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You searched for +publisher:"University of New South Wales" +contributor:("Ord, Terry, Evolution & Ecology Research Centre, Faculty of Science, UNSW"). Showing records 1 – 2 of 2 total matches.

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University of New South Wales

1. Morgans, Courtney. Studies of natural selection and sexual selection on an unusual tropical land fish.

Degree: Evolution & Ecology Research Centre, 2013, University of New South Wales

My thesis aimed to investigate the influence of selection on an animal invading a novel habitat and how subsequent differences in natural selection, sexual selection and genetic drift might influence phenotypic variation among populations. The Pacific leaping blenny on Guam (Alticus arnoldorum) provided a novel opportunity to address these aims as it has made one of the most extreme ecological transitions possible, it is a fish that lives its entire adult life on land. Furthermore, the presence of multiple populations of this fish around the island allowed the investigation of how differences in selection pressures and gene flow might generate or limit phenotypic variation between populations that otherwise occupy the same broad habitat type (intertidal rocks on land). First, I examined the influence of natural selection in the form of predation on colonising a novel environment (here, a shift onto land). The colouration of male and female blennies from five populations was examined along with the colour of their respective backgrounds. I found the body colour of all populations closely resembled the habitat on land. A subsequent predation experiment confirmed that this background matching functioned to reduce predation and was therefore adaptive. These results suggested that closely resembling the colour of habitat backgrounds has probably aided the Pacific leaping blenny in successfully colonising land. Second, I examined the relative influence of natural selection (predation), sexual selection and gene flow on phenotypic variation among populations on land. Results suggested that variation in natural selection and sexual selection had a predictable influence on phenotypic expression: sexual selection has promoted the exaggeration of ornaments, while natural selection has reduced the conspicuousness of these features. Most notably, this population divergence in ornamentation has occurred despite high gene flow. Overall, my thesis demonstrates how adopting an integrative approach is essential for isolating the mechanisms leading to phenotypic divergence during the invasion of new environments, and how populations can subsequently diverge in response to variation in social factors and predation once colonisation has occurred. Advisors/Committee Members: Ord, Terry, Evolution & Ecology Research Centre, Faculty of Science, UNSW.

Subjects/Keywords: Sexual selection; Alticus arnoldorum; Natural selection; Pacific Leaping Blenny; Phenotypic variation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Morgans, C. (2013). Studies of natural selection and sexual selection on an unusual tropical land fish. (Masters Thesis). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52874 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11552/SOURCE01?view=true

Chicago Manual of Style (16th Edition):

Morgans, Courtney. “Studies of natural selection and sexual selection on an unusual tropical land fish.” 2013. Masters Thesis, University of New South Wales. Accessed April 05, 2020. http://handle.unsw.edu.au/1959.4/52874 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11552/SOURCE01?view=true.

MLA Handbook (7th Edition):

Morgans, Courtney. “Studies of natural selection and sexual selection on an unusual tropical land fish.” 2013. Web. 05 Apr 2020.

Vancouver:

Morgans C. Studies of natural selection and sexual selection on an unusual tropical land fish. [Internet] [Masters thesis]. University of New South Wales; 2013. [cited 2020 Apr 05]. Available from: http://handle.unsw.edu.au/1959.4/52874 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11552/SOURCE01?view=true.

Council of Science Editors:

Morgans C. Studies of natural selection and sexual selection on an unusual tropical land fish. [Masters Thesis]. University of New South Wales; 2013. Available from: http://handle.unsw.edu.au/1959.4/52874 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11552/SOURCE01?view=true


University of New South Wales

2. Klomp, Danielle Alice. The Evolution of Diversity: Sexual selection and natural selection on the social signals of gliding lizards.

Degree: Biological, Earth & Environmental Sciences, 2016, University of New South Wales

Diversity in animal colour and form can often be attributed to communication signals, which play an important role in species recognition and mate choice. Divergence of signals among populations is therefore thought to be a driver of speciation. This thesis examines signalling processes in the species rich agamid genus, Draco, to understand their influence on signal design, signal divergence and ultimately speciation. Draco lizards are known as ‘gliding lizards’, as they have retractable gliding membranes. They communicate with extendable throat-fans, called dewlaps, which are diverse in colour, shape and size among species. Chapter two assesses the importance of dewlap signal design for detection and recognition in Draco melanopogon, by presenting free-living lizards with robots displaying dewlaps of different designs. Dewlap design does not affect the latency of signal detection by conspecifics, but once the robot dewlap had been detected, males responded with greater intensity to dewlaps that best resembled the species’ typical design, suggesting pattern is important in species recognition. As signal components may evolve differently in populations exposed to different selection pressures, chapter three assess the relationships between the dewlap components (colour and size) and aspects of their environments. Males of different species employ colour contrast and dewlap size as alternative strategies for effective communication, and predation intensity may play a role in which strategy a species employs. Further, correlations between male dewlap components and sexual dimorphism suggest that sexual selection is also a major factor influencing dewlap design. Chapter four shows that the different gliding membrane colouration of two populations of Draco cornutus closely match the colours of freshly fallen leaves in their respective habitats as they appear to the visual system of predatory birds. This suggests the populations have diverged in colouration to mimic the colours of local falling leaves and thereby reduce predation by birds. Chapter five tests whether Draco sumatranus lizards use their position relative to the sun to enhance the transmission of light through the dewlap, and thus the apparent brightness of their dewlap during display. Lizards are significantly more likely to orientate themselves perpendicular to the sun when displaying, ensuring maximum sun exposure for the extended dewlap. This thesis confirms the centrality of sexual selection, species recognition and predation as major factors influencing signal design in Draco, and thereby furthers our understanding of the evolution of ornament diversity. Advisors/Committee Members: Ord, Terry, Evolution & Ecology Research Centre, Faculty of Science, UNSW, Stuart-Fox, Devi, School of BioSciences, University of Melbourne.

Subjects/Keywords: Sexual selection; Lizards; Natural selection

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Klomp, D. A. (2016). The Evolution of Diversity: Sexual selection and natural selection on the social signals of gliding lizards. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/56914 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42030/SOURCE02?view=true

Chicago Manual of Style (16th Edition):

Klomp, Danielle Alice. “The Evolution of Diversity: Sexual selection and natural selection on the social signals of gliding lizards.” 2016. Doctoral Dissertation, University of New South Wales. Accessed April 05, 2020. http://handle.unsw.edu.au/1959.4/56914 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42030/SOURCE02?view=true.

MLA Handbook (7th Edition):

Klomp, Danielle Alice. “The Evolution of Diversity: Sexual selection and natural selection on the social signals of gliding lizards.” 2016. Web. 05 Apr 2020.

Vancouver:

Klomp DA. The Evolution of Diversity: Sexual selection and natural selection on the social signals of gliding lizards. [Internet] [Doctoral dissertation]. University of New South Wales; 2016. [cited 2020 Apr 05]. Available from: http://handle.unsw.edu.au/1959.4/56914 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42030/SOURCE02?view=true.

Council of Science Editors:

Klomp DA. The Evolution of Diversity: Sexual selection and natural selection on the social signals of gliding lizards. [Doctoral Dissertation]. University of New South Wales; 2016. Available from: http://handle.unsw.edu.au/1959.4/56914 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42030/SOURCE02?view=true

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