Abstract Detail

Molecular Ecology and Evolution

Layman, Nathan [1], Busch, Jeremiah [1].

Inbreeding Depression and the Spread of Selfing in Polyploids.

Two of the most common trends in angiosperm evolution are 1) the loss of self-incompatibility (SI) and 2) whole genome duplication or polyploidization. Early work suggested that these two processes are associated. Historically there have been two major schools of thought to explain the association between selfing and polyploidy, yet the interaction between these frameworks is not clear. First, inbreeding depression has long been advanced as a major force resisting the transition to selfing and whole genome duplication is thought to erode this barrier. Secondly, polyploid populations may be more likely to escape extinction if they are capable of selfing. Individual based modeling provides a unique opportunity to test the predictions of these pathways, which differ both in the timing and level of selective pressure. We used this approach to test the hypothesis that inbreeding depression dynamically declines during the formation of polyploids. In a separate simulation, we also tracked the frequency of mutations permitting selfing in polyploid populations that experienced variable levels of initial inbreeding depression. This work directly tests the hypothesis that declines in inbreeding depression in polyploids provide more permissive conditions for the evolution of selfing. Further, outlining these dynamics sets the groundwork for further investigation into the relationship between the two evolutionary pathways.

1 - Washington State University, SBS, PO Box 644236, Pullman, WA, 99164, USA

Keywords:
Polyploidy
Inbreeding Depression
simulation modeling
Self Incompatibility
plant mating systems
selfing.

Presentation Type: Oral Paper:Papers for Topics
Session: 61
Location: Salon 15/16/The Shaw Conference Centre
Date: Wednesday, July 29th, 2015
Time: 11:45 AM
Number: 61015
Abstract ID:1072
Candidate for Awards:Margaret Menzel Award