Pitheciidaetiti monkeys, sakis, and uakaris

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Diversity

There are 40 species in the family Pitheciidae, commonly known as titi monkeys, sakis, and uakaris. The most diverse genus in this family is Callicebus, the titi monkeys, with 28 species. There are 5 species of saki monkeys (Pithecia), 5 species of bearded saki monkeys (Chiropotes), and 2 species of uakaris (Cacajao). (Wilson and Reeder, 2005)

Geographic Range

Titis, sakis, and uakaris are found in the rainforests of South America, including the Amazon and Orinoco river basins and the Atlantic coastal forest of southeastern Brazil. (Grafton, 2004; Nowak, 1991)

Habitat

Titis and sakis are highly arboreal and found in a wide variety of forests, including highland and lowland forests, dry forests, varzea, savanna forests, liana forests, swamps, inundated forests, and forests along river and lake edges. Chiropotes and Cacajao species are restricted to fewer forest types, including terra firme and higher elevation moist and savanna forests. (Grafton, 2004; Nowak, 1991)

Physical Description

Titis, sakis, and uakaris are small to medium-sized monkeys. Titis (Callicebus) are the smallest and uakaris (Cacajao) are the largest. The four pitheciine genera are distinct in appearance, but all share a common dental morphology marked by large, laterally splayed canine teeth separated from the incisors by a diastema. The incisors are also angled forward and the molars have low, crenulated occlusal surfaces. This dental morphology is an adaptation to eating hard, heavily protected fruits. Uakaris (Cacajao) and bearded sakis (Chiropotes) are sexually dimorphic and several saki monkey species (Pithecia) are sexually dichromatic. Pelage color varies from light and thin, in uakaris to dark and woolly in bearded sakis. Uakaris (Cacajao) are the most unusual looking pitheciines, with largely naked faces and heads and short tails, they sometimes have a nearly bald appearance as well. (Grafton, 2004; Nowak, 1991)

Head and body length is 230 to 460 mm in Callicebus, 300 to 705 mm in Pithecia, 327 to 511 mm in Chiropotes, and 300 to 579 mm in g.Cacajao. Tail length is 260 to 560 mm in <<g.Callicebus, 255 to 545 mm in Pithecia, 300 to 507 mm in Chiropotes, and 125 to 210 mm in Cacajao. Callicebus species weigh up to 2 kg, Pithecia species weigh 0.7 to 1.7 kg, Chiropotes species weigh 2 to 4 kg, and Cacajao species weight from 2.7 to 3.5 kg. (Nowak, 1991)

  • Sexual Dimorphism
  • sexes alike
  • male larger
  • sexes colored or patterned differently

Reproduction

Mating systems in titis, sakis, and uakaris are variable. Titi monkeys (Callicebus) live in small groups made up of a monogamous pair and their offspring. All other genera live in multi-male, multi-female groups of various sizes and mating is promiscuous. Saki monkey females (Pithecia) often have help from subadult females in raising their young. (Grafton, 2004; Nowak, 1991)

The reproductive biology of pitheciids is variable. Most species reproduce seasonally and give birth to single offspring, although Pithecia albicans is reported to reproduce throughout the year. Gestation lengths are reported from 150 to 180 days and lactation from 3 to 6 months in titis (Callicebus) or up to 2 years in uakaris Cacajao. Titis are born at approximately 70 grams. Interbirth intervals range from once yearly in titis (Callicebus) to every 2 years in uakaris (Cacajao). Bearded sakis (Chiropotes) become sexually mature at 4 years old and titis (Callicebus) at 3 to 4 years old. Independence is reported at 10 to 13 months in Chiropotes. (Grafton, 2004; Nowak, 1991)

In Pithecia, Chiropotes, and Cacajao species, males do not generally care for their young. Although Pithecia fathers may groom their young and females may have help from subadult females. Callicebus is unusual among New World primates in that males provide the majority of care for young, only returning them to their mothers to nurse. Young are typically carried ventrally for their first few months, after which they are transferred to being carried on the back and begin to locomote on their own away from caregivers. (Grafton, 2004; Nowak, 1991)

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • post-independence association with parents
  • extended period of juvenile learning

Lifespan/Longevity

Titis (Callicebus), the smallest of the pitheciids, have lived more than 25 years in captivity. Uakaris (Cacajao) have lived more than 31 years in captivity and sakis (Pithecia) up to 35 years. Bearded sakis (Chiropotes) are estimated to live more than 18 years in the wild. (Nowak, 1991)

Behavior

Titis, sakis, and uakaris are all diurnal and social monkeys. All are highly arboreal, only rarely coming to the ground. All species use mainly quadrupedal locomotion in the trees, but uakaris (Cacajao) sometimes also employ leaps and bipedal suspension. Sakis and bearded sakis (Pithecia and Chiropotes) have relatively smaller ranges than do the other genera, from 1 to 4.5 km. Uakaris range up to 5 km in a day. (Grafton, 2004; Nowak, 1991)

All pitheciid species live in small groups. Titis live in family groups made up of a mated pair and and their offspring. Other genera live in multi-male, multi-female groups of various sizes, from 10 to 30 in Chiropotes to groups of up to 100 in Cacajao. Territories are defended but there can also be extensive overlap in home ranges of adjacent groups. Territories are most often defended with vocalizations. (Grafton, 2004; Nowak, 1991)

