Data from: Transgenerational plasticity following a dual pathogen and stress challenge in fruit flies

Background: Phenotypic plasticity operates across generations, when the
parental environment affects phenotypic expression in the offspring.
Recent studies in invertebrates have reported transgenerational plasticity
in phenotypic responses of offspring when the mothers had been previously
exposed to either live or heat-killed pathogens. Understanding whether
this plasticity is adaptive requires a factorial design in which both
mothers and their offspring are subjected to either the pathogen challenge
or a control, in experimentally matched and mismatched combinations. Most
prior studies exploring the capacity for pathogen-mediated
transgenerational plasticity have, however, failed to adopt such a design.
Furthermore, it is currently poorly understood whether the magnitude or
direction of pathogen-mediated transgenerational responses will be
sensitive to environmental heterogeneity. Here, we explored the
transgenerational consequences of a dual pathogen and stress challenge
administered in the maternal generation in the fruit fly, Drosophila
melanogaster. Prospective mothers were assigned to a non-infectious
pathogen treatment consisting of an injection with heat-killed bacteria or
a procedural control, and a stress treatment consisting of sleep
deprivation or control. Their daughters and sons were similarly assigned
to the same pathogen treatment, prior to measurement of their reproductive
success. Results: We observed transgenerational interactions involving
pathogen treatments of mothers and their offspring, on the reproductive
success of daughters but not sons. These interactions were unaffected by
sleep deprivation. Conclusions: The direction of the transgenerational
effects was not consistent with that predicted under a scenario of
adaptive transgenerational plasticity. Instead, they were indicative of
expectations based on terminal investment.