Graduation Date
Summer 2018
Document Type
Thesis
Program
Master of Science degree with a major in Natural Resources, option Wildlife
Committee Chair Name
Dr. Jared Wolfe
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Dr. Kristin Brzeski
Second Committee Member Affiliation
Community Member or Outside Professional
Third Committee Member Name
Dr. Luke Powell
Third Committee Member Affiliation
Community Member or Outside Professional
Fourth Committee Member Name
Dr. Daniel Barton
Fourth Committee Member Affiliation
HSU Faculty or Staff
Fifth Committee Member Name
Matthew Johnson
Fifth Committee Member Affiliation
HSU Faculty or Staff
Subject Categories
Wildlife
Abstract
Environmentally-induced stress can initiate a molecular response through DNA methylation, which can alter gene expression, thereby serving as a mechanism allowing individuals to acclimate to a changing environment within their lifetime. In addition to DNA methylation, the production and release of corticosterone is a physiological mechanism by which birds can cope with acute environmental stressors. To assess how environmental stress impacted DNA methylation and corticosterone, I collected blood and feather samples from three understory avian species (Alethe castanea, Bleda notatus and Pseudalethe poliocephala), along a disturbance gradient in the lowland Guinean rainforest adjacent to the village of Oyala, Equatorial Guinea. I used two binomial mixed-effect models for each species to identify gene loci that were differentially methylated with respect to the amount of corticosterone deposited in a tail feather and distance to forest edge when captured. I identified 195, 126 and 246 sites differentially methylated by feather CORT and 296, 166 and 254 sites differentially methylated by distance to forest edge for Alethe castanea, Bleda notatus and Pseudalethe poliocephala, respectively. I also found a significant negative relationship between feather CORT and overall feather brightness indicating there may be trade-offs between coping with environmental stressors and fitness. I found substantial variation in CORT and DNA methylation along the disturbance gradient, suggesting that environmentally-induced molecular and endocrinological responses are prevalent in degraded tropical forests.
Citation Style
Journal of Wildlife Management
Recommended Citation
Wiegardt, Andrew K., "The effects of forest degradation on DNA methylation in Central African songbirds" (2018). Cal Poly Humboldt theses and projects. 186.
https://digitalcommons.humboldt.edu/etd/186
Included in
Molecular Genetics Commons, Ornithology Commons, Other Ecology and Evolutionary Biology Commons