Wed June 20, 2012
Dr. Andrew Colman, University of Leicester – Natural Selection and Cooperation
In today’s Academic Minute, Dr. Andrew Colman of the University of Leicester explains why natural selection seems to favor cooperation among individuals.
Andrew Colman is a professor of psychology at the University of Leicester where his research interests include game theory, cooperative reasoning, and the evolution of cooperation. Colman’s work has been published in numerous peer-reviewed journals and in 2009 he published A Dictionary of Psychology. He holds a Ph.D. from Rhodes University.
Dr. Andrew Colman – Natural Selection and Cooperation
Charles Darwin’s theory of evolution is based on a competitive process of natural selection, in which only the fittest survive. But cooperation is widespread in nature, across many species. Darwin was especially puzzled by social insects that can be exceptionally cooperative and altruistic. An even more familiar example, to most people, is alarm calling in birds. In many species of birds, when an individual spots a predator such as a cat or a hawk, it gives a loud alarm call. This warns other birds in the flock, but can only reduce the survival chances of the alarm caller itself.
So the question is: How could such behavior have evolved, and why isn’t it eliminated by natural selection? Several explanations have been suggested for special cases of various kinds. Now, Lindsay Browning, Briony Pulford, and I have discovered a mechanism that provides a new, more general explanation. Using game theory and computer simulation, we’ve discovered that natural selection promotes cooperation between similar individuals, even if they are not close relatives. This is a more general process than the “greenbeard” effect of evolutionary biology.
We call it spontaneous similarity discrimination. It happens automatically in populations in which individuals can recognize others who are similar to themselves. Our research began with populations given completely random sets of genes. Then we subjected them to random mutations and natural selection over ten thousand generations. Selective cooperation between similar individuals evolved every time.