The Limits of Ground Squirrel Nepotism
This chapter shows that because female Belding’s ground squirrels live in about equal proximity to all categories of kin, asymmetries in their behavior toward close and distant relatives are probably not due to within-matriline differences in dispersal. Belding’s ground squirrels are diurnal, group-living rodents that inhabit the Sierra Nevada and Cascades. Female Belding’s ground squirrels were significantly more sedentary than males, and they lived in significantly greater proximity to all categories of female relatives than males. Belding’s ground squirrels give alarm calls at the approach of aerial and terrestrial predators. The chapter investigates the function of the latter call by observing 119 natural interactions between ground squirrels and predatory mammals. Some trespassers are permitted to pass through or stop on a female’s defended area without being chased. Close female relatives cooperatively chased more often and misdirected chases at each other less often than did more distant relatives.