Campus Access Only

All rights reserved. This publication is intended for use solely by faculty, students, and staff of University of the Pacific. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, now known or later developed, including but not limited to photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author or the publisher.

Date of Award

2013

Document Type

Thesis - Pacific Access Restricted

Degree Name

Master of Science (M.S.)

Department

Biological Sciences

First Advisor

Ajna Rivera

First Committee Member

Gregg D. Jongeward

Second Committee Member

Douglas C. Weiser

Abstract

The genetics of switchback evolution is largely unknown. While it is assumed that latent gene regulatory networks become reactivated to recreate an ancestral tissue, the details regarding this reactivation has yet to be elucidated. How has a network been maintained over the evolutionary history of this group? Are certain genes within these pathways more susceptible to suppression than other genes? In this study, I examined Euphilomedes carcharodonta, a member of the Sarsielloidea superfamily of ostracods, a clade which has demonstrated the loss and regain of the lateral eye multiple times over its evolutionary history. In particular, I looked at the genetic mechanisms for the development of the sexually dimorphic lateral eye, in which males have large, multifaceted image-forming eyes typical to those of other pancrustaceans (Hexapoda+Crustacea) while females do not. This sexual dimorphism is of particular interest because it allows me to study the genetic underpinnings of a regained trait using individuals of near-identical genetic backgrounds, as these organisms have a singlechromosome sex determination system (XXIXO).

Examination of developmental eye genes ec-Dachshund, ec-Daughtless, ecChaoptic, ec-Shaven, and ec-Epidermal growth factor receptor showed differential gene expression patterns in which juvenile male eyes expressed these genes at a higher level than did juvenile female eyes. These genes are thus candidate genetic components of 6 switchback evolution, as this data is a first step towards comparative transcriptomics and gene expression studies comparing multiple species.

Pages

104

To access this thesis/dissertation you must have a valid pacific.edu email address and log-in to Scholarly Commons.

Find in PacificSearch

Share

COinS

If you are the author and would like to grant permission to make your work openly accessible, please email

 

Rights Statement

Rights Statement

In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/
This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).