SAS Webinar
“A tale of two teosintes: how genetics is reshaping our understanding of maize domestication”
by
Jeffrey Ross-Ibarra
Saturday, May 11, 2024
2:00 PM – 3:30 PM PT
We are pleased to have a Jeffrey Ross-Ibarra, Evolutionary Biologist at University of California, Davis discuss his research in the evolution and adaptation of maize.
Abstract: The widely accepted narrative of maize domestication posits a single origin from the wild grass Zea mays ssp. parviglumis (lowland teosinte) in southwest Mexico, likely beginning with de novo mutation at an important gene controlling kernel architecture. However, recent genomic surveys challenge this simplicity, revealing evidence of gene flow from another wild relative, Zea mays ssp. mexicana (highland teosinte). Here we demonstrate widespread hybridization between maize and highland teosinte across time and geography, suggesting a revised model of maize origins in which maize hybridized with teosinte in the central Mexican highlands around 4000 years post-domestication. We also revisit the origin of the important domestication gene tga1, using population genetic analysis and simulations to show that relevant diversity at this key locus likely predated domestication, highlighting the importance of adaptation from pre-existing genetic variation. Together, our findings challenge existing models of maize evolution and illustrate domestication as a complex evolutionary process rather than a single event.
Jeffrey Ross-Ibarra is an evolutionary biologist who uses computational and genetic approaches to understand the evolution and adaptation of maize and its wild relatives. Dr. Ross-Ibarra’s undergraduate and early graduate background in ethnobotany has long influenced his interest in the coevolution of humans and their crop plants. More about Dr. Ross-Ibarra’s work can be found at his website rilab.ucdavis.edu.
The presentations will be presented at Young Hall, Room 224 and available via Zoom. The webinar will start at 2:00 PM PT and formally conclude at 3:30 PM. You may join starting at 1:45 PM to say “Hello” and participate in a social time.
