Poor early nutrition reveals the trade-off between immune defense and mating success

Abstract EN

Although it is generally recognized that immunity is costly, not much is known about how these costs are distributed among different compartments of the immune system.

Using lines of Drosophila melanogaster that differed in their antibacterial innate immune response due to differences in the functional transcription factor Relish, we set out to investigate the condition-dependent effects of immunological maintenance on mating success.We found that when the flies were raised under poor nutritional conditions as larvae, and provided that among wild-type flies being large was costly in terms of reduced mating success, immunodeficient mutant flies that have to invest less in the maintenance of the Imd signalling pathway achieved a higher mating success compared with wild-type flies.

The results indicate a tradeoff between immunological maintenance and traits associated with male mating success, and highlight the importance of early-life environment in determining adult performance.