Publication Date

2012-05-02

Availability

Embargoed

Embargo Period

2014-05-02

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PHD)

Department

Biology (Arts and Sciences)

Date of Defense

2012-03-28

First Committee Member

Michael S. Gaines

Second Committee Member

Richard Tokarz

Third Committee Member

William Searcy

Fourth Committee Member

Carla Hurt

Fifth Committee Member

Valentin Perez-Mellado

Abstract

Selection on the same trait may differ between the sexes and among age groups as a result of sex- and age-specific strategies in reproduction and survival. Antagonistic selective pressures on traits shared between the sexes can lead to intralocus sexual conflict, which occurs when selection favors the expression of particular alleles in one sex, but disfavors the expression of those same alleles in the opposite sex. Similarly, antagonistic selection on traits shared among age groups, can lead to intralocus ontogenetic conflict, which occurs when selection favors the expression of particular alleles in one age group, but disfavors the expression of those same alleles in another agegroup. These two forms of conflict may result in individuals that deviate from their unique, sex- and age-specific optimal phenotypes. Display characters such as conspicuous coloration, may provide a prime example of this conflict because, while the reproductive benefits of expressing these traits are usually only realized by one sex (usually males) and at reproductive maturity, many of the costs of expressing these traits occur in both sexes and at all ages. In the context of intralocus sexual and ontogentic conflict, this dissertation investigates color evolution in the Ibiza wall lizard, Podarcis pityusensis, a lizard species the exhibits striking between sexes and among age-group color variation.

Keywords

Intralocus sexual conflict; ontogenetic conflict; natural selection; sexual selection; color evolution; podarcis pityusensis

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