Meeting Abstract
Parental effects may beneficially alter offspring phenotype if parental environment sufficiently predicts offspring environment. Parasitism is a common stressor across generations; thus, parental infestation could reliably predict the likelihood of infestation for offspring. Few experiments involving parasitism and maternal effects exist and none investigate this relationship across multiple generations. We investigated how maternal and grandmaternal infestation with fleas (Xenopsylla ramesis) affected offspring in a desert rodent (Meriones crassus). We used a fully-crossed design to examine litter size (LS), pup body mass at birth (PBM), and pup mass gain before weaning (PMG) for combinations of maternal and grandmaternal infestation status. No effect of treatment on LS or PBM was found. However, maternal and grandmaternal infestation status significantly affected PMG, a proxy for maturation, in male pups. These pups gained significantly more mass before weaning if maternal and grandmaternal infestation status matched, regardless of treatment. Thus, pups whose mothers and grandmothers experienced similar risk of parasitism could reach sexual maturity more quickly than those pups whose mother’s and grandmother’s infestation status did not match. These results support the contention that parents can receive external cues, such as risk of parasitism, that prompt them to alter offspring provisioning. In turn, this provisioning is beneficial if the parental environment matches that of the offspring. Thus, parasites could be a mediator of environmentally-induced maternal effects and could affect host reproductive fitness across multiple generations.
