London: Baboons are capable of cumulative culture - the ability to build up knowledge over generations - thought to be limited to humans until now, a new study has found.
Humans learn from their elders and enrich this knowledge over generations. It was previously thought that this cumulative aspect of culture - whereby small changes build up, are transmitted, used and enriched by others - was limited to humans, but it has now been observed in another primate, the baboon.
The origin of cumulative culture in humans has remained a mystery to scientists, who are trying to identify the necessary conditions for this cultural accumulation.
Nicolas Claidiere and Joel Fagot, of the Laboratoire de psychologie cognitive, conducted the study at the Le Centre national de la recherche scientifique (CNRS) Primatology Center in Rousset, southeastern France.
Baboons live in groups there and have free access to an area with touch screens where they can play a "memory game" specifically designed for the study.
The screen briefly displays a grid of 16 squares, four of which are red and the others white. This image is then replaced by a similar grid, but composed of only white squares, and the baboons must touch the four squares that were previously red.
Phase one of the experiment started with a task-learning period in which the position of the four red squares was randomised. Phase two comprised a kind of visual form of "Chinese whispers" wherein information was transmitted from one individual to another.
In this second phase, a baboon's response (the squares touched on the screen) was used to generate the next grid pattern that the following baboon had to memorise and reproduce, and so on for 12 "generations."
The researchers, in collaboration with Simon Kirby and Kenny Smith from the University of Edinburgh, noted that baboons performed better in the phase involving a transmission chain (compared with random testing, which continued throughout the period of the experiment).
Due to errors by the baboons, the patterns evolved between the beginning and the end of each chain.
To the surprise of researchers, the random computer-generated patterns were gradually replaced by "tetrominos" (Tetris-like shapes composed of four adjacent squares), even though these forms represent only 6.2 per cent of possible configurations.
The baboons' performance on these rare shapes was poor during random testing, but increased throughout the transmission chain, during which the tetrominos accumulated.
Moreover, when the experiment was replicated several times, the starting patterns did not lead to the same set of tetrominos.
This study shows that, like humans, baboons have the ability to transmit and accumulate changes over "cultural generations" and that these incremental changes, which may differ depending on the chain, become structured and more efficient, researchers said.