The behavior stems from evolution, experts say

Jul 10, 2009 01:31 GMT  ·  By
Turn-taking may be more a question of evolution, than of education and manners, a new study finds
   Turn-taking may be more a question of evolution, than of education and manners, a new study finds

Psychologists from the University of Leicester, in the United Kingdom, have recently published a work arguing that the trait humans have of waiting their turn when standing in line, for example, may have an evolutionary basis that transcends education and good manners. They have concluded that an “invisible hand” is guiding a large number of species in this respect, after the same behavior was observed in other animals as well. The investigation was led by experts at the university's School of Psychology.

“In human groups, turn-taking is usually planned and coordinated with the help of language. For example, people living together often agree to take turns washing up the dishes after meals or taking their children to school. But turn-taking has also evolved in many other species without language or the capacity to reach negotiated agreements,” Andrew Colman, a professor in the School of Psychology and a co-author of the new research, explains.

”These include apes, monkeys, birds, and antelopes that take turns grooming each other, and mating pairs of Antarctic penguins that take turns foraging at sea while their partners incubate eggs or tend to chicks. It is far from obvious how turn-taking evolved without language or insight in animals shaped by natural selection to pursue their individual self-interests,” he adds. The other co-author of the paper has been Dr. Lindsay Browning, also a professor at the University of Leicester.

Furthermore, the researchers brought an interesting aspect to the table – they argue that the “tit for tat” type of behavior – in which a member of an animal pair, for instance, mimics the exact actions that the other member did, for a determined period of time – is not enough to explain turn-taking. However, they say, it does offer the grounds for the appearance of synchronized cooperation between members of the same species, again without the help of spoken language.

“For example, many predatory animals hunt in pairs or larger groups, and this involves synchronized cooperation. 'Tit for tat' has been shown to work very well in initiating and sustaining this type of cooperation. But where cooperation involves turn-taking, a 'tit for tat' instinct could sustain the pattern once it was established but could not initiate it in the first place. For example, in a mating pair of penguins who both went foraging or both incubated the eggs at the same time, 'tit for tat' would not be enough to evolve the habit of taking turns,” the researchers write in a new paper, to be published in the September issue of the journal Evolutionary Ecology Research.

“Turn-taking is initiated only after a species has evolved at least two genetically different types that behave differently in initial, uncoordinated interactions with others. Then as soon as a pair coordinates by chance, they instinctively begin to play 'tit for tat.' This locks them into mutually beneficial coordinated turn-taking indefinitely. Without genetic diversity, turn-taking cannot evolve in this simple way,” they add.

“In our simulations, the individuals were computer programs that were not only dumb and robotic but also purely selfish. Nevertheless, they ended up taking turns in perfect coordination. We published indirect evidence for this in 2004; we have now shown it directly and found a simple explanation for it. Our findings confirm that cooperation does not always require benevolence or deliberate planning. This form of cooperation, at least, is guided by an 'invisible hand,' as happens so often in Darwin's theory of natural selection,” Colman concludes.