White-eared titi

White-eared titi[1][2]
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Pitheciidae
Genus: Callicebus
Species: C. donacophilus
Binomial name
Callicebus donacophilus
(d'Orbigny, 1836)
White-eared titi range

The white-eared titi (Callicebus donacophilus), also known as the Bolivian titi or Bolivian gray titi, is a species of titi, a type of New World monkey, from eastern Bolivia and a small area of Brazil.[1][3] The species has a range that extends east from the Manique River in Beni Department, Bolivia to southern Rondônia in Brazil. Its southern range includes forests around the city of Santa Cruz de la Sierra.

It is a medium-sized monkey with a grey back, orange underside and distinctive white ear tufts. It has an omnivorous diet, eating fruits, other plant materials and invertebrates. It is predated upon primarily by raptors, though felids and other monkey species have been known to attack the species. It is a monogamous species and lives in small groups of two to seven individuals consisting of the pair and their offspring. The species maintains a home range of 1.5 to 3 kilometres (0.93 to 1.9 mi) and has a complex vocal repertoire to maintain their territory. It is also known for its characteristic entwining of tails when groups are sitting together. White-eared titis live for more than 25 years.

The white-eared titi population has a declining trend. The decline is believed to be caused by human-induced habitat loss and degradation, hunting, and capture to be kept as pets. In 2008, the International Union for Conservation of Nature (IUCN) classified the species as Least Concern.

Contents

Taxonomy

The white-eared titi belongs to the New World monkey family Pitheciidae, which contains the titis, saki monkeys, bearded sakis and uakaris. It is a member of the subfamily Callicebinae, of which the only extant genus is Callicebus, containing all of the titi monkeys.

Although the exact position of species within the Callicebus genus is debated,[4] the white-eared titi has been placed within the subgenus Callicebus[1] in the C. donacophilus group with the Rio Beni titi, Rio Mayo titi, Ollala Brothers' titi, and white-coated titi.[4] The white-coated titi (C. pallescens) has sometimes been considered a subspecies of the white-eared titi,[5] but they are treated as separate species in the latest edition of Mammal Species of the World.[1]

Anatomy and physiology

The white-eared titi is a medium-sized primate with grey to orange pelage. The species does not exhibit sexual dimorphism; the male's head and body length averages 311 millimetres (12.2 in) while females average 340 millimetres (13 in).[5] The white-eared titi's tail is longer than the head and body combined.[5] It typically has thick fur, with body and limbs that range from grey agouti to orange agouti with an orange underside and white ear tufts.[6]

Body weight is variable, ranging from around 800 to 1,200 grams (1.8 to 2.6 lb), with the female generally a little lighter.[6] It has been known to live to 25 years old.[7]

Locomotion

The white-eared titi is arboreal, spending most of its time in the lower levels of the forest. It often leaps small distances between trees due to the discontinuous nature of the lower levels; these leaps are not more than several body lengths.[8] The titi monkey is also known to enter the main canopy[8][9] and may travel along the ground, though the later is rare.[10][11] When travelling on the ground it is said to use a "bounding movement"[6] whereby it leaps more than 1 metre (3.3 ft) off the ground.[10][11] During normal movement through its environment it walks, clambers and leaps, it also bounds and climbs.[9] The titi monkey prefers branches which are less than 5 centimetres (2.0 in) in diametre and its tail never touches the support they are on.[9][12]

Behaviour

Social structure

The white-eared titi is cryptic, diurnal and known to live in small family groups.[11][13] It is a monogamous species that is thought to mate for life and lives in groups of 2 to 7 individuals consisting of a pair of adults and their offspring.[14][15][16][17] Multi-male groups have also been recorded.[18] Between the ages of two to four years, offspring will disperse from the natal group, with females dispersing earlier than the males.[17][19]

There is a strong bond between the adult monogamous pair, they stay close and carry out activities together.[20][21][22][23] The pair will often huddle, intertwine tails, groom each other and hold hands. They have also been seen to foot grasp, lip-smack, nuzzle, gently grasp one another and sit pressed together. When confronted with a strangers the will respond agonistically together.[20][22][24][25] When separated, the pair show a significant amount of distress and agitation.[26]

