Capuchin monkey

White-headed Capuchin
White-headed Capuchin (Cebus capucinus)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Cebidae
Subfamily: Cebinae
Bonaparte, 1831
Genus: Cebus
Erxleben, 1777
Type species
Simia capuchin
Linnaeus, 1758
Species

Cebus capucinus
Cebus albifrons
Cebus olivaceus
Cebus kaapori
Cebus apella
Cebus flavius
Cebus libidinosus
Cebus nigritus
Cebus xanthosternos
Tufted Capuchin (Cebus apella)
Tufted Capuchin (Cebus apella)

The capuchins (pronounced /ˈkæpjʊtʃɪn/ or /ˈkæpjʊʃɪn/) are New World monkeys of the genus Cebus. The range of capuchin monkeys includes Central America and South America as far south as northern Argentina. Cebus is the only genus in subfamily Cebinae.

Contents

Etymology

The word capuchin derives from a group of friars named the Order of Friars Minor Capuchin, an offshoot from the Franciscans, who wear brown robes with large hoods covering their heads. When explorers reached the Americas in the 15th century they found small monkeys who resembled these monks and named them capuchins.[1] When the scientists described a specimen (thought to be a Golden-bellied Capuchin) they noted that: "his muzzle of a tanned color,... with the lighter color around his eyes that melts into the white at the front, his cheeks..., give him the looks that involuntarily reminds us of the appearance that historically in our country represents ignorance, laziness, and sensuality."[2] The scientific name of the genus, Cebus, on the other hand, comes from the Greek word kêbos,[3] meaning a long-tailed monkey.

Classification

The species-level taxonomy of this genus remains highly controversial, and alternative treatments than the one listed below have been suggested.[4][5][6][7]

* Rediscovered species.[9]

Physical characteristics

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 heads have a black cap. They reach a length of 30 to 56 cm (12–22 in), with tails that are just as long as the body. They weigh up to 2 and a half pounds after reaching their final weight at adulthood

Behaviour

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. Potential predators include jaguars, cougars, jaguarundis, coyotes, tayras, snakes, crocodiles, and raptors, although there has only been one published observation of a predator taking a capuchin in the wild.[1] The main predator of the Tufted Capuchin is the Harpy Eagle, which has been seen bringing several capuchins back to its nest.[1]

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, birds' eggs, and small vertebrates. Capuchins living near water will also eat crabs and shellfish by cracking their shells with stones.[10]

Social structure

Capuchins live together in groups of 10 to 35 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, though the White-headed Capuchin groups are led by both an alpha male and an alpha female. 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.

Life history

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[11] 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.[12] It may take a capuchin up to 8 years to master this skill.[13]

In 2005, experiments were conducted on the ability for capuchins to use money. After several months of training, the monkeys began showing traits considered to depict understanding of the concept of money that were previously believed to be restricted to humans (such as responding rationally to price shocks). Most striking was one possible case of prostitution.[14]

During the mosquito season, they crush up millipedes and rub the remains on their backs. This acts as a natural insect repellent.[15]

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:

  1. Seeing an unfamiliar, same-sex monkey on the other side of a clear barrier
  2. Seeing a familiar, same-sex monkey on the other side of a clear barrier
  3. 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.[16]

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.[17] 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.[18] 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.

Relationship with humans

Easily recognized as the "organ grinder" or "greyhound jockey" monkeys, capuchins are sometimes kept as exotic pets. Sometimes they plunder fields and crops and are seen as troublesome by nearby human populations.[1] In some regions they have become rare due to the destruction of their habitat.[1]

They are also used as service animals, sometimes being called "nature's butlers."[19] Some organizations have been training capuchin monkeys to assist quadriplegics as monkey helpers 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.[19]

