The evolutionary history of the rainbow ants

Monday, November 11, 2024

9:36 AM – 9:48 AM MST

Location: Phoenix Convention Center, 225 B, PCC

Presenting Author(s)

Chloe Maddison Jelley

Graduate Student
Cornell University
Ithaca, New York

Co-Author(s)

Corrie S. Moreau

Professor/Curator
Cornell University
Ithaca, New York

The ant genus Iridomyrmex, or the Rainbow Ants, is geographically limited to Australia, Southeast Asia, and a few Southern Pacific Islands and is found in a wide range of habitats. This recent radiation of ants is thought to have evolved 10-15 million years ago and is composed of 79 currently described species. There is considerable diversity in body size, colony size, defensive behavior, and nest types across the genus. Iridomyrmex is currently organized into species groups based on ecological, behavioral, and morphological similarity, but the monophyly of these groups is not certain. In order to investigate patterns of biogeography, ecological variation, behavioral diversity, morphological evolution, and diversification and their drivers across the group, evolutionary relationships must be resolved. Here we leveraged Ultraconserved Elements (UCEs) to resolve unknown evolutionary relationships for the group, mainly focusing on the validity of the already established species groups. Then, with the newly reconstructed phylogeny, we tested for patterns of diversification, historical biogeography, and morphological evolution for the genus.