Many species, including humans, can discriminate among individuals according to genetic relatedness. Yet how this kin recognition is accomplished remains largely unexplored. Spermophilus beldingi are group-living squirrels that exhibit many forms of nepotism (favoritism directed at kin), including territory defense and predator avoidance, which require the ability to identify relatives. These studies will determine how this species uses odors for recognition, examine the limits of kin discrimination, and describe the development of both kin-based odors and kin recognition. Odor production and perception will be studied with controlled odor presentations to captive S. beldingi, and these results will be complemented by observations of free-living animals. When these studies are completed, S. beldingi will be one of the first organisms for which we have a thorough understanding of favoritism based on kinship that spans both mechanistic and evolutionary explanations for kin recognition. The results can be applied to other species that are threatened with extinction, as an understanding of how individuals use space and communicate with olfactory cues may be critical to the maintenance or relocation of populations. Finally, kin-recognition research may shed light on controversies among scientists who attempt to explain human behavior in an evolutionary framework; namely, how and why humans would either advertise or conceal their relatedness to others.
