Variation in male post-copulatory investment: ontogeny to progeny Macartney, Erin en_US 2022-03-23T11:54:13Z 2022-03-23T11:54:13Z 2019 en_US
dc.description.abstract Condition-dependence theory has been widely applied to exaggerated male signaling traits, and more recently to certain sperm and semen traits. However, such post-copulatory traits can be highly cryptic and multi-faceted, and the published literature shows considerable variation in trait expression due to male condition. This thesis aims to uncover sources of variation in post-copulatory trait expression, and to incorporate male investment in ejaculate and offspring quality into a condition-dependence life-history framework. Using meta-analyses and meta-regression in Chapter Two, I demonstrate that much of the variation in post-copulatory responses to nutrient limitation (used as a manipulation of condition) is accounted for by differences in the type of nutrients, the ontogenetic life-stage when nutrients are limited, and the type of trait. Trait responses are also taxon-specific. In Chapter Three, I empirically demonstrate that developmental nutrient limitation strongly reduces testes and accessory gland size, as well as sperm movement within the female reproductive tract, and that adult diet does not alter such responses in the neriid fly, Telostylinus angusticollis. In Chapters Four and Five, I consider condition-dependent effects on offspring quality. In Chapter Four, I argue that non-genetic paternal effects conferred through epigenetic factors may also be costly, condition-dependent traits. In Chapter Five, I use T. angusticollis to test if frequent mating results in a condition-dependent reduction in fecundity and offspring quality. Surprisingly, frequent mating did not result in reduced fecundity or offspring quality, but did result in a reduced mating rate. Finally, in Chapter Six, I demonstrate that male Drosophila melanogaster suffer sperm depletion across successive matings, but the rate of depletion is not dependent on diet or genotype. Instead, males vary in ability to mate multiply, and individuals that mate more also transfer more sperm. Thus, variation in male post-copulatory performance depends substantially on unknown factors that are unrelated to nutrition and genotype. Overall, this thesis demonstrates that sperm and semen traits are affected by many different factors, and that variation in such traits can be highly complicated. Understanding differences in post-copulatory trait expression will provide increased understanding into the evolution of mating systems and reproductive investment. en_US
dc.language English
dc.language.iso EN en_US
dc.publisher UNSW, Sydney en_US
dc.rights CC BY-NC-ND 3.0 en_US
dc.rights.uri en_US
dc.subject.other Plasticity en_US
dc.subject.other Evolution en_US
dc.subject.other Reproduction en_US
dc.title Variation in male post-copulatory investment: ontogeny to progeny en_US
dc.type Thesis en_US
dcterms.accessRights open access
dcterms.rightsHolder Macartney, Erin
dspace.entity.type Publication en_US
unsw.relation.faculty Science
unsw.relation.originalPublicationAffiliation Macartney, Erin, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW en_US School of Biological, Earth & Environmental Sciences *
unsw.thesis.degreetype PhD Doctorate en_US
Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
public version.pdf
8.74 MB
Resource type