ABSTRACT

Let us talk a little more about the ‘altruism’ which often appears in the essays of the sociobiologists. Starting from the principle according to which each individual is selfishly driven by its ‘self-reproductive interest’, how can one explain altruistic behaviour? As in the case of controlled aggression sociobiologists explain this behaviour through the notion of ‘well-understood selfishness’ (WUS). The presence of WUS behaviour must obviously also be explained as resulting not from ‘choice’ but from the natural selection process. These altruistic actions appear when an individual’s ‘reproductive interest’ leads him to encourage the reproductive interest of others similar to himself. This way, he will in fact

contribute to the transmission of his own genes (in the specific proportions found in Mendelian theory). Using the WUS principle, sociobiologists explain, for instance, why some species produce sterile individuals (hymenoptera, white ants). This phenomenon occurs because, with hymenoptera, females are ‘diploids’, that is to say they have a father and a mother whereas males are ‘haploids’ (only have a mother). Two females coming from the fertilization of the queen by the same male are genetically closer to each other than they would be to their own daughter. Quite so, since two females who have the same father have 50 per cent of the same genes, because the father, a haploid, transmits exactly the same genes to his daughters, to which one adds 25 per cent of the same genes from the diploid mother. On the other hand, mother and daughter will share only 50 per cent of the same genes. Hence the ‘reproductive interest’ that some females have in not reproducing and helping other females to reproduce instead. This hypothesis allows us to understand why, for instance, there are no male ‘workers’ within hymenoptera. Indeed, a male is no closer to his siblings than to his female offspring (he cannot have sons). These examples illustrate the part played by ‘parental selection’ in the observation of the phenomenon of altruism. In other cases, sociobiologists explain altruism by the development of mechanisms of ‘parental manipulation’, understood as the result not of a deliberate choice but of a re-affirmation by the process of natural selection. These mechanisms make the parents force one of their children to serve the other. In other cases still, sociobiologists explain altruism by the principle of reciprocity.