Consciousness Blog 20 May 2012
Lydia Luncz of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, writing in Current Biology, describes how the different groups have well established methods for nut-cracking which persist over generations, even though the groups intermix, particularly through the exchange of female members, who adopt the methods of a new group and abandon the method they had previously used.
Coula nuts are hard to crack early in the season, but become softer later on; all groups use small rocks to crack the nuts early in the season (of different sizes in the varying groups, but of a constant size within a group) while some groups switch to wooden 'hammers' later in the season, which are easier to find and use than the rocks but only work with softer nuts.
"We have documented differences in hammer choice within a single forest block, with members of three different adjacent chimpanzee communities that are in regular contact with one another and are thus not genetically differentiated," says Luncz.
There are numerous messages here testifying to the usefulness of groups in evolutionary terms. The emergence of copying within a group is one of the most obvious. Copying could take place within a heterogeneous population, but is less likely to be effective without the social pressure to conform that goes along with group membership. That situation is particularly marked when an out-group female joins the group and immediately changes her technique, as the researchers observed.
The facts in this case also demonstrate the evolution of evolution as a mechanism. As between two undifferentiated populations which are in competition with each other, the most successful one will be the one which develops evolutionary mechanisms leading to more effective performance. The emergence of cognitive traits supporting 'groupedness' (whether cultural or biological) is therefore inevitable in the winning population, alongside other competitive weapons.
This leads to a suggestion that groups will develop in all life forms which have the level of cognitive abilities required to support it; in fact the two go hand in hand. Although some species are labeled 'social', this creates a false distinction: in reality all advanced species do display and utilize 'groupedness' in one form or another.
Read more in Chapter Two of Agent Human by Michael Bell, The Evolution of Social Consciousness in Animals.