Data from: Intergenerational effects of dietary changes on trait means and variance

Environmental stress can alter not only trait means but also trait
variances—an often-overlooked yet evolvable feature with ecological and
evolutionary relevance. Here, we examine how dietary stress affects both
the mean and variance of morphological and reproductive traits across two
generations in clonal Daphnia. Using a factorial design, we manipulated
maternal and offspring environments with high- (algae) or low-quality
(cyanobacteria) diets, measuring eye size, body size, and reproductive
output in eight genotypes. Morphological trait means showed consistent
treatment-by-generation interactions: low-quality diets reduced trait
size, with partial recovery upon re-exposure to high-quality food.
Reproduction was determined largely by current conditions, while eye and
body size showed legacy effects of maternal environment. Trait variance
patterns were trait-specific and not uniformly linked to mean responses:
eye size variance declined under stress, body size variance increased
across generations, and reproductive variance peaked in offspring released
from maternal stress. We also developed a conceptual framework that
specifically considered roles for condition transfer, anticipatory
plasticity, and diversified bet-hedging as potential mechanisms underlying
these intergenerational impacts on traits and variances. Although no
single mechanism explained all outcomes, our findings support condition
transfer and suggest potential co-occurrence of multiple strategies. This
data and script supports the associated article and contains all the
relevant information to replicate the study.