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 Fragaszy et al. (2004). The complete capuchin : the biology of the genus Cebus. Cambridge University Press. p. 5. ISBN 9780521661164. OCLC 55875701. 
  2. ↑ Saint-Hilaire, E. G. & Cuvier, F. G. (1924). Histoire Naturelle des Mammifères. Paris, impr. de C. de Lasteyrie. OCLC 166026273. 
  3. ↑ William Rossiter (1879). An illustrated dictionary of scientific terms. London&Glasgow, William Collins, Sons, and Company. 
  4. ↑ Amaral, P. J. S, Finotelo, L. F. M., De Oliveira, E. H. C, Pissinatti, A., Nagamachi, C. Y., & Pieczarka, J. C. (2008).Phylogenetic studies of the genus Cebus (Cebidae-Primates) using chromosome painting and G-banding. BMC Evol Biol. 2008; 8: 169.
  5. ↑ Rylands, A. B., Kierulff, M. C. M., & Mittermeier, R. A. (2005). Notes on the taxonomy and distributions of the tufted capuchin monkeys (Cebus, Cebidae) of South America. Lundiana 6 (supp.): 97-110
  6. ↑ Silva Jr., J. de S. (2001). Especiação nos macacos-prego e caiararas, gênero Cebus Erxleben, 1777 (Primates, Cebidae). PhD thesis, Rio de Janeiro, Universidade Federal do Rio de Janeiro.
  7. ↑ IUCN 2008. 2008 IUCN Red List of Threatened Species. Accessed 23 November 2008
  8. ↑ Groves, C. (2005). Wilson, D. E., & Reeder, D. M, eds. ed. Mammal Species of the World (3rd ed.). Baltimore: Johns Hopkins University Press. pp. 136–138. ISBN 0-801-88221-4. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=12100255. 
  9. ↑ de Oliveira, M. M. & Langguth, A. (2006). "Rediscovery of Marcgrave’s capuchin monkey and designation of a neotype for Simia flavia Schreber, 1774 (Primates, Cebidae)" (PDF). Boletim do Museu Nacional: Nova Série: Zoologia (523): 1–16. http://acd.ufrj.br/~museuhp/CP/Bol-Zool/BolZool2006/Bol%20Zool%20MN%20523.pdf.  See also: Mendes Pontes, A. R., Malta, A. & Asfora, P. H. (2006). "A new species of capuchin monkey, genus Cebus Erxleben (Cebidae, Primates): found at the very brink of extinction in the Pernambuco Endemism Centre" (PDF). Zootaxa (1200): 1–12. http://www.mapress.com/zootaxa/2006f/zt01200p012.pdf. 
  10. ↑ Port-Carvalhoa, M., Ferraria, S. F. & Magalhãesc, C. (2004). "Predation of Crabs by Tufted Capuchins (Cebus apella) in Eastern Amazonia". Folia Primatol 75 (3): 154–156. doi:10.1159/000078305. PMID 15240980. 
  11. ↑ "Black-faced Capuchin". Amazonian Rainforest. Monkey Jungle. http://www.monkeyjungle.com/amazonian.htm. Retrieved 2008-10-13. 
  12. ↑ Boinski, S., Quatrone, R. P. & Swartz, H. (2008). "Substrate and Tool Use by Brown Capuchins in Suriname: Ecological Contexts and Cognitive Bases". American Anthropologist 102 (4): 741–761. doi:10.1525/aa.2000.102.4.741. 
  13. ↑ Life series. 2009. Episode 1. BBC.
  14. ↑ "Monkey Business". STEPHEN J. DUBNER and STEVEN D. LEVITT. New York Times. http://www.nytimes.com/2005/06/05/magazine/05FREAK.html?pagewanted=all. Retrieved 2010-08-23. 
  15. ↑ Valderrama, X. et al. (2000). "Seasonal Anointment with Millipedes in a Wild Primate: A Chemical Defense Against Insects?". Journal of Chemical Ecology 26 (12): 2781–2790. doi:10.1023/A:1026489826714. 
  16. ↑ de Waal, F. B., Dindo, M., Freeman, C. A. & Hall, M. J. (2005). "The monkey in the mirror: Hardly a stranger". Proceedings of the National Academy of Sciences Epub ahead of print (32): 11140–7. doi:10.1073/pnas.0503935102. PMID 16055557. 
  17. ↑ Kuroshima, Hika; Kazuo Fujita, Akira Fuyuki, Tsuyuka Masuda (March 2002). "Understanding of the relationship between seeing and knowing by tufted capuchin monkeys (Cebus apella)". Animal Cognition 5 (1): 41–48. doi:10.1007/s10071-001-0123-6. ISSN 1435-9448. PMID 11957401. http://www.springerlink.com/index/ELTR6PV6B8RVTPDA.pdf. 
  18. ↑ Heyes, C. M. (1998). "Theory Of Mind In Nonhuman Primates". Behavioral and Brain Sciences 21. doi:10.1017/S0140525X98000703. bbs00000546. http://www.bbsonline.org/documents/a/00/00/05/46/index.html. 
  19. ↑ 19.0 19.1 Lineberry, C.. "Capuchin Monkeys, Spinal Cord Injuries, Volunteering, Trained Monkeys". AARP. http://www.aarp.org/makeadifference/volunteer/articles/monkey_do.html. Retrieved 2008-10-13. 

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