Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...
and
Myanmar
Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John C. Wells, Joh ...
.
The crab-eating macaque is a known
invasive species
An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...
and a threat to
biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') l ...
in several locations, including
Hong Kong
Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delt ...
and western
New Guinea
New Guinea (; Hiri Motu
Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea).
It is a simplified version of ...
.
The significant overlap in macaque and human living space has resulted in greater
habitat loss
Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
,
synanthropic
A synanthrope (from the Greek σύν ''syn'', "together with" + ἄνθρωπος ''anthropos'', "man") is a member of a species of wild animal or plant that lives near, and benefits from, an association with human beings and the somewhat artific ...
living, and inter- and intraspecies conflicts over resources.
Etymology
''Macaca'' comes from the Portuguese word ''macaco'', which was derived from ''makaku'', a word in
Ibinda
Ibinda (also ''Kibinda'', ''Chibinda'', ''Tchibinda'', ''Cibinda'') is ostensibly a Bantu language or a dialect group spoken in the Angolan province and exclave of Cabinda.
Ibinda is Western Kongo ( Guthrie: H16d) as it is spoken in Cabinda. ...
, a language of
Central Africa
Central Africa is a subregion of the African continent comprising various countries according to different definitions. Angola, Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo, ...
(''kaku'' means monkey in Ibinda).
The specific epithet ''fascicularis'' is Latin for a small band or stripe.
Sir Thomas Raffles
Sir Thomas Stamford Bingley Raffles (5 July 1781 – 5 July 1826) was a British wikt:statesman, statesman who served as the Lieutenant-Governor of the Dutch East Indies between 1811 and 1816, and Lieutenant-Governor of Bencoolen between 1818 a ...
, who gave the animal its scientific name in 1821, did not specify what he meant by the use of this word.
In Indonesia and Malaysia, ''M. fascicularis'' and other macaque species are known generically as ''kera'', possibly because of their high-pitched cries.
The crab-eating macaque has several common names. It is often referred to as the long-tailed macaque due to its tail, which is often longer than its body.
The name crab-eating macaque refers to its being often seen foraging
beach
A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shel ...
es for crabs. Another common name for ''M. fascicularis'' is the cynomolgus monkey, from the name of a race of humans with long hair and handsome beards who used dogs for hunting according to
Aristophanes of Byzantium
__NOTOC__
Aristophanes of Byzantium ( grc-gre, Ἀριστοφάνης ὁ Βυζάντιος ; BC) was a Hellenistic Greek scholar, critic and grammarian, particularly renowned for his work in Homeric scholarship, but also for work on other ...
, who seemingly derived the etymology of the word ''cynomolgus'' from the Greek κύων, ''cyon'' 'dog' (gen. ''cyno-s'') and the verb ἀμέλγειν, ''amelgein'' 'to milk' (adj. ''amolg-os''), by claiming that they milked female dogs. This name is commonly used in laboratory settings.
In Thailand, the species is called "ลิงแสม" (''Ling s̄æm''; literally 'mangrove monkeys') because it lives and forages in
mangrove forest
Mangrove forests, also called mangrove swamps, mangrove thickets or mangals, are productive wetlands that occur in coastal intertidal zones. Mangrove forests grow mainly at tropical and subtropical latitudes because mangroves cannot withstand fr ...
s.
Taxonomy
The 10
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of ''M. fascicularis'' are:
*
Common long-tailed macaque
Common may refer to:
Places
* Common, a townland in County Tyrone, Northern Ireland
* Boston Common, a central public park in Boston, Massachusetts
* Cambridge Common, common land area in Cambridge, Massachusetts
* Clapham Common, originally com ...
, ''M. f. fascicularis''
*
Burmese long-tailed macaque
Burmese may refer to:
* Something of, from, or related to Myanmar, a country in Southeast Asia
* Burmese people
* Burmese language
* Burmese alphabet
* Burmese cuisine
* Burmese culture
Animals
* Burmese cat
* Burmese chicken
* Burmese (hor ...
, ''M. f. aurea''
*
Nicobar long-tailed macaque
The Nicobar long-tailed macaque (''Macaca fascicularis umbrosa'', popularly known as the Nicobar monkey) is a subspecies of the crab-eating macaque (''M. fascicularis''), endemic to the Nicobar Islands in the Bay of Bengal. This primate is fou ...
