Maternal age affects offspring lifespan of the seed beetle, Callosobruchus maculatus

1. Offspring from older parents often have shorter adult lifespans than offspring of younger mothers. We examine the effects of offspring genotype, maternal age and paternal age on offspring survival, development and adult lifespan in the seed beetle, Callosobruchus maculatus . 2. Females took about a quarter of a day longer to develop from an egg to an adult and lived ≈ 7 days longer than males. Mortality patterns were best described by a logistic mortality model, and all three model parameters differed significantly between the sexes; females had a higher baseline mortality rate than males but the mortality rate increased more slowly in females than in males. Females also showed a delay, relative to males, in the age at which mortality became age-dependent. 3. The proportion of eggs that hatched and larval survivorship both declined with increasing maternal age, while egg-to-adult development time increased substantially. Contrary to the pattern observed in many other organisms, offspring of older mothers lived longer than offspring of younger mothers, even after controlling for heterogeneity among families. There was no evidence that paternal age affected any offspring traits. 4. The effect of maternal age on offspring lifespan was greater for male offspring than for female offspring (consistent with the general observation that the genetic and environmental factors affecting lifespan differ between the two sexes) and varied among sire families (indicating that offspring genotype mediated the non-genetic effect of maternal age on lifespan).