Spatial heterogeneity in natural selection and local adaptation to ungulate herbivory in Plectritis congesta
department or school: Forestry, Faculty of
data provider: DSpace
degree campus: UBCV
creator: Skaien, Cora
issued: 2019-08-20T15:59:07Z
issued: 2019
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Understanding how organisms respond to environmental change via genetic and plastic responses can help predict species occurrence and persistence in changing landscapes. I quantified phenotypic and genotypic variation in the annual plant Plectritis congesta to test for the effects of spatial variation in ungulate herbivory on plant traits. I first surveyed 285 island and mainland populations in British Columbia, Canada, to estimate how ungulates, climate, and population isolation affect fruit phenotype and plant height. I then tested for local adaption in common gardens open to and protected from deer, and for adaptive plasticity in common gardens protected from herbivores, using populations exposed and naïve to ungulate herbivory. I then estimated genetic variance, heritability, evolvability and plasticity for plant height, shape and branch number, and assessed how these traits changed in response to intraspecific competition. Ungulate occurrence explained substantial population-level variation in phenotype, but climate and isolation had minor effects. In island populations, plants naïve to ungulate browsers were 2.6 times taller and 3.4 times more likely to produce winged fruits than plants from historically exposed populations. I observed local adaptation in common gardens open to and protected from herbivores, wherein plants from naïve populations were three times more abundant than plants from exposed populations after five years of protection from browsing. In contrast, plants from exposed populations survived three times better and were twice as fecund as plants from naïve populations when browsed, due to later bolting and flowering. Trade-offs in plant height and fecundity occurred in response to intraspecific competition: height increased 1.5 to three times as density increased but led to a ~20-30% decrease in fecundity. Moderate additive genetic variance and evolvability in traits under selection suggest a capacity for rapid evolution in 2-18 generations, …
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/71341
note: SPATIAL HETEROGENEITY IN NATURAL SELECTION AND LOCAL ADAPTATION TO UNGULATE HERBIVORY IN PLECTRITIS CONGESTA by Cora Skaien B.Sc., The University of British Columbia, 2013 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Forestry) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) August 2019 © Cora Skaien, 2019 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the dissertation entitled: Spatial Heterogeneity in Natural Selection and Local Adaptation to Ungulate Herbivory in Plectritis congesta submitted by Cora Skaien in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Forestry Examining Committee: Peter Arcese Supervisor Sally Aitken Supervisory Committee Member Judith Myers University Examiner Richard Hamelin University Examiner Additional Supervisory Committee Members: Carol Ritland Supervisory Committee Member Amy Angert Supervisory Committee Member iii Abstract Understanding how organisms respond to environmental change via genetic and plastic responses can help predict species occurrence and persistence in changing landscapes. I quantified phenotypic and genotypic variation in the annual plant Plectritis congesta to test for the effects of spatial variation in ungulate herbivory on plant traits. I first surveyed 285 island and mainland populations in British Columbia, Canada, to estimate how ungulates, climate, and population isolation affect fruit phenotype and plant height. I then tested for local adaption in common gardens open to and protected from deer, and for adaptive plasticity in common gardens protected from herbivores, using populations exposed and naïve to ungulate herbivory. I then estimated genetic variance, heritability, evolvability and plasticity for plant height, shape and branch number, and assessed how these traits chan…
has type: Thesis/Dissertation
date issued: 2019-09
is shown at: 10.14288/1.0380499
language: eng
degree discipline: Forestry
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/2429/71341