, ''M. f. umbrosa''
*
Dark-crowned long-tailed macaque, ''M. f. atriceps''
*
Con Song long-tailed macaque, ''M. f. condorensis''
*
Simeulue long-tailed macaque, ''M. f. fusca''
*
Lasia long-tailed macaque
''Lasia'' is a genus of flowering plants in the family Araceae, native to Asia and New Guinea. The genus contains only two known species, '' Lasia spinosa'' and '' Lasia concinna''. ''Lasia'' was believed to be a monotypic genus until 1997 when ...
, ''M. f. lasiae''
*
Maratua long-tailed macaque, ''M. f. tua''
*
Kemujan long-tailed macaque, ''M. f. karimondjawae''
*
Philippine long-tailed macaque
The Philippine long-tailed macaque (''Macaca fascicularis philippensis'') is a subspecies of the crab-eating macaque, known in various Philippine languages as ''matching''/''matsing'' or the more general term ''unggoy'' ("monkey"). It is endemic ...
, ''M. f. philippensis''
Physical characteristics
![Ngarai_Sianok_sumatran_monkey](https://upload.wikimedia.org/wikipedia/commons/5/53/Ngarai_Sianok_sumatran_monkey.jpg)
The body length of the adult, which varies among subspecies, is with relatively short arms and legs. Males are considerably larger than females, weighing compared to the of females.
The tail is longer than the body, typically , which is used for balance when they jump distances up to .
The upper parts of the body are dark brown with light golden brown tips. The under parts are light grey with a dark grey/brown tail. Crab-eating macaques have backwards-directed crown hairs which sometimes form short crests on the midline. Their skin is black on their feet and ears, whereas the skin on the muzzle is a light grayish pink color. The eyelids often have prominent white markings and sometimes there are white spots on the ears. Males have a characteristic mustache and cheek
whisker
Vibrissae (; singular: vibrissa; ), more generally called Whiskers, are a type of stiff, functional hair used by mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarser ...
s, while females have only cheek whiskers. Crab-eating macaques have a cheek pouch which they use to store food while foraging. Females show no
perineal swelling.
Behavior
Group living
![Macaca fascicularis Ao Nang 5](https://upload.wikimedia.org/wikipedia/commons/9/94/Macaca_fascicularis_Ao_Nang_5.jpg)
Macaques live in
social group
In the social sciences, a social group can be defined as two or more people who interact with one another, share similar characteristics, and collectively have a sense of unity. Regardless, social groups come in a myriad of sizes and varieties ...
s that contain three to 20 females, their offspring, and one or many males. The groups usually have fewer males than females. In social groups of macaques, a clear
dominance hierarchy
In biology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social animal , social groups interact, creating a ranking system. A dominant higher-ranking i ...
is seen among females. These ranks remain stable throughout the female's lifetime and also can be sustained through generations of
matrilines. Females have their highest birth rates around 10 years of age and completely stop bearing young by age 24.
The social groups of macaques are female-bonded, meaning the males will disperse at the time of
puberty
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a boy. ...
. Thus, group
relatedness
The coefficient of relationship is a measure of the degree of consanguinity (or biological relationship) between two individuals. The term coefficient of relationship was defined by Sewall Wright in 1922, and was derived from his definition of th ...
on average appears to be lower than compared to
matrilines. More difference in relatedness occurs when comparing high-ranking lineages to lower ranking lineages, with higher-ranking individuals being more closely related to one another. Additionally, groups of dispersing males born into the same social groups display a range of relatedness, at times appearing to be brothers, while at other times appearing to be unrelated.
In addition to the matrilineal dominance hierarchy, male dominance rankings also exist.
Alpha males
In biology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social groups interact, creating a ranking system. A dominant higher-ranking individual is so ...
have a higher frequency of mating compared to their lower-ranking conspecifics. The increased success is due partially to his increased access to females and also due to female preference of an alpha male during periods of maximum
fertility
Fertility is the capability to produce offspring through reproduction following the onset of sexual maturity. The fertility rate is the average number of children born by a female during her lifetime and is quantified demographically. Fertili ...
. Though females have a preference for alpha males, they do display
promiscuous
Promiscuity is the practice of engaging in sexual activity frequently with different Sexual partner, partners or being indiscriminate in the choice of sexual partners. The term can carry a moral judgment. A common example of behavior viewed as pro ...
behavior. Through this behavior, females risk helping to rear a nonalpha offspring, yet benefit in two specific ways, both in regard to
aggressive
Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...
behavior. First, a decreased value is placed on one single
copulation
Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetra ...
