Is mate choice based on relatedness or heterozygosity?
We found no evidence for relatedness- or heterozygosity-based
assortative mating. There was no difference between relatedness of real
mating pairs and randomly generated mating pairs (n = 10 pairs, breeding
pool of 12 females and 12 males, p = 0.565). Likewise, homozygosity by
loci (HL) was not significantly correlated between pair mates (r =
-0.527, n = 10 pairs, p = 0.118).
Despite the lack of evidence for active inbreeding avoidance during mate
choice, relatedness (Wang’s r ) between mating partners was
generally low, averaging -0.033 (for comparison, mean r for
simulated unrelated individuals was 0.012), and none of the pair mates
shared the same mtDNA haplotype (Supplementary Table 1, Fig. 1). Only in
one pair were the partners found to be second-degree kin (Group 6,r = 0.285). The mtDNA haplotype network (Fig. 2) showed no clear
pattern of haplotype similarity between pair mates: some had closely
related haplotypes (e.g., Groups 4, 5, 9), while others had only
distantly related haplotypes (e.g., Groups 1, 11).