Zk. David-gray et al., Estimating the relatedness in a population of grey squirrels Sciurus carolinensis, using DNA fingerprinting, ACT THERIOL, 44(3), 1999, pp. 243-251
Studies on the behaviour of grey squirrels Sciurus carolinensis Gmelin, 178
8 and other species belonging to the same genus, suggest they exhibit domin
ance hierarchies among both males and females, and their mating strategy is
promiscuous or polygynous. However, there is little information available
on how dominance translates into reproductive success or on the levels of g
enetic variation or genetic substructuring within a population. To address
these questions, we used multilocus DNA fingerprinting to quantify genetic
diversity and estimate relatedness amongst individuals in a free-ranging po
pulation of grey squirrels. Background band-sharing values revealed a high
degree of genetic diversity existed. The frequency distribution of band-sha
ring values between known first order relatives and presumed unrelated anim
als was significantly different. Estimates of relatedness between individua
ls were therefore based on threshold levels of genetic similarity and used
as a tool to infer close kinship. Possible kinship groups were identified u
sing the spatial distribution of the home ranges of adults and juveniles. L
evels of relatedness between neighbouring adults was low with five family u
nits identified comprised of putative parents and their offspring. Several
juveniles from the single cohort revealed levels of relatedness intermediat
e between first order relatives and unrelated animals, suggesting possible
second order relationships leg half siblings) existed. The implications of
these relationships are discussed.