Patas Monkey (Erythrocebus patas) Fact Sheet: Physical Characteristics

Data from Mittermeier et al. 2013

Body Shape (from Isbell 2013 unless otherwise noted)

• Medium sized
• Long-legged, lanky appearance (Groves and Kingdon 2013; Hall 1966)
  • Limbs longer than other similarly sized primates
  • Increased stride length via modifications of the tarsal and metatarsal bones and hind foot digitigrady (Gartlan 1974; Hildebrand 1982; Strasser 1992)
    • Good for high-speed escape from predators (Chism and Rowell 1988; Hall 1965; Isbell 1998; Nakagawa 1999)
    • Increases travel efficiency during long-distance daily foraging (Isbell 1998; Isbell et al. 1998a)
• Feet, long and padded
• Deep-chested
• Torso slender
• Tail arched; carried arched behind the body while walking
  • Not prehensile, incapable of hanging by their tail; feature of all Old World monkeys

Pelage/Coat (from Isbell 2013 and Mittermeier et al. 2013 unless otherwise noted)

• Variable between individuals, sexes, and age classes (Hall 1966)
• Adults
  • Crown of head reddish-brown
    • Lighter brown in some (Hall 1966)
    • Mixed with gray in older adults (Hall 1966)
  • Back and flanks reddish
  • Underparts cream or white
    • Nearly white in most males; less contrasted in females (Hall 1966)

Facial Characteristics

• Vary by regional type (Hall 1966)
• Subspecies characterized by differences in male's facial features (summarized from Isbell 2013 and Mittermeier et al. 2013):

• Nose of female turns progressively lighter with age, until all white at c. 3 yrs (Isbell et al. 2009)

Dimorphic in size and color

• Male larger are more distinctly colored
  • c.twice as heavy as females (Hall 1966; Isbell 2013)
    • Onset of weight differences early; apparent in male at 18 months of age (Hall 1966)
  • Coat more contrasted and shaggier (Hall 1966; Isbell 2013; Mittermeier et al. 2013)
  • Canine teeth nearly twice the length than those of females (Carlson and Isbell 2001)
  • Scrotum turquoise or aquamarine blue (Bercovitch 1996; Hall 1966; Isbell 2013)
    • As with vervets (Cercopithecus aethiops) (Hall 1966)
    • Not influenced by reproductive seasonality (i.e. testosterone independent), body weight, or health (Bercovitch 1996)
  • Anus red (Isbell 2013)
• Female tail has a less pronounced arch (Isbell 2013)

Physiological Adaptations

• Digestive tract
• Specialized for digesting foods high in soluble fiber, similar to vervets
• Typical of a diet heavy on plant material
• Large colon with symbiotic cellulolytic bacteria and high concentrations of fatty acids enable digestion, including tree gum rich in polysaccharides (Isbell et al. 2013)
• Long food retention time, slows digestion and increases absorption (Isbell et al. 2013)
• Thermoregulation
  • Numerous sweat glands on palms, chest and legs (Gisolfi et al. 1982)
  • Efficiently maintain body temperature within a narrow range across a wide range of ambient temperatures (Kolka and Elizonda 1983)
  • Juveniles unable to maintain body temperatures as effectively as adults

Chromosome Number

• 27 pairs (2n=54) (Groves and Kingdon 2013)

Eastern Patas Monkey (Adult Female). Image credit: © Rob Gipman. Photograph taken in Uganda at Murchison Falls National Park. From Flickr. Some rights reserved.

Western Patas Monkey (Adult Male). Image credit: © Ucumari. Photograph taken at the North Carolina Zoo. From Flickr. Some rights reserved.

These terrestrial monkeys are well adapted to life on the ground. Their long legs enhance their travel efficiency, good for high speed escape or long-distance foraging. Subspecies are identified by geographical location and by distinctive facial features of males. Eastern patas have a prominent white spot on top of their noses, while southern patas lack the white moustache seen in the eastern and western subspecies.

Bercovitch (1996)

Carlson and Isbell (2001)

Chism and Rowell (1988)

Gartlan (1974)

Gisolfi et al. (1982)

Groves and Kingdon (2013)

Hall (1965)

Hildebrand (1982)

Isbell (1998)

Isbell (2013)

Isbell et al. (1998a,b)

Isbell et al. (2009)

Isbell et al. (2013)

Kolka and Elizonda (1983)

Nakagawa (1999)

Mittermeier et al. (2013)

Strasser (1992)