Does kinship affect the alarm call structure in the Yellow Ground Squirrel (Spermophilus fulvus)? [Ovlivňují příbuzenské vztahy strukturu varovných signálů sysla žlutého (Spermophilus fulvus)?]
Elena V. Volodina, Ilya A. Volodin, Vera A. Matrosova
While the closer vocal similarity between mothers and their offspring compared to other conspecifics has been reported in many mammals, e.g. whales, bats and primates, no evidence is available that vocalizations of closely related kin encode relatedness in rodents. In the yellow ground squirrel Spermophilus fulvus, females maintain matrilineal kin groups and warn kin of potential predators through alarm calls. In this study, we examine whether the keys to relatedness are presented in the structure of alarm call in this species. Using the Mahalanobis distance, we compared the similarity of structural traits in the alarm calls of 15 related (mother-daughter) and 15 unrelated (adult-juvenile) female dyads in the yellow ground squirrel. No significant differences in the Mahalanobis distance between the two groups were found. In contrast to the keys to relatedness, the keys to individuality have been reported to be strongly expressed in the yellow ground squirrel alarms. With the prevalence of the keys to individuality over the keys to relatedness, kin recognition in the matrilineal groups of this species can be based on the strong keys to individuality. As the prominent individuality of the alarm calls is sufficient to ensure the personalized relations between mothers and daughters, the keys to relatedness may be redundant and not supported by natural selection.