Data from: A molecular analysis of African lion (Panthera leo) mating structure and extra-group paternity in Etosha National Park

The recent incorporation of molecular methods into analyses of social and
mating systems has provided evidence that mating patterns often differ
from those predicted by group social organization. Based on field studies
and paternity analyses at a limited number of sites, African lions are
predicted to exhibit a strict within-pride mating system. Extra-group
paternity has not been previously reported in African lions; however,
observations of extra-group associations among lions inhabiting Etosha
National Park in Namibia suggest deviation from the predicted within-pride
mating pattern. We analyzed variation in 14 microsatellite loci in a
population of 164 African lions in Etosha National Park. Genetic analysis
was coupled with demographic and observational data to examine pride
structure, relatedness, and extra-group paternity (EGP). EGP was found to
occur in 57% of prides where paternity was analyzed (n = 7) and the
overall rate of EGP in this population was 41% (n = 34). Group sex ratio
had a significant effect on the occurrence of EGP (p < 0.05),
indicating that variation in pride-level social structure may explain
intergroup variation in EGP. Prides with a lower male to female ratio were
significantly more likely to experience EGP in this population. The
results of this study challenge the current models of African lion mating
systems and provide evidence that social structure may be an important
indicator of EGP in some social mammals.