Alladi Ramakrishnan Hall

Darwin's "One Special Difficulty" as seen in the cellular slime moulds

Vidyanand Nanjundiah

IISc Bangalore

Among the remarkable things about ‘The Origin of Species’ is that Darwin went out of his way to present facts that appeared to be inexplicable on the basis of his theory. One of them was the presence in many species of so-called altruistic behaviour, in which an organism seems to sacrifice its own reproductive interest for that of another. The trait is seen in diverse groups and is correlated with an individual-to-group transition that has occurred repeatedly in evolution. This talk will sketch explanations for extreme forms of cooperative social behaviour, many of them traceable to Darwin himself, with special attention to the case of the cellular slime moulds or social amoebae.