Abstract Detail

Recent Topics Posters

Hodel, Richard [1], Massatti, Rob [2], Knowles, Lacey [3].

What processes led to hybridization between two montane sedge species?

Hybridization is prevalent when closely related species have overlapping ranges, occurring in approximately 25% of plant species.  Hybridization can arise via various processes, such as introgression of adaptive traits or phenological shifts that erode reproductive barriers, and the processes underlying hybridization can lead to different evolutionary consequences for the parental species and the hybrid.  Two sedge species, Carex nelsonii and Carex nova (Cyperaceae), which occur in the Rocky Mountains, have partially overlapping distributions and hybridize in several locations.  The two species have different habitat affinities; C. nelsonii is a high elevation specialist, and C. nova is a lower elevation wetland inhabitant.  In the overlapping portion of their ranges, there are sampling locations where both the species occur without hybridization.  However, in four locations, the parental species C. nova is found, as well as a morphologically intermediate hybrid that has habitat preferences that more closely align with C. nova, the wetland species.  Unlike many hybridizing species that exhibit a geographic cline of hybridization where two parental species overlap, these sedges hybridize primarily in geographically distant locations that do not form a centrally-located hybrid zone.  We collected genomic data (thousands of RAD-Seq loci) from 272 individuals in 22 locations and environmental data associated with each sampling locations.  We used these data to investigate and interpret the patterns of hybridization in these sedge species.  Specifically, we test the following hypotheses: 1) hybridization represents a breakdown of reproductive isolation; 2) hybridization represents interspecific gene flow of adaptive alleles.

1 - University of Michigan, Ecology and Evolutionary Biology, 1105 N University Ave, Biological Sciences 2020B, Ann Arbor, MI, 48109, United States
2 - U.S. Geological Survey, Southwest Biological Science Center, 2255 N. Gemini Dr., Flagstaff, AZ, 86001, USA
3 - University of Michigan, Ecology and Evolutionary Biology, 1105 N University Ave, Ann Arbor, MI, 48109, United States

Keywords:
hybridization
local adaptation
introgression
reproductive isolation
adaptive alleles.

Presentation Type:
Session: P, Recent Topics Posters
Location: Arizona Ballroom/Starr Pass
Date: Monday, July 29th, 2019
Time: 5:30 PM
Number: PRT033
Abstract ID:1413
Candidate for Awards:None