Asynchronous diversification of snakes in the North American warm deserts

Aim: We quantify the degree to which co-distributed snakes across the Cochise Filter Barrier (CFB) have a shared history of population divergence and estimate the timing of divergence for each taxon pair. Location: North America. Methods: A single locus dataset was collected (n = 747 individuals) for 12 snake taxon pairs. Phylogeographical structure was estimated for each taxon. Redundancy analyses were used to assess the importance of geographical distance, climate and putative barriers to gene flow in structuring genetic diversity. Hierarchical approximate Bayesian computation was used to estimate the magnitude of synchronicity in divergence times across a well-documented phylogeographical barrier. Lastly, gene divergence and population divergence times were estimated using multiple methods. Results: There is substantial phylogeographical structure in many of the snake taxa, particularly at the CFB. A model containing distance, climate and barriers explained the greatest amount of ...