. Moreover, the risk of
infanticide
Infanticide (or infant homicide) is the intentional killing of infants or offspring. Infanticide was a widespread practice throughout human history that was mainly used to dispose of unwanted children, its main purpose is the prevention of reso ...
is decreased due to the uncertainty of paternity.
Increasing group size leads to increased competition and energy spent trying to
forage
Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...
for resources, and in particular, food. Further, social tensions build and the prevalence of tension-reducing interactions like
social grooming
Social grooming is a behavior in which social animals, including humans, clean or maintain one another's body or appearance. A related term, allogrooming, indicates social grooming between members of the same species. Grooming is a major soci ...
fall with larger groups. Thus, group living appears to be maintained solely due to the safety against
predation
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...
.
Crab-eating macaques sometimes form mixed species groups with other primate species, including the
southern pig-tailed macaque
The southern pig-tailed macaque (''Macaca nemestrina''), also known as the Sundaland pig-tailed macaque and Sunda pig-tailed macaque, is a medium-sized macaque that lives in southern Thailand, Malaysia, and Indonesia. It is known locally as ber ...
,
dusky langur and
white-thighed surili.
They have been observed engaging in grooming with other primate species, including the southern pig-tailed macaque and
leaf monkey
The Colobinae or leaf-eating monkeys are a subfamily of the Old World monkey family that includes 61 species in 11 genera, including the black-and-white colobus, the large-nosed proboscis monkey, and the gray langurs. Some classifications split ...
s such as
Raffles' banded langur and the dusty langur.
[
]
Conflict
Group living in all species is dependent on the tolerance of other group members. In crab-eating macaques, successful social group living requires postconflict resolution. Usually, less dominant individuals lose to a higher-ranking individual when conflict arises. After the conflict has taken place, lower-ranking individuals tend to fear the winner of the conflict to a greater degree. In one study, this was seen in the ability to drink water together. Postconflict observations showed a staggered time between when the dominant individual begins to drink and the subordinate. Long-term studies reveal the gap in drinking time closes as the conflict moves further into the past.
Grooming and support in conflict among primate
Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians (monkeys and apes, the latter including huma ...
s is considered to be an act of reciprocal altruism
In evolutionary biology, reciprocal altruism is a behaviour whereby an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, with the expectation that the other organism will act in a similar m ...
. In crab-eating macaques, an experiment was performed in which individuals were given the opportunity to groom one another under three conditions: after being groomed by the other, after grooming the other, and without prior grooming. After grooming took place, the individual that received the grooming was much more likely to support their groomer than one that had not previously groomed that individual. These results support the reciprocal altruism theory of grooming in long-tailed macaques.
Crab-eating macaques demonstrate two of the three forms of suggested postconflict behavior. In both captive and wild studies, the monkeys demonstrated reconciliation, or an affiliative interaction between former opponents, and redirection, or acting aggressively towards a third individual. Consolation was not seen in any study performed.
Postconflict anxiety
Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...
has been reported in crab-eating macaques that have acted as the aggressor. After a conflict within a group, the aggressor appears to scratch itself at a higher rate than before the conflict. Though the scratching behavior cannot definitely be termed as an anxious behavior, evidence suggests this is the case. An aggressor's scratching decreases significantly after reconciliation. This suggests reconciliation rather than a property of the conflict is the cause of the reduction in scratching behavior. Though these results seem counterintuitive, the anxiety of the aggressor appears to have a basis in the risks of ruining cooperative
A cooperative (also known as co-operative, co-op, or coop) is "an autonomous association of persons united voluntarily to meet their common economic, social and cultural needs and aspirations through a jointly owned and democratically-control ...
relationships with the opponent.
Kin altruism and spite
In a study, a group of crab-eating macaques was given ownership of a food object. Unsurprisingly, adult females favored their own offspring by passively, yet preferentially, allowing them to feed on the objects they held. When juveniles were in possession of an object, mothers robbed them and acted aggressively at an increased rate towards their own offspring compared to other juveniles. These observations suggest close proximity influences behavior in ownership, as a mother's kin are closer to her on average. When given a nonfood object and two owners, one being a kin and one not, the rival will choose the older individual to attack regardless of kinship
In anthropology, kinship is the web of social relationships that form an important part of the lives of all humans in all societies, although its exact meanings even within this discipline are often debated. Anthropologist Robin Fox says that ...
. Though the hypothesis remains that mother-juvenile relationships may facilitate social learning of ownership, the combined results clearly point to aggression towards the least-threatening individual.
