Emily Glendenning – Research Technician
I am originally from Otley, West Yorkshire and recently graduated with a degree in Biology at the University at Sheffield. I came to work with the TRB research group in 2012 when I undertook a summer placement in the laboratory working for Dr Nicola Hemmings. I then completed my third year and fourth year (masters year) research projects and a second summer research assistant placement in the group. I am currently employed full-time as a Research Technician in the TRB lab, working on a project exploring the problem of sperm dilution. I am particularly interested in the role of female behaviour and anatomy in the lead up to fertilisation.
My third year research project aimed to explore whether selection for divergent sperm length in zebra finches inadvertently selected for other traits, such as male mating behaviours and female sperm storage capacity.
My masters research project aimed to explore the occurence, causes and consequences of sperm DNA fragmentation in birds. I adapted a sperm DNA damage assay regularly used in mammalian research for use on bird sperm using zebra finches as a study model.
In 2014 I had the opportunity to apply the assay to a number of raptor species at a falcon breeding facility in Carmarthen, Wales (See the article here). As part of a collaboration with International Wildlife Consultants UK Ltd, I had access to sperm samples being used for artificial inseminations of peregrine and gyr falcons. Data on sperm DNA fragmentation will be collated with morphology, abnormality, concentration and motility data as well as hatching success and embryo mortality data to give the breeding facility sperm quality indices for each of their stud males.
The DNA fragmentation assay was also applied to answer a number of hypotheses in zebra finches, such as whether, and where, poor quality sperm are filtered from the ejaculate on the journey between the testes and ova.
I am currently working on a project investigating the theory of ‘sperm dilution’ in birds. Sperm dilution could occur where, as species get larger, their testes size (and therefore sperm production ability) increases with negative allometry. This knowledge, coupled with the assumption that oviduct sizes increase relative to body sizes, could result in a situation where, as as species get larger, sperm production does not change in relation to the distance sperm have to travel to reach the ova. It would therefore be assumed that larger bodied species are disadvantaged in regards to sperm transport. I am using a number of Galliforme species as a study model to test hypotheses that may explain how larger bodied bird species may overcome the problem of sperm dilution.
Away from the lab, I draw commissioned pet portraits (www.facebook.com/emglenart/) and I play football for Battyeford Belles.