Data from: Characterizing morphological (co)variation using structural equation models: body size, allometric relationships and evolvability in a house sparrow metapopulation

Body size plays a key role in the ecology and evolution of all organisms.
Therefore, quantifying the sources of morphological (co)variation,
dependent and independent of body size, is of key importance when trying
to understand and predict responses to selection. We combine structural
equation modeling with quantitative genetics analyses to study
morphological (co)variation in a meta-population of house sparrows (Passer
domesticus). As expected, we found evidence of a latent variable ‘body
size’, causing genetic and environmental covariation between morphological
traits. Estimates of conditional evolvability show that allometric
relationships constrain the independent evolution of house sparrow
morphology. We also found spatial differences in general body size and its
allometric relationships. On islands where birds are more dispersive and
mobile, individuals were smaller and had proportionally longer wings for
their body size. While in islands where sparrows are more sedentary and
nest in dense colonies, individuals were larger and had proportionally
longer tarsi for their body size. We corroborated these results using
simulations and show that our analyses produce unbiased allometric slope
estimates. This study highlights that in the short term allometric
relationships may constrain phenotypic evolution, but that in the long
term selection pressures can also shape allometric relationships.