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African Wild Ass (Equus africanus) & Domesticated Donkey (Equus asinus) Fact Sheet: Physical Characteristics

Physical Characteristics

Attribute Male/Female Average
Body Weight 275 kg (606 lb)
Head/Body Length 200 cm (6.6 ft)
Tail Length 42 cm (17 in)
Shoulder Height* 125 -145 cm (4.1-4.8 ft)

*Domestic breeds vary in height at shoulder: 80-150 cm (2.6-4.9 ft)

General Appearance


  • Equus africanus somaliensis (Somali wild asses) have dark barring on legs; patterns vary geographically.
    • [Equus asinus (donkeys). A small, short- legged equid with exceptionally long ears.]
  • 40-42 teeth (6 upper incisors, 6 lower; 2 canines upper jaw, 2 lower; 6 or 8 premolars upper jaw, 6 lower; 6 molars upper jaw, 6 lower)
    • Simpler molar tooth pattern for donkeys and asses compared to caballine horses. (Bennett 1980)


  • Short, smooth gray or brown coat with dark stripe down center of back; stripe may not be continuous
  • Underside lighter; legs may have bands.
  • No white on rump. (Grinder et al 2006) 

Sexual Dimorphism

  • Very little sexual dimorphism

Other Characteristics

  • Mane is upright, long, and thin; no forelock
  • Tail is tufted.
  • Hooves are the narrowest of any equid and quite small; these animals are very sure-footed as a result
  • Somali wild asses ears 187-200 mm (7.4-7.9 in) (Groves & Ryder 2000)
    • Donkey ears 200 mm (7.9 in) or longer (Grinder et al 2006)
  • Adaptations to extreme heat in desert environments include ability to raise body temperature by as much as 6.5 ° C (11.7 F°) (Moehlman 1998)
  • Donkeys have 62 chromosomes (domestic horses have 64)

African Wild Ass

a young wild ass with a tuffed tail and gray coat

Tuffed tail with a short, smooth gray coat.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Page Citations

Bennett (1980)
Grinder et al (2006)
Moehlman (1998)
Nowak (1999)

SDZWA Library Links