Abstract Detail



Hybrids and Hybridization

Baniaga, Anthony [1], Barker, Michael [2].

Hybridization, polyploidy, and adaptation to extreme environments by Selaginella.

Hybridization and polyploidization (whole genome duplication) are common and important evolutionary processes in vascular plants. Despite the frequency of these processes most nascent polyploid species go extinct due to a combination of genetic and ecological obstacles, and little is known about the relative role of hybridization and whole genome duplication to allopolyploid establishment. Selaginella have some of the smallest nuclear genomes found in vascular plants as well as variable levels of desiccation tolerance, with many around the world known as resurrection plants. The southwestern U.S. and mainland mexico is a center of functional and taxonomic diversity for the genus. In the transition zone between the Lower Colorado River Valley and Arizona Upland subdivisions in the Sonoran Desert diploid hybrids and allopolyploids are found, formed between crosses of Selaginella arizonica and S. eremophila [Selaginellaceae]. Both hybrid populations occupy drier, warmer climatic niches than either of their parents and have different ecophysiological strategies associated with more variable precipitation. Using a combination of transcriptome, genome, and ddRADseq data we confirm the parentage and hybrid nature of these populations. We also infer the relative contributions of each parent and their distribution in both hybrid genomes. Our results have broad implications for our understanding of the ecological and evolutionary genetic processes that occur in nascent diploid and polyploid hybrid populations in natural conditions.


1 - University Of Arizona, Ecology & Evolutionary Biology, 1041 Lowell, Bsw, Po Box 210088, Tucson, AZ, 85721, United States
2 - Department Of Ecology & Evolutionary Biology, P.O. Box 210088, Tucson, AZ, 85721, United States

Keywords:
Hybridization
Polyploidy
Niche Evolution
Selaginella.

Presentation Type: Oral Paper
Number: 0004
Abstract ID:422
Candidate for Awards:Margaret Menzel Award


Copyright © 2000-2018, Botanical Society of America. All rights reserved