OFFSPRING ALLOCATION IN STRUCTURED POPULATIONS WITH DIMORPHIC MALES

Many fig wasp species have dimorphic males. These males often mate in different localities; one typically disperses before mating whereas th e other does not disperse. In 1979 a model was developed for offspring allocation in dimorphic fig wasps, but it assumed that females only l ay a single egg per fig. This assumption is not realistic and preclude s any effects local mate competition (LMC) may exert on morph abundanc e. I develop a model without these restrictions and show that the opti mal proportions of each morph is determined by two parameters. Firstly , the proportion of the non-dispersing morph is affected by the mean n umber of females that oviposit in a patch. This effect is due to the n egative correlation between LMC between brothers and the number of fem ales that oviposit in a patch. Secondly, the proportions of both male morphs correlate with the expected proportion of females which will ma te with each morph. The separation of the two parameters generalizes t he model to any other species which is spatially structured and which has two male morphs or even two alternative mating strategies. A compa rison of two models shows that parent-offspring conflict involving mor ph ratios will not have far reaching consequences. I test these models using the 1979 model's data and both models accurately predict the va riation in morph ratios in six species of dimorphic fig wasps.