Capuchin monkey

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Capuchin
Temporal range: 6.2–0 Ma
Late Miocene – Recent
Capuchin Costa Rica.jpg
White-headed capuchin (Cebus capucinus)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Cebidae
Subfamily: Cebinae
Bonaparte, 1831
Genus

Cebus
Sapajus

The capuchin monkeys (/ˈkæpjʊɪn/ or /ˈkæpjʊʃɪn/) are New World monkeys of the subfamily Cebinae. Prior to 2011, the subfamily contained only a single genus, Cebus. However, in 2011, it was proposed that the capuchin monkeys should be split between the gracile capuchins in the genus Cebus and the robust capuchins in the genus Sapajus. The range of capuchin monkeys includes Central America and South America as far south as northern Argentina.

Etymology[edit]

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 friars 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 comes from the Greek word kêbos,[3] meaning a long-tailed monkey.

Classification[edit]

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]

In 2011, Jessica Lynch Alfaro et al proposed that the robust capuchins (formerly the C. apella group) be placed in a separate genus, Sapajus, from the gracile capuchins (formerly the C. capucinus group) which retain the Cebus genus.[8][9] Other primatologists, such as Paul Garber, have begun using this classification.[10]

According to genetic studies led by Lynch Alfaro in 2011, the gracile and robust capuchins diverged approximately 6.2 million years ago. Lynch Alfaro suspects that the divergence was triggered by the creation of the Amazon River, which separated the monkeys in the Amazon north of the Amazon River, which evolved into the gracile capuchins, from those in the Atlantic Forest south of the river, which evolved into the robust capuchins. Gracile capuchins have longer limbs relative to their body size than robust capuchins. Gracile capuchins have rounder skulls, whereas robust capuchins have jaws better adapted for opening hard nuts. Robust capuchins have crests and the males have beards.[8][9]

Tufted capuchin (Sapajus apella)

* Rediscovered species.[12]

Physical characteristics[edit]

Capuchins are black, brown, buff or whitish, but their exact color and pattern depends on the species involved. They reach a length of 30 to 56 cm (12–22 in), with tails that are just as long as the body.

Behavior[edit]

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.

White-fronted capuchin (Cebus albifrons)

Diet[edit]

The capuchin monkey feeds on a vast range of food types, and is more varied than other monkeys in the family Cebidae. They are omnivores, and consume a variety of plant parts such as leaves, flower and fruit, seeds, pith, woody tissue, sugarcane, bulb, and exudates, as well as arthropods, molluscs, a variety of vertebrates, and even primates.[13] Capuchins have been observed to also be particularly good at catching frogs.[14] They are characterized as innovative and extreme foragers because of their ability to acquire sustenance from a wide collection of unlikely food, which may assure them survival in habitats with extreme food limitation.[15] Capuchins living near water will also eat crabs and shellfish by cracking their shells with stones.[16]

Social structure and Habitat[edit]

Capuchin monkeys inhabit a large range of Brazil and other parts of Latin and Central America. Capuchin monkeys often live in large groups of 10 to 35 individuals within the forest, although they can easily adapt to places colonized by humans. Usually, a single male will dominate the group, and they have primary rights to mate with the females of their group. However, the white-headed capuchin groups are led by both an alpha male and an alpha female.[17] Each group will cover a large territory, since members must search for the best areas to feed. These primates are territorial animals, distinctly marking a central area of their territory with urine and defending it against intruders, though outer areas may overlap. The stabilization of group dynamics is served through mutual grooming, and communication occurs between the monkeys through various calls.[18] Capuchins can jump up to nine feet (three meters), and they use this mode of transport to get from one tree to another. They remain hidden among forest vegetation for most of the day, sleeping on tree branches and descending to the ground to find drinking water.