References

  1. ^ a b c d Groves, C. (2005). Wilson, D. E., & Reeder, D. M, eds. ed. Mammal Species of the World (3rd ed.). Baltimore: Johns Hopkins University Press. pp. 143. OCLC 62265494. ISBN 0-801-88221-4. http://www.bucknell.edu/msw3/browse.asp?id=12100329. 
  2. ^ "Callicebus donacophilus". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=572965. Retrieved 28 November 2006. 
  3. ^ a b Veiga, L. M., Wallace, R. B. & Ferrari, S. F. (2008). Callicebus donacophilus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 3 January 2009.
  4. ^ a b van Roosmalen, M. G. M., van Roosmalen, T. and Mittermeier, R. A. (June 2002). "A Taxonomic Review of the Titi Monkeys, Genus Callicebus Thomas, 1903, With the Description of Two New Species, Callicebus bernhardi and Callicebus stephennashi, from Brazilian Amazonia". Neotropical Primates 10: 1–52. 
  5. ^ a b c Hershkovitz P. (1990). "Titis, new world monkeys of the genus Callicebus (Cebidae, Platyrrhini): a preliminary taxonomic review". Fieldiana Zoology 55: 1–109. 
  6. ^ a b c Gron, K. J. (2007-12-19). "Primate Factsheets: Dusky titi (Callicebus moloch) Taxonomy, Morphology, & Ecology". http://pin.primate.wisc.edu/factsheets/entry/dusky_titi/taxon. Retrieved 2010-04-10. 
  7. ^ Weigl, R. (2005). Longevity of mammals in captivity; from the living collections of the world. Stuttgart: E. Schweizerbartsche. pp. 214. 
  8. ^ a b Lawler, R. R., Ford, S. M., Wright, P. C. & Easley, S. P. (2006). "The locomotor behavior of Callicebus brunneus and Callicebus torquatus". Folia Primatologica 77 (3): 228–39. doi:10.1159/000091232. 
  9. ^ a b c Youlatos, D. (1999). "Comparative locomotion of six sympatric primates in Ecuador". Annales Des Sciences Naturelles 20 (4): 161–168. 
  10. ^ a b Erwin, J., Maple, T. L. & Mitchell, G., ed (1979). "Titi and squirrel monkeys in a novel environment". Captivity and behavior: Primates in breeding colonies, laboratories, and zoos.. New York: Van Nostrand Reinhold. pp. 172–216. 
  11. ^ a b c Kinzey, W. G. (1981). "The titi monkeys, genus Callicebus: I. description of the species". In Coimbra-Filho, A. F. & Mittermeier, R. A.. Ecology and behavior of neotropical primates, Vol. 1. Rio de Janeiro: Academia Brasileira de Ciências. pp. 241–276. 
  12. ^ Welker, C., Jantschke, B. & Klaiber-Schuh, A. (1998). "Behavioural data on the titi monkey Callicebus cupreus and the owl monkey Aotus azarae boliviensis. A contribution to the discussion on the correct systematic classification of these species. Part I: introduction and behavioural differences". Primate Report 51: 3–18. 
  13. ^ Eisenberg, J. F. & Redford, K. H. (1999). Mammals of the Neotropics, Vol. 3: The Central Neotropics.. Chicago: University of Chicago Press. 
  14. ^ Wright, P. C. (1984). "Ecological correlates of monogamy in Aotus and Callicebus". In Else, J. G. & Lee, P. C.. Primate ecology and conservation. Cambridge: Cambridge University Press. pp. 159–167. 
  15. ^ Mason, W. A. & Mendoza, S. P. (1993). Contrasting life modes in cebidae: titi monkeys (Callicebus) and squirrel monkeys (Saimiri). AAZPA Reg Conf Proceed (1993). pp. 715–722. 
  16. ^ Kinzey, W. G. (1997). "Synopsis of the new world primates: Callicebus". In Kinzey, W. G.. New world primates: ecology, evolution, and behavior. New York: Aldine De Gruyter. pp. 213–221. 
  17. ^ a b Bossuyt, F. (2002). Natal dispersal of titi monkeys (Callicebus moloch) at Cocha Cashu, Manu national park, Peru. 34. American Journal of Physical Anthropology. pp. 47. 
  18. ^ Bicca-Marques, J. C., Garber, P. A. & Azevedo-Lopes, M. A. O. (2002). Evidence of three resident adult male group members in a species of monogamous primate, the red titi monkey (Callicebus cupreus). 66. Mammalia. pp. 138–142. 
  19. ^ Wright, P. C. (1985). The costs and benefits of nocturnality for Aotus trivirgatus (the night monkey). PhD dissertation. City University of New York. pp. 315. 
  20. ^ a b Mason, W. A. (1966). "Social organization of the South American monkey, Callicebus moloch: a preliminary report". Tulane Stud Zool 13: 23–28. 
  21. ^ Cubicciotti, D. D. & Mason, W. A. (1978). "Comparative studies of social behavior in Callicebus and Saimiri: heterosexual jealousy behavior.". Behav Ecol Sociobiol 3: 311–322. doi:10.1007/BF00296316. 
  22. ^ a b Anzenberger, G., Mendoza, S. P. & Mason, W. A. (1986). "Comparative studies of social behavior in Callicebus and Saimiri: behavioral and physiological responses of established pairs to unfamiliar pairs". American Journal of Primatology 11 (1): 37–51. doi:10.1002/ajp.1350110105. 
  23. ^ Mendoza, S. P., Reeder, D. M. & Mason, W. A. (2002). "Nature of proximate mechanisms underlying primate social systems: simplicity and redundancy". Evolutionary Anthropology 11 (1): 112–116. doi:10.1002/evan.10071. 
  24. ^ Mason, W. A. (1968). "Use of space by Callicebus". In Jay, P. C.. Primates: studies in adaptation and variability. New York: Holt, Rinehart and Winston. pp. 200–216. 
  25. ^ Fernandez-Duque, E., Mason, W. A. & Mendoza, S. P. (1997). "Effects of duration of separation on responses to mates and strangers in the monogamous titi monkey (Callicebus moloch)". American Journal of Primatology 43 (3): 225–237. doi:10.1002/(SICI)1098-2345(1997)43:3<225::AID-AJP3>3.0.CO;2-Z. PMID 9359966. 
  26. ^ Mendoza, S. P. & Mason, W. A. (1986). "Contrasting responses to intruders and to involuntary separation by monogamous and polygynous new world monkeys". Physiological Behavior 38 (6): 795–801. doi:10.1016/0031-9384(86)90045-4. 

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