Data from: Transgenerational epigenetic inheritance increases trait variation but is not adaptive

Understanding organismal responses to environmental change is a central
goal of biology with profound implications for the conservation of
biodiversity. Widespread evidence of epigenetic modifications in response
to environmental stress, including those inherited across generations, has
led to considerable speculation about their role in organismal responses
to environmental change. Yet, the magnitude and fitness consequences of
epigenetic marks carried beyond maternal inheritance are largely unknown.
Here, we tested how transgenerational epigenetic inheritance (TEI) shapes
the phenotypic response of Daphnia clones to the environmental stressor
Microcystis. We split individuals from each of eight genotypes into
exposure and control treatments (P0 generation) and tracked the fitness of
their descendants to the F3 generation. We found transgenerational
epigenetic exposure to Microcystis led to reduced survival and growth
rates and no consistent effect on offspring production. TEI was associated
with increases in trait variance, suggesting the potential for heritable
bet hedging driven by TEI. Taken together, our results demonstrate that
TEI causes substantial—but not adaptive—trait shifts, suggesting
transgenerational adaptive plasticity may be rare.