Earliest Hominids

Harry Erwin (herwin@gmu.edu)
Sat, 24 Jun 1995 09:39:12 -0400

A summary of what appears to me to be the characteristics of the earliest

Weight: Less than pigmy chimps. Adult females at 40-50 pounds and adult
males at 60-80.

Motility Strategy: arboreal climbing and bridging, terrestrial bipedalism.
Perhaps some skill in fresh water swimming. Arboreal behavior stronger
than in chimps and weaker than in orangs.

Climate: hot.

Environment: treed savanna and gallery forests along water courses. Highly
dependent on access to trees--treeless savanna was too open. Environment
was probably very patchy in terms of supporting hominid groups. If species
recognition characteristics were labile and dominated by behavioral
signals and if groups were territorial, quite likely to have experienced
an explosive radiation in this environment, leading to the marked
variability seen in the fossil record.

Niche: omnivore, concentrating on high quality foods taken on the ground
and from trees. Used arboreal tree-climbing and terrestrial bipedalism to
maximize search rate.

Defense mechanisms: group cooperation and tree climbing. (Females and
juveniles were light enough that leopards could be avoided by moving out
to small branches.) If swimming behavior was present, escape by dropping
into the water might have also been used.

Sexual strategy: TBD, but probably did not involve pair-bonding.

Harry Erwin
Internet: herwin@gmu.edu
Home Page: http://osf1.gmu.edu/~herwin (try again if necessary)
PhD student in comp neurosci: "Glitches happen" & "Meaning is emotional"