A study was conducted in which food was given to 11 females. They were then given a choice to share the food with kin or nonkin. The kin altruism hypothesis suggests the mothers would preferentially give food to their own offspring. Yet eight of the 11 females did not discriminate between kin and nonkin. The remaining three did, in fact, give more food to their kin. The results suggest it was not kin selection
Kin selection is the evolutionary strategy that favours the reproductive success of an organism's relatives, even when at a cost to the organism's own survival and reproduction. Kin altruism can look like altruistic behaviour whose evolution i ...
, but instead spite that fueled feeding kin preferentially. This is due to the observation that food was given to kin for a significantly longer period of time than needed. The benefit to the mother is decreased due to less food availability for herself and the cost remains great for nonkin due to not receiving food. If these results are correct, crab-eating macaques are unique in the animal kingdom, as they appear not only to behave according to the kin selection theory, but also act spitefully toward one another.
Reproduction
After a gestation
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregna ...
period of 162–193 days, the female gives birth to one infant. The infant's weight at birth is about . Infants are born with black fur which will begin to turn to a grey or reddish-brown shade (depending on the subspecies) after about three months of age. This natal
NATAL or Natal may refer to:
Places
* Natal, Rio Grande do Norte, a city in Brazil
* Natal, South Africa (disambiguation), a region in South Africa
** Natalia Republic, a former country (1839–1843)
** Colony of Natal, a former British colony ( ...
coat may indicate to others the status of the infant, and other group members treat infants with care and rush to their defense when distressed. Immigrant males sometimes kill infants not their own in order to shorten interbirth intervals. High-ranking females will sometimes kidnap
In criminal law, kidnapping is the unlawful confinement of a person against their will, often including transportation/asportation. The asportation and abduction element is typically but not necessarily conducted by means of force or fear: the p ...
the infants of lower-ranking females. These kidnappings can result in the death of the infants, as the other female is usually not lactating. A young juvenile stays mainly with its mother and relatives. As male juveniles get older, they become more peripheral to the group. Here they play together, forming crucial bonds that may help them when they leave their natal group. Males that emigrate
Emigration is the act of leaving a resident country or place of residence with the intent to settle elsewhere (to permanently leave a country). Conversely, immigration describes the movement of people into one country from another (to permanentl ...
with a partner are more successful than those that leave alone. Young females, though, stay with the group and become incorporated into the matriline into which they were born.
Male crab-eating macaques groom females to increase the chance of mating. A female is more likely to engage in sexual activity with a male that has recently groomed her than with one that has not.
Diet
Despite its name, the crab-eating macaque typically does not consume crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...
s; rather, it is an opportunistic omnivore
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutr ...
, eating a variety of animals and plants. Although fruits and seeds make up 60 - 90% of its diet, it also eat leaves, flowers, roots, and bark. It sometimes preys on vertebrates including bird chicks, nesting female birds, lizards, frogs, and fish, invertebrates, and bird eggs. In Indonesia, it has become a proficient swimmer and diver for crabs and other crustaceans in mangrove swamps. In Bukit Timah
Bukit Timah, often abbreviated as Bt Timah, is a planning area and residential estate located in the westernmost part of the Central Region of Singapore. Bukit Timah lies roughly from the Central Business District, bordering the Central Wat ...
, Singapore
Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, borde ...
its diet consists of 44% fruit, 27% animal matter, 15% flowers and other plant matter, and 14% food provided by humans.
The crab-eating macaque exhibits particularly low tolerance for swallowing seeds. Despite its inability to digest seeds, many primates of similar size swallow large seeds, up to , and simply defecate them whole. The crab-eating macaque, though, spits seeds out if they are larger than . This decision to spit seeds is thought to be adaptive; it avoids filling the monkey's stomach with wasteful bulky seeds that cannot be used for energy. It also can help the plants by distributing seeds to new areas: Crab-eating macaques eat durian
The durian (, ) is the edible fruit of several tree species belonging to the genus ''Durio''. There are 30 recognised ''Durio'' species, at least nine of which produce edible fruit. ''Durio zibethinus'', native to Borneo and Sumatra, is the onl ...
s such as ''Durio graveolens
''Durio graveolens,'' sometimes called the red-fleshed durian, orange-fleshed durian, or yellow durian, is a species of tree in the family Malvaceae. It is one of six species of durian named by Italian naturalist Odoardo Beccari. The specific ...
'' and '' D. zibethinus'', and are a major seed disperser
In Spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant.
Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, ...
for the latter species.
