Like humans, some fish, birds, or insects sometimes raise offspring that are not their own. Helping individuals who are not genetically related to us does not seem logical. Scientists from the University of Bern have been interested in this mechanism of altruism.
To be altruistic is to do something that benefits someone else, at a cost to oneself. Taking care of his descendants or his younger brothers and sisters is part of it. From an evolutionary point of view, it is about saving one’s own genes in the next generation. So why would a fish in Lake Tanganyika, Africa, take care of a baby that isn’t its own?
The Institute of Ecology at the University of Bern has developed a model to simulate its decision. A model applicable to fish, mammals and birds. The conclusion of his, explains that by taking care of other people’s children, a group of animals becomes larger. The risk against predators is diluted and there is a greater chance of producing own offspring.
Help genetically close descendants
However, if the environmental conditions become more favorable with fewer predators, for example, one becomes more selfish. “In this case, there is greater competition to be independent in reproduction. The helpers favor offspring that are genetically close to them until they can, themselves, reproduce. So there are two different selection pressures depending on the environment”, explains Irene Garcia Ruiz of the University of Bern, Thursday in La Matinale.
So can we really speak of altruistic behavior? “The real question is what is the selfish benefit of these semi-altruistic acts?” asks Irene Garcia Ruiz. “A hypothesis of the evolution of cooperation in our species is probably friendship. I help you today, but tomorrow you help me.” A behavior inherited by natural selection.