Data from: The quantitative genetics of physiological and morphological traits in an invasive terrestrial snail: additive versus non-additive genetic variation

1. The distribution of additive versus non-additive genetic variation in
natural populations represents a central topic of research in
evolutionary/organismal biology. For evolutionary physiologists,
functional or whole-animal performance traits (“physiological traits”) are
frequently studied assuming they are heritable and variable in
populations. 2. Physiological traits of evolutionary relevance are those
functional capacities measured at the whole-organism level, with a
potential impact on fitness. They can be classified as capacities (or
performances) or costs, the former being directly correlated with fitness,
and the latter being inversely correlated with fitness (usually assumed as
constraints). 3. In spite of their obvious adaptive significance, the
additive genetic variation of physiological traits, and its relative
contribution to phenotypic variance (or narrow-sense heritability) in
comparison to maternal, dominance or epistatic variance, is known only for
a few groups such as insects and mammals. 4. In this study, we assessed
the additive and maternal/non-additive genetic variation in a suite of
physiological and morphological traits in populations of the land snail
Cornu aspersum. 5.Except for dehydration rate (h2= 0.32 ± 0.15), egg mass
(h2= 0.82 ± 0.30) and hatchling mass (h2= 1.01 ± 0.31) (population = fixed
effect), we found very low additive genetic variation. Large
non-additive/maternal effects were found in all traits. Cage effects did
not change the results, indicating low contribution of common
environmental variance to our results. No differences were found between
the phenotypic or non-additive genetic variance/covariance matrices. 6.
Even though we compared populations across 1300 km in a common garden
setup, our results suggest an absence of physiological as well as
morphological differentiation in these populations. 7. These results
contrast with previous analyses in the original distributional range of
this species, which found high additive genetic variation in morphological
traits. These are intriguing results demanding further quantitative
genetic studies in the original distributional range of this species as
well as the history of colonization of this invasive species.