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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Transcriptomic basis of post-mating responses in females of the parasitic wasp Nasonia vitripennis

Watt, Rebekah January 2012 (has links)
Mating in insects influences suites of behavioural and physiological changes in females. These changes can include key female traits such as dispersal, foraging, oviposition and female remating or receptivity. Whilst much is known at the phenotypic level about post-mating changes in reproductive biology across many species, much less is known at the genetic level, especially outside of established model organisms such as Drosophila melanogaster. In the parasitic wasp Nasonia vitripennis courtship behaviour, rather than copulation, is believed to be primarily responsible for driving changes in female post-mating behaviour. Here we have studied female receptivity and post-mating gene expression changes associated with courtship and copulation in Nasonia vitripennis. Firstly we considered the influence of the duration of various elements of courtship and mating on female re-mating rates. We were able to identify an association between long pre-copulatory courtship durations and females which are less likely to re-mate (after 24 hours) and suggest that this may be driven by females which are generally less receptive. We also observed that males may be capable of determining female mating state, taking longer to engage in courtship with mated females than virgin females. To further explore the influence of mating on female post-mating behavioural and physiological processes, we explored changes in gene expression occurring in response to mating. To do this we utilised two different transcriptomic sequencing approaches developed for the Illumina next-generation sequencing platform. Using a tag-seq approach we considered the differential gene expression occurring in response to mating in head and body (comprising of the thorax and abdomen) tissues across two time-points (30 minutes and four hours). We were able to identify large changes in expression in head tissues across time-points in comparison to more subtle changes in body tissues. We suggest that head tissues may be more closely associated with post-mating changes in behaviour, whilst body tissues are perhaps physiologically more associated with egg production and influenced less by mating per se. Finally, using an RNA-seq approach, we considered the gene expression changes occurring in female body tissues in response to three elements of male courtship across two time-points (30 minutes and 24 hours). We hoped to narrow down the role of male courtship and/or insemination in post-mating gene expression differences, addressing first the more limited changed in body tissues. We showed that time-point was the most important factor associated with post-mating gene expression, with the courtship components tested being associated with very little expressional change. The data presented in this thesis suggests that male courtship may not be that important for driving the post-mating behavioural and genetic changes seen in Nasonia, perhaps limiting the scope for sexual conflict over reproduction in this species.
2

Sexual attraction to exploitability

Goetz, Cari Debora 23 June 2014 (has links)
This research explores the relationship between sexual exploitability and sexual attractiveness. Sexual exploitability describes the ease with which a woman could be pressured, deceived, or coerced into sex, or sexually assaulted. Study 1 documented novel cues to sexual exploitability. Moreover, men found women displaying these cues to be attractive as short-term mates, supporting the hypothesis that men’s attraction functions to motivate the pursuit of sexually accessible women. In Study 2, it was determined that women also perceived other women who displayed cues to exploitability as sexually attractive to men. Because displaying exploitability enhances a woman’s sexual attractiveness, women may have co-evolved mate attraction mechanisms designed to capitalize on this feature of male sexual psychology. In Study 3, it was hypothesized that three individual differences would predict which women would be more likely to signal exploitability as a mate attraction tactic: propensity towards short-term mating, relationship status, and self-perceived mate value. Women self-reported their likelihood of using mate attraction tactics involving the intentional display of exploitability cues. Women inclined toward casual sex were more likely to report using such tactics. In Study 4, a separate set of female participants made a hypothetical video dating profile to provide a record of their actual behavior in a mate attraction scenario. Women inclined toward short-term mating and high in the personality characteristic of Openness to Experience were more likely than their female counterparts to display exploitability cues in their videos. These convergent results across studies support the hypothesis that women pursuing short-term mating capitalize on the relationship between exploitability and attractiveness to achieve their mating goals. Results from these studies expand our knowledge of sexual exploitability and mate attraction. Documentation of a comprehensive list of cues to exploitability expands our knowledge of potential predictors of sexual victimization. Identification of individual differences that predict which women may functionally display exploitability cues increases our understanding of which women may be at greater risk for sexual exploitation. / text
3

Behavioural aspects of the population genetics of the domestic cat

Horsfield, Giles Frederick January 1998 (has links)
No description available.
4

Sexual selection and sperm competition in Soay sheep

Preston, Brian T. January 2001 (has links)
No description available.
5

An investigation into the polygynous mating system of the wren Troglodytes troglodytes indigenus (L.)

Sweeney, John James January 1998 (has links)
No description available.
6

The social organisation and mating systems of the red bellied tamarin (Saguinus labiatus labiatus) : Behavioural observations in captivity and in the wild

Buchanan-Smith, H. M. January 1989 (has links)
No description available.
7

Sexual selection and sexual conflict in the seaweed fly, Coelopa frigida

Shuker, David Michael January 1998 (has links)
No description available.
8

The role of extra-pair copulation in Razorbill mating strategies

Wagner, Richard Howard January 1991 (has links)
No description available.
9

Sexual selection and mating systems in Bufo rangeri and Bufo pardalis

Cherry, Michael Ian January 1989 (has links)
No description available.
10

Characterisation of a yeast silencer sequence

Brand, A. H. January 1986 (has links)
No description available.

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