Although the crab-eating macaque is ecologically well-adapted and poses no threat to population stability of prey species in its native range, in areas where it is not native, it can pose a substantial threat to biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') l ...
. Some believe the crab-eating macaque is responsible for the extinction of forest birds by threatening critical breeding areas as well as eating the eggs and chicks of endangered forest birds.
The crab-eating macaque can become a synanthrope
A synanthrope (from the Greek σύν ''syn'', "together with" + ἄνθρωπος ''anthropos'', "man") is a member of a species of wild animal or plant that lives near, and benefits from, an association with human beings and the somewhat artific ...
, living off human resources. It feeds in cultivated fields on young dry rice, cassava leaves, rubber fruit, taro plants, coconuts, mangos, and other crops, often causing significant losses to local farmers. In villages, towns, and cities, it frequently takes food from garbage cans and refuse piles. It can become unafraid of humans in these conditions, which can lead to macaques directly taking food from people, both passively and aggressively.
Tool use
In Thailand and Myanmar, crab-eating macaques use stone tools to open nuts, oysters and other bivalves, and various types of sea snail
Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...
s ( nerites, muricid
Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With about 1,600 living species, the Muricidae represent almost 10% of the Neoga ...
s, trochids, etc.) along the Andaman sea coast and offshore islands.
Another instance of tool use is washing and rubbing foods such as sweet potatoes, cassava
''Manihot esculenta'', common name, commonly called cassava (), manioc, or yuca (among numerous regional names), is a woody shrub of the spurge family, Euphorbiaceae, native to South America. Although a perennial plant, cassava is extensively ...
roots, and papaya
The papaya (, ), papaw, () or pawpaw () is the plant species ''Carica papaya'', one of the 21 accepted species in the genus ''Carica'' of the family Caricaceae. It was first domesticated in Mesoamerica, within modern-day southern Mexico and ...
leaves before consumption. Crab-eating macaques either soak these foods in water or rub them through their hands as if to clean them. They also peel the sweet potatoes, using their incisor
Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, whe ...
s and canine teeth. Adolescents appear to acquire these behaviors by observational learning
Observational learning is learning that occurs through observing the behavior of others. It is a form of social learning which takes various forms, based on various processes. In humans, this form of learning seems to not need reinforcement to oc ...
of older individuals.
Distribution and habitat
The crab-eating macaque lives in a wide variety of habitats, including primary lowland rainforest
Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...
s, disturbed and secondary rainforests, shrubland, and riverine and coastal forests of nipa palm
''Nypa fruticans'', commonly known as the nipa palm (or simply nipa, from ms, nipah) or mangrove palm, is a species of palm native to the coastlines and estuarine habitats of the Indian and Pacific Oceans. It is the only palm considered adapte ...
and mangrove
A mangrove is a shrub or tree that grows in coastal saline water, saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evoluti ...
. They also easily adjust to human settlements; they are considered sacred at some Hindu temples and on some small islands, but are pests around farms and villages. Typically, they prefer disturbed habitats and forest periphery. The native range of this species includes most of mainland Southeast Asia
Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...
, from extreme southeastern Bangladesh
Bangladesh (}, ), officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 165 million people in an area of . Bangladesh is among the mos ...
south through the Malay Peninsula
The Malay Peninsula (Malay: ''Semenanjung Tanah Melayu'') is a peninsula in Mainland Southeast Asia. The landmass runs approximately north–south, and at its terminus, it is the southernmost point of the Asian continental mainland. The area ...
and Singapore
Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, borde ...
, the Maritime Southeast Asia
Maritime Southeast Asia comprises the countries of Brunei, Indonesia, Malaysia, the Philippines, Singapore, and East Timor. Maritime Southeast Asia is sometimes also referred to as Island Southeast Asia, Insular Southeast Asia or Oceanic Sout ...
islands of Sumatra
Sumatra is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...
, Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...
, and Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
, offshore islands, the islands of the Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
, and the Nicobar Islands
The Nicobar Islands are an archipelagic island chain in the eastern Indian Ocean. They are located in Southeast Asia, northwest of Aceh on Sumatra, and separated from Thailand to the east by the Andaman Sea. Located southeast of the Indian s ...
in the Bay of Bengal
The Bay of Bengal is the northeastern part of the Indian Ocean, bounded on the west and northwest by India, on the north by Bangladesh, and on the east by Myanmar and the Andaman and Nicobar Islands of India. Its southern limit is a line between ...
