In the late twentieth century humans developed a new
respect for
chimpanzee culture. A survey published in 1999 listed no fewer than
thirty-nine items of chimpanzee behavior in the wild that seemed to be
culturally transmitted. For example, some chimpanzee populations have a
technique for cracking nuts with stones-more precisely, they place the
nut on one stone and break it with another. Chimpanzees are not
genetically programmed to do this; all they get from their genes is the
capacity to acquire the skill, normally by learning it from other
chimpanzees. This kind of evidence makes it abundantly clear that
humans are not the only animals that have culture.
Yet by human standards, the culture of chimpanzees
is very limited.
They do not seem to develop it to any significant degree. I what we see
now is all they have accumulated over an indefinitely long period, then
by our standards it is not very much. Humans domesticate the horse and
invent the wheel; they put them together and have a horse and cart;
eventually they replace the horse with an internal combustion engine
and have a car. In the same vein we might imagine nutcracking
chimpanzees substituting a third stone for the nut and shaping a stone
tool; this is something hominid toolmakers did. But chimpanzees have
not done this, and in general it does not seem that one item of their
culture serves as a platform for the development of another. In sum,
chimpanzee culture is neither cumulative, no dynamic.
The climatic instability of the Pleistocene made it
a good time for
cultural agility, so also the climatic stability of the Holocene made
it a good time for cultural accumulation. It was not that Neolithic
cultures were longlasting: typically their life spans are measured in
centuries, in contrast to the millennia of Upper Palaeolithic cultures.
But the basic innovations were conserved from one culture to another,
with no need for anyone to waste time reinventing the wheel. Humans
took advantage of the Holocene ecological opportunity because of a
genetic predisposition to culture which enable them early in the
Holocene to come up with farming. This was the greatest cultural
platform since the emergence of the species.
