Data from: Sex-specific morphological shifts across space and time in replicate urban wall lizard introductions

As species move into new environments through founder events, their
phenotypes may diverge from native populations. Identifying the drivers
underlying such variation and the constraints on the adaptive potential of
this variation is essential for understanding how organisms respond to new
or rapidly changing habitats. Such phenotypic divergence may be especially
evident in populations introduced to new environments via human-assisted
transport or in dramatically altered environments such as cities. Sexually
dimorphic species beg the additional questions of how these new
environments may influence the sexes differently and how dimorphism may
shape the range of potential responses. The repeated translocation,
establishment, and spread of wall lizards (Podarcis spp.) from native
European populations to new locations in North America provide an
excellent natural experiment to explore how phenotypes may differ after
establishment in a new environment. Here, we quantify body shape and the
multivariate morphological phenotype (incorporating limb dimensions and
head length) of common wall lizards (P. muralis) and Italian wall lizards
(P. siculus) in replicated North American introductions. In both species,
males are larger and have larger head length and limb dimensions than
females across all sampled groups. Sexual dimorphism in the multivariate
morphological phenotype was of similar magnitude when comparing native and
introduced populations for both species, though the trajectory angles in
multivariate trait space differed in P. siculus. When comparing introduced
lizards from contemporary and historically collected museum specimens, we
identified differences of similar magnitude but in different trajectories
between sexes in P. siculus, and differences in both magnitude and
direction of sexual dimorphism in P. muralis. These idiosyncratic patterns
in phenotypic trajectories provide insight to the potential array of
processes generating phenotypic variation within species at the
intersection of invasion biology and urban evolution.