. This primate is a rare example of a terrestrial mammal that violates the Wallace line
The Wallace Line or Wallace's Line is a faunal boundary line drawn in 1859 by the British naturalist Alfred Russel Wallace and named by English biologist Thomas Henry Huxley that separates the biogeographical realms of Asia and Wallacea, a tran ...
.
Introduced range
The crab-eating macaque is an introduced alien species in several countries, including Hong Kong
Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delt ...
, Taiwan
Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...
, West Papua, Papua New Guinea
Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...
, New Britain
New Britain ( tpi, Niu Briten) is the largest island in the Bismarck Archipelago, part of the Islands Region of Papua New Guinea. It is separated from New Guinea by a northwest corner of the Solomon Sea (or with an island hop of Umboi the Dam ...
, New Ireland, New Caledonia
)
, anthem = ""
, image_map = New Caledonia on the globe (small islands magnified) (Polynesia centered).svg
, map_alt = Location of New Caledonia
, map_caption = Location of New Caledonia
, mapsize = 290px
, subdivision_type = Sovereign st ...
, Solomon Islands
Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...
, Fiji
Fiji ( , ,; fj, Viti, ; Fiji Hindi: फ़िजी, ''Fijī''), officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists ...
, Tonga
Tonga (, ; ), officially the Kingdom of Tonga ( to, Puleʻanga Fakatuʻi ʻo Tonga), is a Polynesian country and archipelago. The country has 171 islands – of which 45 are inhabited. Its total surface area is about , scattered over in ...
, Samoa
Samoa, officially the Independent State of Samoa; sm, Sāmoa, and until 1997 known as Western Samoa, is a Polynesian island country consisting of two main islands (Savai'i and Upolu); two smaller, inhabited islands (Manono Island, Manono an ...
, Nauru
Nauru ( or ; na, Naoero), officially the Republic of Nauru ( na, Repubrikin Naoero) and formerly known as Pleasant Island, is an island country and microstate in Oceania, in the Central Pacific. Its nearest neighbour is Banaba Island in Ki ...
, Vanuatu
Vanuatu ( or ; ), officially the Republic of Vanuatu (french: link=no, République de Vanuatu; bi, Ripablik blong Vanuatu), is an island country located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is east of no ...
, Pohnpei
Pohnpei "upon (''pohn'') a stone altar (''pei'')" (formerly known as Ponape or Ascension, Proto-Chuukic-Pohnpeic: ''*Fawo ni pei)'' is an island of the Senyavin Islands which are part of the larger Caroline Islands group. It belongs to Pohnpei ...
, Anggaur Island in Palau
Palau,, officially the Republic of Palau and historically ''Belau'', ''Palaos'' or ''Pelew'', is an island country and microstate in the western Pacific. The nation has approximately 340 islands and connects the western chain of the Caro ...
, and Mauritius
Mauritius ( ; french: Maurice, link=no ; mfe, label=Mauritian Creole, Moris ), officially the Republic of Mauritius, is an island nation in the Indian Ocean about off the southeast coast of the African continent, east of Madagascar. It incl ...
. This has led the Invasive Species Specialist Group of the International Union for Conservation of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
to list the crab-eating macaque as one of the "100 of the World's Worst Invasive Alien Species
100 of the World's Worst Invasive Alien Species is a list of invasive species compiled in 2014 by the Global Invasive Species Database, a database of invasive species around the world. The database is run by the Invasive Species Specialist Group ...
". In Mauritius, it is a threat for the endemic and endangered ''Roussea simplex
''Roussea simplex'' is a woody climber of 4–6 m high, that is endemic to the mountain forest of Mauritius. It is the only species of the genus ''Roussea'', which is assigned to the family Rousseaceae. It has opposing, entire, obovate, gre ...
'', as it destroys its flowers. It also hinders germination of some endemic trees by destroying most of their fruits when unripe and competes with the endemic endangered Mauritian flying fox
The Mauritian flying fox (''Pteropus niger''), also known as Greater Mascarene flying fox or Mauritius fruit bat is a large megabat species endemic to Mauritius and La Réunion.
Description
The Mauritian flying fox can reach a wingspan of 80&nb ...
for native fruits.
Where it is not a native species, particularly on island ecosystems whose species often evolved in isolation from large predators, it is a documented threat to many native species. The immunovaccine porcine zona pellucida Porcine zona pellucida (PZP) is the zona pellucida extracted from the ovaries of pigs which is used as a source of antigens for immunocontraception.
The zona pellucida is a thick membrane that surrounds the unfertilised eggs of mammals. In order fo ...
