Capuchin monkey
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[Photo] Weeper Capuchin, Cebus olivaceus, is a capuchin monkey from South America. It is found in Brazil, Guyana, French Guiana, Suriname and Venezuela. Weeper Capuchin (hebrew:????????'???? ?????????? (????????'???? ??????????)) taken in the Zoological Center of Tel Aviv-Ramat Gan, Israel. Date 17.7.2007. Author Pacman (http://commons.wikimedia.org/wiki/User:Pacman). License: public domain

The capuchins are the group of New World monkeys classified as genus Cebus. Their name comes from their coloration, which resembles the cowls worn by the Franciscan Capuchin order of Catholic friars. Cebus is the only genus in subfamily Cebinae.

The range of the capuchin monkeys includes Central America (Honduras) and middle South America (middle Brazil, eastern Peru, Paraguay).

Capuchins generally resemble the friars of their namesake. Their body, arms, legs and tail are all darkly (black or brown) colored, while the face, throat and chest are white colored, and their head has a black cap. They reach a length of 30 to 56 cm (12 - 22 inches), with tails that are just as long as the body. They weigh up to 1.3 kg (2 lb, 13 oz), with brains of mass 35-40g. They are considered the most intelligent New World monkeys.

Like most New World monkeys, capuchins are diurnal and arboreal. With the exception of a midday nap, they spend their entire day searching for food. At night they sleep in the trees, wedged between branches. They are undemanding regarding their habitat and can thus be found in many differing areas. Among the natural enemies of the capuchins are large falcons, cats and snakes.

The diet of the capuchins is more varied than other monkeys in the family Cebidae. They are omnivores, eating not only fruits, nuts, seeds and buds, but also insects, spiders, bird eggs and small vertebrates. Capuchins living near water will also eat crabs and shellfish by cracking their shells with stones.

Easily recognized as the "organ grinder" monkeys, capuchins are sometimes kept as exotic pets. They are also sometimes used as service animals. Sometimes they plunder fields and crops and are seen as troublesome by nearby human populations. In some regions they have become rare due to the destruction of their habitat.

Social structure
Capuchins live together in groups of 6 to 40 members. These groups consist of related females and their offspring, as well as several males. Usually groups are dominated by a single male, who has primary rights to mate with the females of the group. Mutual grooming as well as vocalization serves as communication and stabilization of the group dynamics. These primates are territorial animals, distinctly marking a central area of their territory with urine and defending it against intruders, though outer zones of these areas may overlap.

Females bear young every two years following a 160 to 180 day gestation. The young cling to their mother's chest until they are larger, when they move to her back. Adult male capuchins rarely take part in caring for the young. Within four years for females and eight years for males, juveniles become fully mature. In captivity, individuals have reached an age of 45 years, although life expectancy in nature is only 15 to 25 years.

Intelligence
Capuchins are considered the most intelligent New World monkeys and are often used in laboratories. The Tufted Capuchin is especially noted for its long-term tool usage, one of the few examples of primate tool use other than by apes. Upon seeing macaws eating palm nuts, cracking them open with their beaks, these capuchins will select a few of the ripest fruits, nip off the tip of the fruit and drink down the juice, then seemingly discard the rest of the fruit with the nut inside. When these discarded fruits have hardened and become slightly brittle, the capuchins will gather them up again and take them to a large flat boulder where they have previously gathered a few river stones from up to a mile away. They will then use these stones, some of them weighing as much as the monkeys, to crack open the fruit to get to the nut inside. Young capuchins will watch this process to learn from the older, more experienced adults.

During the mosquito season, they crush up millipedes and rub the remains on their backs. This acts as a natural insect repellent.

Self-awareness
When presented with a reflection, capuchin monkeys react in a way that indicates an intermediate state between seeing the mirror as another individual and recognizing the image as self.

Most animals react to seeing their reflection as if encountering another individual they don't recognize. An experiment with capuchins shows that they react to a reflection as a strange phenomenon, but not as if seeing a strange capuchin.

In the experiment, capuchins were presented with three different scenarios:

Seeing an unfamiliar, same-sex monkey on the other side of a clear barrier
Seeing a familiar, same-sex monkey on the other side of a clear barrier
A mirror showing a reflection of the monkey

With scenario 1, females appeared anxious and avoided eye-contact. Males made threatening gestures. In scenario 2, there was little reaction by either males or females.

When presented with a reflection, females gazed into their own eyes and made friendly gestures such as lip-smacking and swaying. Males made more eye contact than with strangers or familiar monkeys but reacted with signs of confusion or distress, such as squealing, curling up on the floor or trying to escape from the test room.

Theory of mind
The question of whether capuchin monkeys have a theory of mind -- whether they can understand what another creature may know or think -- has been neither proven nor disproven conclusively. If confronted with a knower-guesser scenario, where one trainer can be observed to know the location of food and another trainer merely guesses the location of food, capuchin monkeys can learn to rely on the knower. This has, however, been refuted as conclusive evidence for a theory of mind as the monkeys may have learned to discriminate knower and guesser by other means. Non-human great apes have not been proven to develop a theory of mind either; human children commonly develop a theory of mind around the ages 3 and 4.

Human assistance
Some organizations, such as Helping Hands in Boston, Massachusetts, have been training capuchin monkeys to assist quadriplegics in a manner similar to mobility assistance dogs. After being socialized in a human home as infants, the monkeys undergo extensive training before being placed with a quadriplegic. Around the house, the monkeys help out by doing tasks including microwaving food, washing the quadriplegic's face, and opening drink bottles.

Classification
Genus Cebus
C. capucinus group
White-headed Capuchin, Cebus capucinus
White-fronted Capuchin, Cebus albifrons
Cebus albifrons albifrons
Cebus albifrons unicolor
Shock-headed Capuchin, Cebus albifrons cuscinus
Trinidad White-fronted Capuchin, Cebus albifrons trinitatis
Ecuadorian Capuchin, Cebus albifrons aequatorialis
Varied Capuchin, Cebus albifrons versicolor
Weeper Capuchin, Cebus olivaceus
Kaapori Capuchin, Cebus kaapori
C. apella group
Black-capped, Brown or Tufted Capuchin, Cebus apella
Guiana Brown Capuchin, Cebus apella apella
Cebus apella fatuellus
Margarita Island Capuchin, Cebus apella ?margaritae
Large-headed Capuchin, Cebus apella macrocephalus
Cebus apella peruanus
Cebus apella tocantinus
Black-striped Capuchin, Cebus libidinosus
Cebus libidinosus libidinosus
Cebus libidinosus pallidus
Cebus libidinosus paraguayanus
Cebus libidinosus juruanus
Black Capuchin, Cebus nigritus
Cebus nigritus nigritus
Crested Capuchin or Robust Tufted Capuchin, Cebus nigritus robustus
Cebus nigritus cucullatus
Golden-bellied Capuchin, Cebus xanthosternos
Blond Capuchin, Cebus queirozi*
*New species.

http://en.wikipedia.org/wiki/Capuchin_monkey

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