My work centers on understanding evolutionary dynamics across broad spatial and temporal scales. The continuity and extent of many known evolutionary processes remains an open question in evolutionary biology, and thus investigating the spatial and temporal reach of different evolutionary mechanisms informs their relative contribution to the generation of global biodiversity. In my research, I employ novel techniques in de novo genomic assembly to gather large genomic datasets that can be used across these broad scales in non-model organisms. My dissertation work focuses on elucidating these processes in Neotropical army ants (genus: Ection), a group of keystone predators with large colonies of sterile individuals that collectively hunt, kill, and transport their prey.
One of the main results from my dissertation involves leveraging de novo genomic assembly and the unique life history traits of army ants to understand how the rise of the isthmus of Panamá impacted Neotropical biodiversity. Although it is well known that the rise of the isthmus radically changed global climate and incited the Great American Biotic Interchange by providing a corridor for organisms to migrate between North and South America, the timing and exact role of the event remain contentious. I find several cases of parallel speciation within the Neotropical army ants associated with the colonization of Central America, dating far before the full closure. Given that army ants cannot disperse across water—even by improbable “sweepstakes events”—my work corroborates recent geological evidence for land connections preceding the full closure of the isthmus. More importantly, it provides concrete geological mechanisms to explain the increased diversification in the region. In addition to suggesting an outsized role of the rise of the isthmus in generating Neotropical diversity, my work indicates that the use of these early land connections were likely widespread for organisms migrating at this time, and that the spatiotemporal complexity of the geological record needs to be considered more heavily when interpreting biogeographic patterns.
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