(PZP), which causes infertility in females, is currently being tested in Hong Kong to investigate its use as potential population control.
Relationship with humans
Crab-eating macaques extensively overlap with humans across their range in Southeast Asia. Consequently, they live together in many locations. Some of these areas are associated with religious sites and local customs, such as the temples of Bali
Bali () is a province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller neighbouring islands, notably Nusa Penida, Nusa Lembongan, and Nu ...
in Indonesia, Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...
, and Cambodia
Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailand t ...
, while other areas are characterized by conflict as a result of habitat loss and competition over food and space. Humans and crab-eating macaques have shared environments since prehistoric times, and both tend to frequent forest and river edge habitats. Crab-eating macaques are occasionally used as a food source for some indigenous forest-dwelling peoples. In Mauritius, they are captured and sold to the pharmaceutical industry, and in Angaur and Palau, they are sold as pets. Macaques feed on sugarcane
Sugarcane or sugar cane is a species of (often hybrid) tall, Perennial plant, perennial grass (in the genus ''Saccharum'', tribe Andropogoneae) that is used for sugar Sugar industry, production. The plants are 2–6 m (6–20 ft) tall with ...
and other crops, affecting agriculture and livelihoods, and can be aggressive towards humans. Macaques may carry potentially fatal human diseases, including herpes B virus
B-virus (''Macacine alphaherpesvirus 1''; McHV-1; formerly ''Macacine herpesvirus 1'', ''Cercopithecine herpesvirus 1'', CHV-1), ''Herpesvirus simiae'', or ''Herpes virus B'' is the ''Simplexvirus'' infecting macaque monkeys. B virus is very sim ...
. In Singapore
Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, borde ...
, they have adapted into the urban environment.
The macaques have also developed a reputation for actively stealing items from humans (cameras, eyeglasses, hats, etc.), then refusing to return their stolen goods until given food in return. This unique form of kleptoparasitism
Kleptoparasitism (etymologically, parasitism by theft) is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, which can mean when foo ...
(known as "robbing and bartering") has primarily been observed in smaller groups of macaques living near Hindu temples and tourist-heavy areas, suggesting it is a learned behaviour within social groups, in response to realizing that humans would trade food for their possessions back.
In scientific research
''M. fascicularis'' is also used extensively in medical experiments, in particular those connected with neuroscience
Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions and disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, development ...
and disease. Due to their close physiology, they can share infections with humans. Some cases of concern have been an isolated event of '' Reston ebolavirus'' found in a captive-bred population shipped to the US from the Philippines, which was later found to be a strain of Ebola that has no known pathological consequences in humans, unlike the African strains. Furthermore, they are a known carrier of monkey B virus (''Herpesvirus simiae''), a virus which has produced disease in some lab workers working mainly with rhesus macaques (''M. mulatta''). Nafovanny, the largest facility for the captive breeding of nonhuman primates in the world, houses 30,000 macaques . ''Plasmodium knowlesi
''Plasmodium knowlesi'' is a parasite that causes malaria in humans and other primates. It is found throughout Southeast Asia, and is the most common cause of human malaria in Malaysia. Like other ''Plasmodium'' species, ''P. knowlesi'' has a li ...
'', which causes malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. S ...
in ''M. fascicularis'', can also infect humans. A few cases have been documented in humans, but for how long humans have been getting infections of this malarial strain is unknown. It is, therefore, not possible to assess if this is a newly emerging health threat, or if just newly discovered due to improved malarial detection techniques. Given the long history of humans and macaques living together in Southeast Asia, it is likely the latter.
The use of crab-eating macaques and other nonhuman primates in experimentation is controversial with critics charging that the experiments are cruel, unnecessary and lead to dubious findings. One of the most well known examples of experiments on crab-eating macaques is the 1981 Silver Spring monkeys case.
In 2014, 21,768 crab-eating macaques were imported in the United States to be used in experimentation.
Conservation status
The crab-eating macaque has the third-largest range of any primate species, behind only humans and rhesus macaque
The rhesus macaque (''Macaca mulatta''), colloquially rhesus monkey, is a species of Old World monkey. There are between six and nine recognised subspecies that are split between two groups, the Chinese-derived and the Indian-derived. Generally b ...
s. The IUCN
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
Red List categorizes the species as endangered, and CITES
CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of interna ...
lists them as Appendix II ("not necessarily threatened with extinction", in which trade must be controlled to avoid use incompatible with their survival). Its IUCN status was changed from Least Concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
in 2020 as a result of declining population resulting from hunting and troublesome interactions with humans, despite its wide range and ability to adapt to different habitats. A 2008 review of their populations suggests a need for better monitoring of populations due to increased wild trade and rising levels of human-macaque conflict, which are reducing overall population levels despite the species being widely distributed.
