The evolution of gained traits in fishes
Abstract/Contents
- Abstract
- Evolution has generated a fascinating diversity of life on earth that has captured the imagination of scientists for centuries. To understand how this diversity arose, evolutionary biologists have tried to link adaptive phenotypes seen in nature to the causal DNA sequence changes. Identifying the mutations for many different traits in many different species across different ranges of evolutionary time allows us to determine the genetic mechanisms that are used and elucidate whether evolution is repeatable. To study the genetic mechanisms underlying adaptive traits, I have focused on two groups of fish, stickleback and sea robins, because of their unique ecology and intriguing and diverse skeletal traits. To study the genetics of the gain and loss of traits in a given species, the ability to edit their genome is a powerful tool to link genotype to phenotype. In chapter 2 of my thesis, I describe the work I did to establish CRISPR-Cas9 genome editing in stickleback fish and its use to characterize the functions of genes previously implicated in major evolutionary changes in sticklebacks. In chapter 3, these methods were applied to help understand the role of a pelvic enhancer (PelA) in stickleback evolution. While the genetic basis of trait loss has been well characterized in many examples, the genetic mechanisms by which traits are gained are not as well understood. In chapter 4, I studied the gain of spines in two different stickleback genera (Gasterosteus and Apeltes) and characterized the genetic mechanisms. In doing so, I uncovered the role of a Hox cluster. Through independent cis-regulatory mutations in the same enhancer, the expression patterns of the genes have been modified affecting both the length and number of spines. These findings provide evidence to support the long-standing hypotheses and debates surrounding the role of Hox genes in trait evolution in wild populations. In addition to developing genetic tools, the ability to hybridize species remains a powerful way to characterize the differences between species. In chapter 5, I studied the possibility of hybridizing many different sticklebacks to determine if they are viable and if they can be used to study intraspecies differences. Finally, to explore more dramatic examples of the gain of new traits, I worked on developing sea robins as a new system in which to study the gains of "legs" (modified pectoral fin rays) and new spinal lobes controlling them. The study of evolution across broader taxonomic distances and in new and diverse species can help shed more light on questions relating to the genetic basis of evolution and how repeatable it is.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2022; ©2022 |
| Publication date | 2022; 2022 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Wucherpfennig, Julia Isabelle |
|---|---|
| Degree supervisor | Kingsley, David M. (David Mark) |
| Thesis advisor | Kingsley, David M. (David Mark) |
| Thesis advisor | Fuller, Margaret T, 1951- |
| Thesis advisor | Nusse, Roel, 1950- |
| Thesis advisor | Talbot, William S |
| Degree committee member | Fuller, Margaret T, 1951- |
| Degree committee member | Nusse, Roel, 1950- |
| Degree committee member | Talbot, William S |
| Associated with | Stanford University, Department of Developmental Biology |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Julia Isabelle Wucherpfennig. |
|---|---|
| Note | Submitted to the Department of Developmental Biology. |
| Thesis | Thesis Ph.D. Stanford University 2022. |
| Location | https://purl.stanford.edu/fz516st8941 |
Access conditions
- Copyright
- © 2022 by Julia Isabelle Wucherpfennig
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
Also listed in
Loading usage metrics...