The evolution of culture among intelligent animals such as primates and cetaceans presently rates highly among scientists studying how innovation infiltrates a cultural activity. Individuals have been studied who pass on their behaviours to others in humans. Following several ape experiments using touch screens, the authors here decided to widen their scope beyond the apes to Papio papio, the Guinea baboon. For another paper on Australian dolphin culture, here is a very well-designed experiment. Alternatively the beautiful song cultures of German nightingales are studied here.
Nicolas Claidie`re, Kenny Smith, Simon Kirby and Joel Fagot of Aix Marseille and Edinburgh Universities publish their paper today in Proc. Roy.Soc.B, naming it, Cultural evolution of systematically structured behaviour in a non-human primate. 3 basic aspects of human evolution are exhibited in the 15 baboons finally selected from an outdoor colony (with an indoor shelter facility). The aim was specifically to compare the simple social transmission of culture with a complex lineage-specific structure in behaviour in 3 ways.
The first is a progressive increase in performance, which is typical of cultural evolution. Touching 3 or 4 squares on the computer screen was regarded as a success and was duly rewarded by the computer. This reward was a grain of dry wheat. Success then increased by 16% each time the programme was run. The mechanism of the trials was to randomly select a first baboon, whose performance was retained as a set of targets for the next subject. Eventually all 15 had been tested 6 times. This took time because all experiments were totally self-selected by the animals at their leisure. Experimental stress was thought to be reduced by never interfering with their natural curiosity.
A generation was regarded as the grids used by a baboon, having been produced by the previous baboon as generation x-1. A variation was to pass a baboon’s own previous grid to it again, termed here the within-individuals transmission procedure.
The second way to compare these baboons with humans was to investigate if systematic structures emerged in the cultures involved. All four successful squares were frequently chosen to be connected in a tetromino pattern, more so in later trials. This is simply 4 squares that touch each other on the16-square-grid Baboons may prefer this pattern and the grids could develop in this way randomly, or they may find such patterns easier to memorise. A lot of these ideas were cleared up (abandoned) when the animals performed better without tetrominos in many random trials.
This means the accumulation of many tetromino patterns in the sets causes the baboons to remember any of them better in later trials. The suggestion is of a positive feedback loop, leading to more tetrominos being produced (and less being lost) by because of the baboons’ perception.
The third method by which baboons could simulate human cultural transmission is by lineage specificity. This would lead to different kinds of structure appearing in different chains. Shape could be conveyed before colour in one chain in a sort of simple language of the tetrominos. In another chain, colour could be conveyed first. These tetrominos certainly exhibit individual cultures, languages or behaviours, even though they are only grids on touch screens.
Why are there such great differences between our cultures and all others? Indirect social transmission here is rare in nature. Social learning is normally direct from the mother while indirect learning is sometimes observed but rarely recorded as a regular behaviour. This difference alone could have led to the rapid expansion and elaboration of human cultures. Most learning like this in chimpanzees for example is limited to very narrow functional use. It could not spread easily to other behaviours. Bird song evolution could easily be compared to this baboon cultural exchange.
Errors were also interesting in this experiment. Only 37% of 1st generation grids were produced without errors, although by the end of the experiment, this rose to 72%. This suggests you don’t need to be good at these memories, but it could improve you! We don’t need to reduce our opinion of our own unique nature. We do need to consider, rats, birds whales and most primates as our equal in simple transmission of culture