Each subspecies faces differing levels of threats, and too little information is available on some subspecies to assess their conditions. The ''M. f. umbrosa'' subspecies is likely of important biological significance and has been recommended as a candidate for protection in the Nicobar Islands
The Nicobar Islands are an archipelagic island chain in the eastern Indian Ocean. They are located in Southeast Asia, northwest of Aceh on Sumatra, and separated from Thailand to the east by the Andaman Sea. Located southeast of the Indian s ...
, where its small, native population has been seriously fragmented, and is listed as vulnerable on the IUCN Red List. The Philippine long-tailed macaque (''M. f. philippensis'') is listed as near threatened, and ''M. f. condorensis'' is vulnerable. All other subspecies are listed as data deficient and need further study; although recent work is showing ''M. f. aurea'' and ''M. f. karimondjawae'' need increased protection. One concern for conservation is, in areas where ''M. fascicularis'' is not native, their populations need to be monitored and managed to reduce their impact on native flora and fauna.
Genome
The genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...
of the crab-eating macaque has been sequenced.
Clones
On 24 January 2018, scientists in China reported in the journal ''Cell
Cell most often refers to:
* Cell (biology), the functional basic unit of life
Cell may also refer to:
Locations
* Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery ...
'' the creation of two crab-eating macaque clones
Clone or Clones or Cloning or Cloned or The Clone may refer to:
Places
* Clones, County Fermanagh
* Clones, County Monaghan, a town in Ireland
Biology
* Clone (B-cell), a lymphocyte clone, the massive presence of which may indicate a pathologi ...
, named ''Zhong Zhong and Hua Hua
Zhong Zhong (, born 27 November 2017) and Hua Hua (, born 5 December 2017) are a pair of identical crab-eating macaques (also referred to as cynomolgus monkeys) that were created through somatic cell nuclear transfer (SCNT), the same cloning te ...
'', using the complex DNA transfer method that produced ''Dolly'' the sheep. This makes Zhong Zhong and Hua Hua the first primates to be cloned using the somatic cell nuclear transfer
In genetics and developmental biology, somatic cell nuclear transfer (SCNT) is a laboratory strategy for creating a viable embryo from a body cell and an egg cell. The technique consists of taking an enucleated oocyte (egg cell) and implanting a ...
method.
See also
* Maggie the Macaque Maggie the Monkey, also Maggie the Macaque (born 1991), is a crab-eating macaque from the Bowmanville Zoo used as an animal oracle to make predictions of the Stanley Cup Playoffs.
History
Maggie was born and hand-raised at the Bowmanville Zoo ...
* Prostitution among animals
Prostitution among animals is the phenomena where different species of non-human animals practice the exchange of sex for different benefits. A few studies suggest that prostitution exists among different species of animals such as Adélie pengu ...
References
External links
Bonadio, C. 2000. "Macaca fascicularis" (On-line), Animal Diversity Web. Accessed March 10, 2006.
Primate Info Net ''Macaca fascicularis'' Factsheet
ISSG Database: Ecology of ''Macaca fascicularis''
Primate Info Net: ''Macaca fascicularis''
BBC Factfile on M. fascicularis
video produced by the British Union for the Abolition of Vivisection
Cruelty Free International is an animal protection and advocacy group that campaigns for the abolition of all animal experiments. They organise certification of cruelty-free products which are marked with the symbol of a leaping bunny.
It wa ...
following an undercover investigation at a captive-breeding facility for long-tailed macaques in Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
.
*
{{Authority control
crab-eating macaque
The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaqu ...
Primates of Southeast Asia
Mammals of Oceania
Crab-eating macaque
The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaqu ...
Mammals of Bangladesh
Mammals of Borneo
Mammals of Brunei
Mammals of Myanmar
Mammals of Cambodia
Mammals of Timor
Mammals of Indonesia
Mammals of Laos
Mammals of Malaysia
Mammals of the Philippines
Mammals of Singapore
Mammals of Thailand
Mammals of Vietnam
Mammals of Fiji
Mammals of Samoa
Mammals of Tonga
Crab-eating macaque
The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaqu ...
Crab-eating macaque
The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaqu ...
Crab-eating macaque
The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaqu ...
Articles containing video clips