If this behavioural trait is true, it may explain the "friend zoning" that women do in an evolutionary way. The best of friends (and the closest in genetics) rarely get laid because it would be a from of inbreeding. If organisms have a way to detect and closely associate with genetically similar individuals, it wouldn't be a stretch that mating strategies would evolve to seek individuals from outside this close group.
And then again, there's the women who like to make their rounds with entire circles of friends. I don't think any male has yet to comprehend that mating strategy.