Re: Gender differences

Bruce D. Scott (
12 May 1995 13:11:33 GMT

Bryant ( wrote:
: Are humans considered sexually dimorphic in size. My subjective
: impression is that men are taller (not just more robust) than women. Is
: that generally accepted by anthropologists?

Sarah Hrdy states [1], that the sexual dimorphism in present-day humans is
5 to 12 percent, and argues that recent (prior to 1981) finds from Harar
and Laetoli suggest the dimorphism in hominids 4 Myr ago was larger. Phil
Nicholls can possibly post the most recent status of this.

: If so, does it imply behavioral correlates (greater aggression in men)?

Hrdy reviews the correlation of monogamy to size-equality and also polygyny
to size-inequality, citing the earliest studies as well as more recent ones
[2]. One of the other correlations is of size-inequality to inequailty in
male reproductive success (same cites). Probably also of interest is a
review she cites on the evolution of monogamy [3].

[1] S B Hrdy, _The Woman That Never Evolved_ (Harvard, 1981), esp pp 23-24,
and 174-175 (noting the evidence against monogamy in humans).

[2] C Darwin, _Origin of the Species_
T Gill, "The Eared Seal", American Naturalist 4(11):675-684 (1871)
R D Alexander et al, "Sexual dimorphisms and breeding systems in
pinnipeds, ungulates, primates, and humans", in _Evolutionary Biology and
Human Social Organisation_ (Duxbury Press, 1979)
A Gautier-Hion, "Dimorphisme sexual et organisation sociale chez les
cerocopithecines forestiers africains", Mammalia 39:365-374 (1975)
T Clutton-Brock et al, "Sexual dimorphism, socioeconomic sex ratio and
body weight in primates", Nature 269:797-800 (1977)

[3] J F Wittenberger and R L Tilson, "The evolution of monogamy: hypotheses
and evidence", Annual Review of Ecology and Systematics 11:197-232 (1980)

Dr Bruce Scott The deadliest bullshit is
Max-Planck-Institut fuer Plasmaphysik odorless and transparent -- W Gibson