Sex-specific Morphological Shifts Across Space and Time in Replicate Urban Wall Lizard Introductions

Area of Science:

• Evolutionary Biology
• Invasion Biology
• Urban Ecology

Background:

• Phenotypic divergence occurs when species colonize new environments.
• Understanding adaptive potential is crucial for species in changing habitats.
• Sexually dimorphic species present unique challenges in novel environments.

Purpose of the Study:

• To investigate phenotypic divergence in introduced wall lizard populations in North America.
• To examine how sexual dimorphism influences adaptation in new environments.
• To compare contemporary and historical museum specimens for evolutionary insights.

Main Methods:

• Quantified body shape and multivariate morphology of common wall lizards (P. muralis) and Italian wall lizards (P. siculus).
• Analyzed morphological data from native and introduced populations across North America.
• Compared contemporary introduced populations with historical museum specimens.

Main Results:

• Males were larger with greater head length and limb dimensions than females in both species.
• Sexual dimorphism magnitude was similar between native and introduced populations, but trajectory angles differed in P. siculus.
• Introduced P. siculus showed sex-specific phenotypic changes over time, while P. muralis exhibited changes in both magnitude and direction of sexual dimorphism.

Conclusions:

• Introduced wall lizards exhibit species- and sex-specific phenotypic trajectories.
• Environmental factors in new habitats influence the evolution of sexual dimorphism.
• These findings contribute to understanding invasion biology and urban evolution.