Communication and Perception

Titis, sakis, and uakaris use vocalizations extensively to communicate with conspecifics and defend territorial boundaries. Titi pairs are the most territorial and males emit loud vocalizations to advertise territorial boundaries. Male and female duets are also used to communicate territorial boundaries. Grooming is very important in reinforcing social bonds. In titis (Callicebus) individuals sit together with their tails entwined and may spend up to 10% of their time grooming each other. Chiropotes and Cacajao species exhibit a tail-wagging behavior that shows excitement. Red uakaris, Cacajao calvus, have one of the widest ranges of facial expressions in primates. (Grafton, 2004; Nowak, 1991)

  • Other Communication Modes
  • duets

Food Habits

Titis, sakis, and uakaris are all specialized for eating large, hard fruits, often to get at the seeds within. Titis (Callicebus) eat more fruit pulp than other genera. Sakis and uakaris eat mainly large, indehiscent fruits with few large seeds, such as brazil nuts. Pitheciid species also supplement their diet with leaves and insects. (Grafton, 2004; Nowak, 1991)

Predation

Titis, sakis, and uakaris may be preyed on by large diurnal raptors, who hunt above forest canopies.

Ecosystem Roles

Titis, sakis, and uakaris may help disperse the seeds of some of the fruits they eat.

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

Titis, sakis, and uakaris are hunted for meat and captured for the pet trade. They are important members of native forest ecosystems and can be important in drawing ecotourism interest in an area. (Groves, 2001; Nowak, 1991)

Economic Importance for Humans: Negative

There are no known adverse effects of titis, sakis, and uakaris on humans. (Nowak, 1991)

Conservation Status

Two species of titi monkeys (Callicebus) are critically endangered, C. barbarabrownae and C. coimbrai, both are known only from small forest fragments. Brown bearded sakis, Chiropotes satanus, are endangered as a result of forest fragmentation. All members of Pitheciidae are on CITES Appendix II. (International Union for the Conservation of Nature, 2007)

  • IUCN Red List [Link]
    Not Evaluated

Other Comments

Fossil primates from Miocene and middle Miocene deposits have been aligned with pitheciid genera. (Grafton, 2004)

Contributors

Tanya Dewey (author), Animal Diversity Web.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

cooperative breeder

helpers provide assistance in raising young that are not their own

diurnal
  1. active during the day, 2. lasting for one day.
duets

to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate

ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

food

A substance that provides both nutrients and energy to a living thing.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

frugivore

an animal that mainly eats fruit

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

References

Canavez, F., M. Moreira, J. Ladasky, A. Pissinatti, P. Parham, H. Seuanez. 1999. Molecular Phylogeny of New World Primates (Platyrrhini) Based on ??2-Microglobulin DNA Sequences. Molecular Phylogenetics and Evolution, 12: 74-82.

Grafton, B. 2004. Sakis, Titis, and Uakaris (Pitheciidae). Pp. 143-154 in M Hutchins, D Thoney, M McDade, eds. Grzimek's Animal Life Encyclopedia, Vol. 14. Detroit, Michigan: Thomson Gale.

Groves, C. 2001. Primate Taxonomy. Washington, D.C.: The Smithsonian Institution Press.

Hershkovitz, P. 1977. Living New World Monkeys (Platyrrhini). Chicago: The University of Chicago Press.

Hershkovitz, P. 1988. Origin, Speciation, and Distribution of South American Titi Monkeys, Genus Callicebus (Family Cebidae, Platyrrhini). Proceedings of the Academy of Natural Sciences of Philadelphia, 140: 240-272.

Hershkovitz, P. 1987. The Taxonomy of South American Sakis, Genus Pithecia (Cebidae, Platyrrhini): A Preliminary Report and Critical Review with the Description of a New Species and a New Subspecies. American Journal of Primatology, 12: 387-468.

Hershkovitz, P. 1990. Titis, New World Monkeys of the Genus Callicebus (Cebidae, Platyrrhini): A Preliminary Taxonomic Review. Fieldiana, 55: 1-109.

International Union for the Conservation of Nature, 2007. "2007 IUCN Red List of Threatened Species" (On-line). Accessed November 16, 2007 at http://www.iucnredlist.org/.

Nowak, R. 1991. Walker's Mammals of the World, Volume 1. Baltimore: The Johns Hopkins University Press.

Ray, D., J. Xing, D. Hedges, M. Hall, M. Laborde, B. Anders, B. White, N. Stoilova, J. Fowlkes, K. Landry, L. Chemnick, O. Ryder, M. Batzer. 2005. Alu insertion loci and platyrrhine primate phylogeny. Molecular Phylogenetics and Evolution, 35: 117-126.

Steiper, M., M. Ruvolo. 2003. New World monkey phylogeny based on X-linked G6PD DNA sequences. Molecular Phylogenetics and Evolution, 27: 121-130.

Wilson, D., D. Reeder. 2005. Mammal Species of the World. Baltimore: The Johns Hopkins University Press. Accessed November 16, 2007 at http://nmnhgoph.si.edu/msw/.