Sponsored Projects for Undergraduate Research

Capacity for dispersal influences the degree of gene flow within and between populations, and profoundly impacts the genetic diversity and structure of populations. Although the ability to disperse provides numerous ecological advantages, dispersal is energy intensive and risky, and terrestrial species may thus trade-off dispersal ability for enhanced reproductive success, especially those that colonize islands. Ants are abundant and functionally important members of nearly all terrestrial ecosystems. Despite their importance, an understanding of their capacity for dispersal is relatively understudied, given that ant dispersal is carried out by oftentimes elusive alate reproductives, which are typically produced by a colony during a limited temporal window.

Kidnapper ants (genus: Polyergus) are fascinating social parasites that rely on raiding pupae of Formica ant colonies and integrating “kidnapped” Formica workers into their colony. Kidnapper ants are widespread throughout high elevation mountainous regions in California, as well as the largest of the California Channel Islands (Santa Cruz Island).  Recent studies have shown that Polyergus in California are comprised of reciprocally monophyletic lineages that differ in the species of Formica they parasitize. Current research in the Tsutsui laboratory focuses on defining Polyergus of potential conservation concern in California, and comparing island and mainland populations of these important ant taxa. These efforts have yielded valuable collections of alate Polyergus males from across the species range, which will enable morphometric and genetic comparisons of dispersal capacity.  

This study aims to i) describe variation in flight-associated morphology across Polyergus populations and lineages, ii) test for differences in capacity of dispersal across island and mainland populations, and iii) examine the phylogeography and population genetic structure of Polyergus across their range in California.