Data from: Fine-scale spatiotemporal patterns of genetic variation reflect budding dispersal coupled with strong natal philopatry in a cooperatively breeding mammal

The relatedness structure of animal populations is thought to be a
critically important factor underlying the evolution of mating systems and
social behaviours. While previous work has shown that population structure
is shaped by many biological processes, few studies have investigated how
these factors vary over time. Consequently, we explored the fine-scale
spatiotemporal genetic structure of an intensively studied population of
cooperatively breeding banded mongooses (Mungos mungo) over a ten-year
period. Overall population structure was strong (average Fst = 0.129) but
groups with spatially overlapping territories were not more genetically
similar to one another than non-contiguous groups. Instead, genetic
differentiation was associated with historical group-fission (budding)
events, with new groups diverging from their parent groups over time.
Within groups, relatedness was high within but not between the sexes,
although the latter increased over time since group formation due to group
founders being replaced by philopatric young. This trend was not mirrored
by a decrease in average offspring heterozygosity over time, suggesting
that close inbreeding may often be avoided, even when immigration into
established groups is virtually absent and opportunities for extra-group
matings are rare. Fine-scale spatiotemporal population structure could
have important implications in social species, where relatedness between
interacting individuals is a vital component in the evolution of patterns
of inbreeding avoidance, reproductive skew and kin-selected helping and
harming.