Collaborative Research: Genomics of speciation and evolution of ecological traits in a geographic radiation of island kingfishers

How and why species diversify is a central question of biology and the process of speciation is how all biodiversity is created. Islands provide an excellent setting in which to study speciation in wild populations due to their discrete geography and well-characterized geologic record. The Indo-Pacific, from Southeast Asia to Polynesia, is the cradle of speciation theory and home to numerous geographic radiations of widespread, rapidly evolving species complexes.

This project will synthesize genomics and state-of-the-art trait datasets to reveal processes that promote rapid radiations in nature. Specifically, it will use a widespread, species-rich genus of island kingfishers (Aves: Todiramphus) as its study system. This project aims to make broadly applicable and generalizable predictions about the speciation process.

The outcomes of this project will be a model for future speciation research in the Pacific and serve as a springboard for pioneering new ways of studying complex phenotypes and their interactions with nature. This project will engage the public through virtual and face-to-face experiences. The researchers will create virtual collections experiences (VCEs) that highlight the associated natural history collections at the Museum of Southwestern Biology and The Field Museum.

These online tools will reveal how data are collected from specimens and used to address the project’s research objectives. The VCEs will be developed as education modules for grades 9–12, complete with lesson plans and student learning outcomes. The researchers will development a highly multisensory exhibit at The Field Museum, playing on the project’s themes of color evolution that will reach an estimated 500,000 people in Chicago.

An educational workshop will be held at the Museum of Southwestern Biology that will provide hands-on training and experience in biodiversity science to Native American and Hispanic students from UNM and New Mexico’s rural-area institutions. It will showcase professional opportunities in STEM with a focus on museum-based biodiversity science.

Speciation genomics addresses the roles of ecology, gene flow, and genomic architecture in the formation of species. This project proposes an integrative study of systematics, biogeography, plumage diversification, and ecological adaptation to test multiple hypotheses of the factors that promoted rapid diversification in a diverse and widespread radiation of island kingfishers.

Todiramphus kingfishers occur across the entire Indo-Pacific and their diversification rate rivals those of “classic” adaptive radiations. This study system provides replicated instances of sympatry and isolation, as well as divergent ecologies required for a synthetic study of diversification. The project will generate diverse datasets including whole genomes, ecological niche models, and phenotypic traits, to study how these factors facilitated rapid radiation on islands over the last 10 million years.

The proposed research will leverage this unique geographic context to provide novel insights into the multifaceted process of speciation by (a) quantifying the presence and extent of gene flow and how novel changes in genomic architecture influenced diversification; (b) assessing how extrinsic traits (plumage coloration, biogeography, and relative niche conservatism) promoted or inhibited species divergence in the clade; and (c) through a novel test of the abundance-niche-center hypothesis in the context of genomic and phenotypic diversity.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.