Frequent mating is possible because, in contrast to males of all other social Hymenoptera, the testes of ergatoid Cardiocondyla males persist throughout their whole lives, resulting in a permanently replenishable sperm supply [ 9, 10].
If the populations are viable, i.e., if they have a vegetative growth rate higher than 0, then less frequent mating (dormancy) is beneficial in terms of the average fitness of the pan-sexual population.
To further test the level of linkage disequilibrium in the subpopulations, the index of association was measured (ISA; Table 2) and the largest subpopulation (X) shown to be in LE, thus indicating frequent mating within this population.
At high latitudes, increased activity time has, however, been predicted [ 27] and shown to be associated with more frequent mating and thus greater offspring viability and survival in warmer years [ 12, 13].
There is no hybrid sterility between H. cydno and H. heurippa, and insectary mate choice experiments produce frequent matings in one direction (between H. heurippa males and H. cydno females).
One of these subpopulations is in linkage equilibrium thus supporting the occurrence of frequent mating.
This study suggests that the combination of limited dispersal and frequent mating between sibs leads to a very high level of inbreeding in X. germanus.
One of these subpopulations (X) shows linkage equilibrium and therefore evidence for frequent mating.
Frequent mating of females may therefore contribute to the maintenance of high sperm quality.
Frequent mating of females may therefore contribute to the maintenance of high sperm quality, as males remove sperm stored in the female before transferring their own sperm, although removal is not always complete.
