Maternal pathogen exposure causes diet- and pathogen-specific transgenerational costs

Transgenerational effects, whereby the environment experienced by a parent leads to an altered offspring phenotype, have now been described in a variety of taxa. In invertebrates, much of the research on these effects has concentrated on the role of parental exposure to pathogens or immune elicitors in determining offspring immune investment or disease resistance. To date, however, studies of transgenerational effects in invertebrates have generally been restricted to single infections or immune elicitors in ideal laboratory environments. Animals in field situations will commonly experience sub-optimal environments and co-infection by multiple species of parasites and pathogens, leading to increased relative costs of immune investment and changing fitness benefits from offspring responses to the parental environment. Here we investigate a more ecologically realistic scenario involving both multiple infections and resource limitation, using the Indian meal moth Plodia interpunctella as a...