What is the role of genes in kin recognition?
Answer 1Hard to answer as this is not settled in evolutionary biology. Some call this the " green beard effect, " where one organism's kin recognizes the organism by some physiological marker that is reflective of the genetic relatedness. Still, the evidence for this concept is rather thin, so we do not know if we are seeing such an effect, or one is just seeing the result of organisms being raised in close proximity.Answer 2There are various ways for genes to affect the recognition of kin. For instance, genes may affect pheromone production, giving the family member a recognizable scent. Genes might affect fur patterning, or bird-song. Certainly humans are often able to distinguish relatives by their facial features, even if they had not met these relatives before.Note that there is much still to be learned about the role of such genes in kin altruism, and that the mechanisms of kin altruism may not even need to rely on such outward markers. The subjects of kin recognition and kin altruism should, to some extent, be studied individually.