Pea aphid winged and wingless males exhibit reproductive, gene expression, and lipid metabolism differences

Alternative, intraspecific phenotypes offer an opportunity to identify the mechanistic basis of differences associated with distinctive life-history strategies. Wing dimorphic insects, in which both flight-capable and flight-incapable individuals occur in the same population, are particularly well-studied in terms of why and how the morphs trade-off flight for reproduction. Yet despite a wealth of studies examining the differences between female morphs, little is known about male differences, which could arise from different causes than those acting on females. Here we examined reproductive, gene expression, and biochemical differences between pea aphid (Acyrthosiphon pisum) winged and wingless males. We find that winged males are competitively superior in one-on-one mating circumstances, but wingless males reach reproductive maturity faster and have larger testes. We suggest that males tradeoff increased local matings with concurrent possible inbreeding for outbreeding and increased ab...