15: Evolution of turtle ants

Recent advances in phylogenomics allow for the use of large amounts of genetic information in phylogenetic inference even in diverse taxonomic groups. Ideally, the increased resolution and accuracy of such inferences facilitate an improved understanding of macroevolutionary processes. In this study, we integrate ultraconserved elements (UCEs) with fossil and biogeographic range data to explore diversification and geographic range evolution in the diverse turtle ant genus Cephalotes. In particular, we focus on the potential role of emergent land bridges (the uplift of Panama and the putative ephemeral GAARlandia land bridge linking South America and the Antilles) in shaping evolution in this group. We find that a large majority of geographic range shifts between the “South America” and “Central America” regions are temporally consistent with the development of the Panamanian land bridge, while we do not find supporting biological evidence for the GAARlandia land bridge. In contrast to previous phylogenetic studies of the turtle ants, we infer a single diversification rate regime across the genus (i.e. do not detect any rate shifts). Our findings highlight the impact of the Panamanian land bridge for Cephalotes geographic range evolution as well as the influence of taxonomic sampling on macroevolutionary inferences.