AAT, scavenging, tool-using, and savannah

Phillip Bigelow (n8010095@henson.cc.wwu.edu)
Fri, 13 Jan 1995 10:35:57 GMT

Recently, there has been quite a lot of rubbish posted on this thread that
tool-using and scavenging skills were developed during some type of
"aquatic" stage, prior to the period of hominid migration to the savannah.
According to the AAT proponents, early aquatic hominids developed the skill
of cracking open mollusks and other sea-shore shelled creatures. This
behavioral adaptation was then later carried over to the savannah-phase,
where, instead of smashing clams, bones of savannah animals were broken open
to expose the marrow as a food source. AAT proponents give the impression
that scavenging and tool use on the savannah is uniquely an "aquatic phase"
and a post-"aquatic-phase" trait of hominids.

This claim is essentially bunk.
Here are a few references that show otherwise:

1) Wild chimpanzees are observed to transmit the behavioral trait of using
rocks to crack open nuts to other chimpanzees in a social group.

Boesch, C. 1993. Aspects of transmission of tool-use in wild
chimpanzees. _in_ Gibson, K.R., and Ingold, T., (eds.), Tools,
Language and Cognition in Human Evolution. Cambridge University
Press, 483 pages.

2) Comparisons with data from Goodall (1968, 1986) and Nishida (1968) on
grouping patterns of chimpanzees from Gombe and Mahale regions of Africa,
indicate that many troops live in more open forests that grade into

Boesch, C. 1991. The effects of leopard predation on grouping patterns
in forest chimpanzees. _Behaviour_, vol. 117 (3-4), pp. 220-242.

3) Forest chimps, on the other hand, have been observed using branches as
clubs to chase away leopards.

Boesch, C. 1991. The effects of leopard predation on grouping patterns
in forest chimpanzees. _Behaviour_, vol. 117 (3-4), pp. 220-242.

4) Chimpanzees use twigs to "fish" for termites in termite mounds.

McGrew, W. C., and Marchant, L.F. 1992. Chimpanzees, tools, and
termites: hand preference or handedness? _Current Anthrpology_,
vol. 33 (1), pp. 114-119.

5) "During observations at the Gombe National Park in western Tanzania,
chimpanzees (Pan troglodytes) were seen taking meat from baboons on 5
occassions and on other occasions evidence strongly suggested that
appropriations had taken place (i.e., stolen by the chimps). Prey animals
involved infant bushbuck and a guinea fowl. From the information collected
to date, it appears that the appropriations (stealing) made by the
chimpanzees may represent an appreciable number of the baboons total
successful hunts per year." In other words, the baboons were making kills
of savannah animals, such as bushbuck, and the chimps would move in and
scavenge the carcasses. This is similar to the scavenging scenarios
proposed for H. erectus on the savannah.

Morris, K., and Goodall, J. 1977. Competition for meat between
chimpanzees and baboons of the Gombe National Park.
_Folia Primatologica_, vol. 28 (2), pp. 109-121.

Let's put to rest the false claims by Morgan and her supporters that early
hominids were poorly-adapted to scavenging behavior, or were totally
unsuited for savannah survival. If our sister clade, the genus Pan, shows
these character traits, then scavenging, tool use, and existence along the
edges of savannah is probably a primitive trait the common ancestor of chimps
and hominids possessed. If the common ancestor possessed these behavior
traits, then the traits pre-date Morgan's hypothesized "aquatic stage".

Frankly, I think this information would go nicely in a FAQ.