The genomics of adaptation and speciation in wild sunflowers
department or school: Science, Faculty of
department or school: Botany, Department of
data provider: DSpace
degree campus: UBCV
creator: Huang, Kaichi
issued: 2021-04-21T21:43:29Z
issued: 2021
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Uncovering the genetic and evolutionary basis of adaptation and speciation is a major focus of evolutionary biology. The recent accumulation of population-scale genomic data makes it possible to identify loci underlying adaptive divergence and speciation, as well as the genomic architecture that facilitates these processes. Chromosomal inversions, a genomic rearrangement in which a segment of a chromosome is reversed end to end, have received much attention as one of the most important genomic architectures contributing to adaption and speciation. In this thesis, I used high-quality genomic data from wild sunflowers to explore the role of inversions in adaptation and speciation. I first conducted a comprehensive literature review to investigate what we have learned about the establishment and likely evolutionary role of chromosomal inversions in plants. In my second study, I made use of reduced representation sequencing data and newly developed population genomic approaches to identify seven putative chromosomal inversions that contribute to adaptive divergence of a sand dune ecotype of the prairie sunflower (Helianthus petiolaris). I further employed comparative genetic mapping to validate the inversions and identified key environmental variables significantly associated with these inversions using genome-environment association analyses. I then broadened my study to investigate the role of inversions in molecular evolution across different wild sunflowers. I showed that inversions are ideal recombination modifiers from an evolutionary standpoint because by allowing recombination among chromosomes of the same orientation but not between orientations they can facilitate adaptive divergence with gene flow, while largely averting the accumulation of deleterious mutations due to recombination suppression. Lastly, I used multiple approaches to identify loci underlying parallel ecological divergence in two dune ecotypes in H. petiolaris and found that inversions contribu…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/77885
note: THE GENOMICS OF ADAPTATION AND SPECIATION IN WILD SUNFLOWERS by Kaichi Huang B.Sc., Sun Yat-sen University, 2015 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Botany) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) April 2021 © Kaichi Huang, 2021 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the dissertation entitled: The genomics of adaptation and speciation in wild sunflowers submitted by Kaichi Huang in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Botany Examining Committee: Loren Rieseberg, Botany, UBC Supervisor Darren Irwin, Zoology, UBC Supervisory Committee Member Amy Angert, Botany, UBC Supervisory Committee Member Keith Adams, Botany, UBC University Examiner Sally Aitken, Forestry, UBC University Examiner Marc Johnson, University of Toronto Mississauga External Examiner iii Abstract Uncovering the genetic and evolutionary basis of adaptation and speciation is a major focus of evolutionary biology. The recent accumulation of population-scale genomic data makes it possible to identify loci underlying adaptive divergence and speciation, as well as the genomic architecture that facilitates these processes. Chromosomal inversions, a genomic rearrangement in which a segment of a chromosome is reversed end to end, have received much attention as one of the most important genomic architectures contributing to adaption and speciation. In this thesis, I used high-quality genomic data from wild sunflowers to explore the role of inversions in adaptation and speciation. I first conducted a comprehensive literature review to investigate what we have learned about the establishment and likely evolutionary role of chromosomal inversions in plants. In my second study, I made use of reduced representation sequencing data and newly developed…
has type: Thesis/Dissertation
date issued: 2021-05
is shown at: 10.14288/1.0396864
language: eng
degree discipline: Botany
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/77885