Comparative landscape genomics reveals species-specific spatial patterns and suggests human-aided dispersal in a global hotspot for biological invasions

Abstract Biological invasions are a growing threat to native ecosystems, and genomic studies have become an increasingly useful tool for invasive species management by providing the ability to identify spatial population structure in the invaded range. In this study, we compared the spatial genetic structure of two ecologically distinct non-native lizard species both established and widespread throughout South Florida, a global hotspot for reptile invasions. We used an individual-based sampling approach to collect genetic samples of Agama picticauda , a rock specialist native to West Africa, and Basiliscus vittatus , a riparian specialist from Central and South America. We collected specimens across Miami-Dade County (the original site of introduction) and then genotyped ~ 4000 single nucleotide polymorphisms for each species. Both species exhibited fine-scale population structure at distances < 5 km for A. picticauda and < 10 km for B. vitattus, but at the county scale B. vittatus showed much stronger spatial structure compared to A. picticauda . Landscape genomic analysis revealed no significant landscape influence on A. picticauda genetic differentiation, while for B. vittatus low canopy cover was the best predictor of genetic connectivity. The genetic structure of both species may suggest human-aided dispersal is driving long distance movements, and A. picticauda appear more susceptible to these events likely due to their affinity for highly urbanized areas. By identifying variable dispersal patterns among two ecologically distinct species, we hope that this study will help combat the spread of these or similar species as they continue to arrive at urban centers across the globe.