Human Evolution

, 1:77 | Cite as

On the origins of body size dimorphism in primates

  • M. Pickford


Among many explanations concerning the origins of dimorphism in Primates, none has received as little attention as the differences in energy requirements of the two sexes. It is hypothesised that among Primates, a common strategy for overcoming the extra metabolic load of pregnency and lactation experienced by females during the greater part of their adult lifetimes, is for them to reduce their bodyweights relative to those of males. Such a strategy allows the mother plus infant combination to weight approximately as much as the species target weight or slightly less, preserving the balance between the species and the environment.

Once such body weight dimorphysm had evolved, they might secondarily lead to modifications in behaviour in the species. For example, the now relatively larger males might take on the role of troop protection as a result of their larger size. Such secondarily acquired social and behavioural roles would be expected to show a reasonably strong correlation with the existence of sexual size dimorphism in Primates, even though they may not have been the cause of the dimorphism, but only the result of it. It is evident however, that many dimorphic features in Primates, such as pelage differences, and differential canine size, have been the subject of different selection processes from those which led to the acquisition of differential body size.

Key words

dimorphism differential dimorphisms target weight energy requirement lactation bimaturation 


  1. Altmann S. &Altmann J., 1970. —Baboon ecology: African field research. Bibliotheca primatol., 12: 1–220.Google Scholar
  2. Brown J., 1975. —Geographical ecology of desert rodents. InCody M., andDiamond J., (eds.) Ecology and evolution of communities. Belknap Press, Harvard, Cambridge Mass: 315–341.Google Scholar
  3. Coelho A., 1974. —Socio-bioenergetics and sexual dimorphism in Primates. Primates, 15: 263–269.CrossRefGoogle Scholar
  4. Crook J. &Gartlan J., 1966. —On the evolution of primate societies. Nature, 210: 1200–1203.CrossRefGoogle Scholar
  5. Darwin C., 1871. —The descent of man, and selection in relation to sex. 2 vols London: John Murray.Google Scholar
  6. Dean M. &Wood B., 1981. —Developing pongid dentition and its use for ageing individual crania in comparative cross-sectional growth studies. Folia Primatol., 36: 111–127.CrossRefGoogle Scholar
  7. De Vore J. &Wasburn S., 1963. —Baboon ecology and Human Evolution. In (Howell F. andBorliere F. eds) African Ecology and Human Evolution. p. 335. Chicago: Aldine.Google Scholar
  8. Fleagle J., 1985. —Size and adaptation in Primates. In (Jungers W. ed.)Size and scaling in Primate Biology, pp. 1–19. Plenum, New York.Google Scholar
  9. Fossey D., 1983. —Gorillas in the mist. Hodder and Stroughton. London.Google Scholar
  10. Gaulin S. &Sailer L., 1984. —Sexual dimorphism in weight among the primates. the relative impact of allometry and sexual selection. Int. JI. Primatol., 5: 515–535.Google Scholar
  11. Greenfield L., 1972. —Sexual dimorphism in Dryopithecus africanus Primates, 13: 395–410.CrossRefGoogle Scholar
  12. Harvey P. &Bennett P., 1985. —Sexual dimorphism and reproductive strategies. In (Ghesquiere J., Martin R. andNewcombe F., eds.) Human Sexual Dimorphism: 43–59. Taylor and Francis, London.Google Scholar
  13. Goodall J., 1979. —Life and death at Gombe. Nat. Geogr. 155, (5): 592–621.Google Scholar
  14. Harvey P. &Clutton-Brock T., 1985. —Life History Variation in Primates. Evolution, 39: 559–581.CrossRefGoogle Scholar
  15. Harvey O., Kavanagh M. andClutton-Brock T., 1978. —Sexual dimorphism in primate teeth. Jl. Zool. London, 186: 475–485.CrossRefGoogle Scholar
  16. Leutenegger W. &Cheverud J., 1982. —Correlates of sexual dimorphism in Primates: ecological and size variables. Int. Jl. Primatol., 3: 387–402.Google Scholar
  17. Leutenegger W. &Kelly J., 1977. —Relationships of sexual dimorphism in canine size and body size to social, behavioural and ecological correlates in anthropoid primates. Primates, 18: 117–136.CrossRefGoogle Scholar
  18. Mayr E., 1972. —Sexual selection and natural selection. In (Campbell B., ed.) Sexual selection and the descent of man. Heinemanns, London: 87–104.Google Scholar
  19. Phillips-Conroy J. &Jolly C., 1981. —Sexual dimorphism in two subspecies of Ethiopian baboons (Papio hamadryas) and their hybrids. Am. Jl. Phys. Anthropol., 56: 115–129.CrossRefGoogle Scholar
  20. Pilbeam D.R., 1969. —Tertiary Pongidae of East Africa: Evolutionary relationship and Taxonomy. Bull. Peabody Mus. Nat. Hist., 31: 1–185.Google Scholar
  21. Schultz A., 1969. — The life of Primates, New York, Universe Press.Google Scholar
  22. Shea B., 1983. —Allometry and beterochrony in the African Apes. Am. Jl. Phys. Anthropol., 62: 275–289.CrossRefGoogle Scholar
  23. Shea B., 1983. —Phyletic size change and Brain/Body allometry: A consideration based on the African pongids and other primates. Int. Jl. Primatol., 4: 33–62.Google Scholar
  24. Shea B., 1985. —The ontogeny of sexual dimorphism in the African Apes. Am. Jl. Primatol., 8: 183–188.CrossRefGoogle Scholar
  25. Willner L. &Martin R., 1985. —Some basic principles of mammalian sexual dimorphism. In (Ghesquiere J., Martin R. andNewcombe F. eds.) Human Sexual Dimorphism: 1–42. Taylor and Francis London.Google Scholar

Copyright information

© Editrice II Sedicesimo 1986

Authors and Affiliations

  • M. Pickford
    • 1
  1. 1.Dept PalaeontologyJohannes-Gutenberg-Universität MainzMainzWest Germany

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