Mating[edit]

Capuchin females often direct most of their proceptive and mating behavior towards the alpha male. However, when the female reaches the end of her proceptive period, she may sometimes mate with up to six different subordinate males in one day.[19] Strictly targeting the alpha male does not happen every time, as some females have been observed to mate with three to four different males.[20] When an alpha female and a lower-ranking female want to mate with an alpha male, the more dominant female will get rights to the male over the lower-ranking one.

Life history[edit]

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. Juveniles become fully mature within four years for females and eight years for males. In captivity, individuals have reached an age of 45 years, although natural life expectancy is only 15 to 25 years.

Threats[edit]

Capuchin monkeys are clever and easy to train. As a result, they are used to help people who are quadriplegics in many developed countries. They have also become popular pets and attractions for street entertainment, and are hunted for meat by local people. Since they have a high reproductive rate and can easily adapt to their living environment, loss of the forest does not negatively impact the capuchin monkey populations as much as other species, although habitat fragmentation is still a threat.[21] Natural predators include jaguars, cougars, jaguarundis, coyotes, tayras, snakes, crocodiles and birds of prey. The main predator of the tufted capuchin is the harpy eagle, which has been seen bringing several capuchins back to its nest.[22]

Intelligence[edit]

Crested capuchin (Sapajus robustus)

Capuchins are considered the most intelligent New World monkeys[23] 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[citation needed]. 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[citation needed]. 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[citation needed]. Young capuchins will watch this process to learn from the older, more experienced adults but it takes them 8 years to master this.[24]

In 2005, experiments were conducted on the ability of capuchins to use money[citation needed]. After several months of training, the monkeys began exhibiting behaviors considered to reflect understanding of the concept of a medium of exchange that were previously believed to be restricted to humans (such as responding rationally to price shocks)[citation needed]. They showed the same propensity to avoid perceived losses demonstrated by human subjects and investors[citation needed]. They also trade sex for money.[25]

During the mosquito season, they crush millipedes and rub the result on their backs. This acts as a natural insect repellent.[26]

Self-awareness[edit]

Further information: 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 do not 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, while 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.[27]

Theory of mind[edit]

Main article: 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.[28] This has, however, been repudiated as conclusive evidence for a theory of mind as the monkeys may have learned to discriminate knower and guesser by other means.[29] Until recently it was believed that non-human great apes did not possess a theory of mind either, although recent research indicates this may not be correct.[30] Human children commonly develop a theory of mind around the ages 3 and 4.

Relationship with humans[edit]

19th-century organ grinder and his capuchin monkey

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".[31] One organization has 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 fetching objects, turning lights on and off, and opening drink bottles.[31]

In 2010, the U.S. federal government revised its definition of service animal under the Americans with Disabilities Act (ADA). Non-human primates are no longer recognized as service animals under the ADA.[32] The American Veterinary Medical Association does not support the use of nonhuman primates as assistance animals because of animal welfare concerns, the potential for serious injury to people, and risks that primates may transfer dangerous diseases to humans.[33]

References[edit]

