Data from: The genetic variance but not the genetic covariance of life-history traits changes towards the north in a time-constrained insect

Seasonal time constraints are usually stronger at higher than lower
latitudes and can exert strong selection on life history traits and the
correlations among these traits. To predict the response of life history
traits to environmental change along a latitudinal gradient, information
must be obtained about genetic variance in traits and also genetic
correlation between traits, i.e., the genetic variance-covariance matrix,
G. Here, we estimated G for key life history traits in an obligate
univoltine damselfly that faces seasonal time constraints. We exposed
populations to simulated native temperatures and photoperiods and common
garden environmental conditions in a laboratory setup. Despite differences
in genetic variance in these traits between populations (lower variance at
northern latitudes), there was no evidence for latitude-specific
covariance of the life history traits. At simulated native conditions, all
populations showed strong genetic and phenotypic correlations between
traits that shaped growth and development. The variance-covariance matrix
changed considerably when populations were exposed to common garden
conditions compared with the simulated natural conditions, showing the
importance of environmentally induced changes in multivariate genetic
structure. Our results highlight the importance of estimating
variance-covariance matrixes in environments that mimic selection
pressures and not only trait variances or mean trait values in common
garden conditions for understanding the trait evolution across populations
and environments.