How does sexual selection shape sperm form and function? (GAGE_UBIO16EE) How does sexual selection shape sperm form and function? (GAGE_UBIO16EE)

Primary Supervisor: Prof Matthew Gage (https://www.uea.ac.uk/biological-sciences/people/profile/m-gagem.gage@uea.ac.uk).

Project Description

Sperm have one main function: to transport the male haplotype for fusion with the egg. This function, and its male:female specificity, is an important foundation in biodiversity. Despite this uniform function, spermatozoa are the most diverse and complex eukaryotic cells known. Even simple size can vary enormously, from the 6cm-long giant sperm of Drosophila bifurca down to the porcupine’s tiny 28µm gamete. Huge diversity also exists in sperm morphology and behaviour. We understand remarkably little about what drives spermatozoal diversity, so this studentship aims to improve on that.

Sexual selection, when males compete and females choose within reproduction, is likely to be an important agent in the evolution of sperm form and function. We will take advantage of some unique experimentally-evolved lines of the flour beetle, Tribolium castaneum, which have been specifically bred by us under very different intensities of sexual selection for ~10 years. The lines have clearly diverged in traits related to winning fertilizations under sperm competition, providing an excellent basis to now measure how sperm form and function have changed alongside.

Using careful experimental design, microdissection, advanced microscopy and cell fluorescent imaging and sperm analysis techniques, we will measure how sperm form and function has diverged after high and low sexual selection, both in vitro and in vivo within the natural environment of the female reproductive tract (see images). GFP and RFP lines will allow us to study the interactions of sperm from up to three different males as they behave and compete within the female tract.

The student will join an active and productive research team interested in the evolution of reproductive function (more details:https://www.uea.ac.uk/biological-sciences/people/profile/m-gage#researchTab). You will join an energetic PhD cohort, and receive generic and specific training in a range of skills that will allow you to develop into an independent researcher, and publish high quality, international impact science. You should have a good MSc or BSc degree, or equivalent, in a relevant subject area, and be keen to make fundamental advances in an area of evolutionary biology that is poorly understood.

References:

i) Gage MJG (2012) Complex sperm evolution. Proc Natl Acad Sci USA 109, 4341-4342.

ii) Lumley AJ, Michalczyk Ł, Kitson JJN, Spurgin LG, Morrison CA, Godwin JL, Dickinson ME, Martin OY, Emerson BC, Chapman T & Gage MJG (2015) Sexual selection protects against extinction.Nature 522, 470-473.

iii) Michalczyk Ł, Martin, OY, Millard AL, Lumley, AJ, Emerson BC & Gage MJG (2011b) Experimental evolution exposes female and male responses to sexual selection and conflict in Tribolium castaneum. Evolution 65, 713-724.

iv) Michalczyk Ł, Millard AL, Lumley AJ, Martin OY, 3. Emerson BC, Chapman T & Gage MJG (2011a) Inbreeding promotes female promiscuity. Science 333, 1739-1742.

Deadline: 23:59 on Wednesday 6 January 2016

Start date: October 2016
Programme: PhD
Mode of Study: Full Time
Entry Requirements: Acceptable First Degree: Biology, Ecology, Genetics, Zoology, or other relevant subject
Minimum Entry Standard: 2:1

For further information and to apply, please visit our website: https://www.uea.ac.uk/study/postgraduate/apply.