Data from: Adult dietary protein has age- and context-dependent effects on male post-copulatory performance

The highly-conserved effect of dietary protein restriction on life-span
and ageing is observed in both sexes and across a vast range of taxa. This
extension of life-span is frequently accompanied by a reduction in female
fecundity and it has been hypothesised that individuals may reallocate
resources away from reproduction and into somatic maintenance. However,
effects of dietary protein restriction on male reproduction are less
consistent, suggesting that these effects may depend on other
environmental parameters. Using the neriid fly, Telostylinus
angusticollis, we examined age-specific effects of adult dietary protein
restriction on male post-copulatory reproductive performance (fecundity
and offspring viability). To explore the context-dependence of these
effects, we simultaneously manipulated male larval diet and adult mating
history. We found that protein-restricted males sired less viable
offspring at young ages, but offspring viability increased with paternal
age and eventually exceeded that of fully-fed males. The number of eggs
laid by females was not affected by male dietary protein, whereas egg
hatching success was subject to a complex interaction of male adult diet,
age, larval diet, and mating history. These findings suggest that effects
of protein restriction on male reproduction are highly context-dependent,
and cannot be explained by a simple reallocation of resources from
reproduction to somatic maintenance. Rather, these effects appear to
involve changes in the scheduling of male reproductive investment with
age.