Inbreeding adversely affects fitness, whereas heterozygosity often
augments it. Therefore, mechanisms to avoid inbreeding and increase
genetic distance between mates should be advantageous in species where
adult relatives reside together. Here we investigate mate choice for
genetic dissimilarity in chimpanzees, a species in which many females
avoid inbreeding through dispersal, but where promiscuous mating and
sexual coercion can limit choice when related adults reside together. We
take advantage of incomplete female dispersal in Gombe National Park,
Tanzania to compare mate choice for genetic dissimilarity among immigrant
and natal females in two communities using pairwise relatedness measures
in 135 genotyped chimpanzees. As expected, natal females were more related
to adult males in their community than were immigrant females. However,
among 62 breeding events, natal females were not more related to the sires
of their offspring than immigrant females, despite four instances of close
inbreeding. Moreover, females were generally less related to the sires of
their offspring than to non-sires. These results demonstrate that
chimpanzees may be capable of detecting relatedness and selecting mates on
the basis of genetic distance. Pairwise Relatedness
DataThis excel file has
three sheets containing pairwise relatedness data used in each of the
three main analyses in the paper. 1) Relatedness between male-female
dyads. 2) Relatedness between mothers and sires. 3) Relatedness in
breeding and non-breeding dyads. A final sheet explains the column
headings.Walker_etal_data.xlsxChimpanzee GenotypesThis file includes genotyping data at 11 microsatellite loci used for paternity analyses. All genotyped individuals are included and are assigned the same code given in the pairwise relatedness file.Walker_etal_genotypes.xlsx