  1. ^ a b c Fragaszy et al. (2004). The complete capuchin : the biology of the genus Cebus. Cambridge University Press. p. 5. ISBN 978-0-521-66116-4. 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. ISBN 0-548-93307-3. 
  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. ^ a b 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. ^ a b Lynch Alfaro, J.W. et al. (2011). "Explosive Pleistocene range expansion leads to widespread Amazonian sympatry between robust and gracile capuchin monkeys" (PDF). Journal of Biogeography. doi:10.1111/j.1365-2699.2011.02609.x. 
  9. ^ a b c Lynch Alfaro, J.W.; Silva, j. & Rylands, A.B. (2012). "How Different Are Robust and Gracile Capuchin Monkeys? An Argument for the Use of Sapajus and Cebus". American Journal of Primatology: 1–14. doi:10.1002/ajp.222007. 
  10. ^ Garber, P.A., Gomes, D.F. & Bicca-Marquez, J.C. (2011). "Experimental Field Study of Problem-Solving Using Tools in Free-Ranging Capuchins (Sapajus nigritus, formerly Cebus nigritus)" (PDF). American Journal of Primatology 73 (4): 1–15. doi:10.1002/ajp.20957. PMID 21538454. 
  11. ^ Groves, C.P. (2005). Wilson, D.E.; Reeder, D.M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press. pp. 136–138. OCLC 62265494. ISBN 0-801-88221-4. 
  12. ^ 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.  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. 
  13. ^ Izawa K (1979) Foods and feeding behaviour of wild black-capped capuchin (Cebus apella). Primates 20:57–76
  14. ^ Izawa K (1979) Foods and feeding behaviour of wild black-capped capuchin (Cebus apella). Primates 20:57–76
  15. ^ Fragaszy DM, Visalbergui E, Fedigan LM (2004) Behavioral ecology: how do capuchins make a living?
  16. ^ 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.
  17. ^ Ferrari SF, Iwanaga S, Ravetta AL, Freitas FC, Sousa BAR, Souza LL, Costa CG, Coutinho PEG (2003) Dynamics of primate communities along the Santarém-Cuiabá highway in southern central Brazilian Amazonia. In: Marsh LK (ed) Primates in fragments. Kluwer, New York, pp 123–144
  18. ^ Sarie Van Belle, Alejandro Estrada and Paul A. Garber Journal: Behavioral Ecology and Sociobiology, 2013, Volume 67, Number 1, Page 31
  19. ^ Janson, C. H. (1984). Female choice and mating system of the brown capuchin monkey Cebus apella (Primates: Cebidae). Z. Tierpsychol. 65, 177–200
  20. ^ Lynch, J. W. (1998). Mating behavior in wild tufted capuchins (Cebus apella nigritus) in Brazil’s Atlantic forest. Am. J. Phys. Anthropol. Suppl. 26, 153.
  21. ^ Sanz V, Márquez L (1994) Conservación del mono capuchino de Margarita (Cebus apella margaritae) en la Isla de Margarita, Venezuela. Neotrop Primates 2(2):5–8
  22. ^ Fragaszy et al. (2004). The complete capuchin : the biology of the genus Cebus. Cambridge University Press. p. 5.
  23. ^ "Black-faced Capuchin". Amazonian Rainforest. Monkey Jungle. Retrieved 2008-10-13. [unreliable source?]
  24. ^ 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. 
  25. ^ Dubner, Stephen J.; Levitt, Steven D. (2005-06-05). "Monkey Business". Freakonomics column. New York Times. Retrieved 2010-08-23. 
  26. ^ 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. 
  27. ^ 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 102 (32): 11140–7. doi:10.1073/pnas.0503935102. PMC 1183568. PMID 16055557. 
  28. ^ Kuroshima, Hika; Kazuo Fujita; Akira Fuyuki; Tsuyuka Masuda (March 2002). "Understanding of the relationship between seeing and knowing by tufted capuchin monkeys (Cebus apella)" (PDF). Animal Cognition 5 (1): 41–48. doi:10.1007/s10071-001-0123-6. ISSN 1435-9448. PMID 11957401. 
  29. ^ Heyes, C. M. (1998). "Theory Of Mind In Nonhuman Primates". Behavioral and Brain Sciences 21. doi:10.1017/S0140525X98000703. bbs00000546. 
  30. ^ Jabr, Ferris. "Clever critters: Bonobos that share, brainy bugs and social dogs". Scientific American. Retrieved 8 June 2010. 
  31. ^ a b Lineberry, C. "Capuchin Monkeys, Spinal Cord Injuries, Volunteering, Trained Monkeys". AARP. Retrieved 2008-10-13. 
  32. ^ "Highlights of the Final Rule to Amend the Department of Justice's Regulation Implementing Title II of the ADA". United States Department of Justice-Civil Rights Division. Retrieved October 2, 2013. 
  33. ^ "AVMA Animal Welfare Division Director's Testimony on the Captive Primate Safety Act". American Veterinary Medicine Association. Retrieved October 2, 2013. 

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