Cityscape genetics: structural vs. functional connectivity of an urban lizard population

Area of Science:

• Ecology
• Genetics
• Urban Ecology

Background:

• Functional connectivity is vital for population persistence, but often overlooked in favor of structural connectivity.
• Urban landscapes present unique challenges to animal movement due to anthropogenic barriers.
• Assessing connectivity in dynamic cityscapes requires integrated approaches.

Purpose of the Study:

• To assess and compare structural and functional connectivity for an urban lizard species.
• To combine species distribution models (SDMs) with landscape genetic optimization.
• To identify key environmental and anthropogenic factors influencing gene flow in urban habitats.

Main Methods:

• Species distribution models (SDMs) were developed using environmental factors.
• An individual-based landscape genetic optimization procedure was applied to SDMs.
• Presence-only and presence-absence modeling approaches were compared.

Main Results:

• Structural connectivity was influenced by structural diversity and substrate type.
• Functional connectivity (gene flow) was primarily modeled by water cover (rivers as barriers).
• Buildings were the only significant anthropogenic barrier identified; SDM factor importance can be misleading.

Conclusions:

• Optimizing SDMs with landscape genetics provides a robust framework for modeling gene flow in urban environments.
• Rivers act as significant barriers to gene flow in urban lizard populations.
• This approach can inform management strategies for native and non-native populations in cities.