Post-doctoral Research Associate

Current Work – Sperm production costs in birds

University of Sheffield

Starting my undergraduate degree in Sheffield created a link with the Animal and Plant Sciences Department that has endured for over a decade. A large proportion of that time has been spent in the NERC funded molecular ecology facility under the supervision of Professors Terry Burke and Jon Slate. However, after studying for my PhD at the University of Bath, where my interests in both genetics and sperm competition were combined, I now find myself working on an exciting new project in Tim Birkhead’s lab.


My PhD under the supervision of Prof. Tamas Szekely & Dr. Steve Dorus allowed me great independence in pursuing research on pre and post-copulatory sexual selection in a passerine group that is known for its promiscuous mating systems. The penduline tits (Remizidae) are a small group of passerines closely related to the true tits (Paridae), see photo below of one of my study species, the smallest bird in Africa (Anthoscopus minutus). I performed comparative analyses across species to study the evolution of various sexually selected traits in this family, particularly focusing on the relationship between plumage and sperm traits that impact reproductive success. My interests in the trade-offs between pre and post-copulatory traits has stemmed from this initial work and the next logical step was to investigate the energetic costs of these traits.

penduline tit sperm

Knowledge on the energetic costs and timings involved in sperm production is sparse in birds and virtually non-existent in passerines. By developing novel techniques to measure variations in sperm production across birds I hope to develop a more detailed understanding of spermatogenesis. The main body of the project will focus on the use of a captive zebra finch population in which two artificial selection lines have been developed, one with long and one with short sperm lengths. However, this work will be put into a broader context by studying testes and sperm traits across a diverse array of species, including both galliforms and passerines.

This work fits well with my broad interests in sexual selection and complements my previous molecular work on the genetics of passerine birds, including the zebra finch. My initial focus in genetics stemmed from my interest in conservation and the impact of population declines on the underlying genetics of a species. This still fuels a lot of my ideas and I hope to apply this training in genetics during future research.



Dawson D. A., Bird S., Horsburgh G. J., Ball A. D. (2015) Autosomal and Z-linked microsatellite markers enhanced for cross-species utility and assessed in a range of birds, including species of conservation concern. Conservation Genetics Resources In press.

Dawson, D. A., Ball, A. D., Spurgin, L. G., Martin-Galvez, D., Stewart, I. R. K., Horsburgh, G. J., Potter, J., Molina-Morales, M., Bicknell, A. W. J., Hodges, S., Ekblom, R., Slate, J., Burke, T. (2013). High-utility conserved avian microsatellite markers enable parentage and population studies across a wide range of species. BMC Genomics 14:176.

Dawson, D. A., Horsburgh, G. J., Krupa, A. P., Stewart, I. R., Skjelseth, S., Jensen, H., Ball, A. D., Spurgin, L. G., Mannarelli, M. E., Nakagawa, S., Schroeder, J., Vangestel, C., Hinten, G. N., Burke, T. (2012). Microsatellite resources for Passeridae species: a predicted microsatellite map of the house sparrow, Passer domesticus. Molecular Ecology Resources 12(3): 501-523.

Ekblom, R., Stapley, J., Ball, A. D., Birkhead, T., Burke, T., Slate, J. (2011). Genetic mapping of the major histocompatibility complex in the zebra finch (Taeniopygia guttata). Immunogenetics 63(8): 523-530.

Ball, A. D., Stapley, J., Dawson, D. A., Birkhead, T. R., Burke, T., Slate, J. (2010). A comparison of SNPs and microsatellites as linkage mapping markers: lessons from the zebra finch (Taeniopygia guttata). BMC Genomics 11:218.

Stapley, J., Reger, J., Feulner, P. G. D., Smadja, C., Galindo, J., Ekblom, R., Bennison, C., Ball, A. D., Beckerman, A. P., Slate, J. (2010). Adaptation genomics: the next generation. Trends in Ecology & Evolution 25(12):705-712.

Slate, J., Santure, A. W., Feulner, P. G. D., Brown, E. A., Ball, A. D., Johnston, S. E., Gratten, J. (2010). Genome mapping in intensively studied wild vertebrate populations. Trends in Genetics 26(6): 275-284.

Dawson, D. A., Horsburgh, G. J., Kupper, C., Stewart, I. R. K., Ball, A. D., Durrant, K. L., Hansson, B, Bacon, I,. Bird, S., Klein, A., Krupa, A. P., Lee, J., Martin-Galvez, D., Simeoni, M., Smith, G., Spurgin, L. G., Burke, T. (2010). New methods to identify conserved microsatellite loci and develop primer sets of high cross-species utility – as demonstrated for birds. Molecular Ecology Resources 10(3): 475-494.

Santure, A. W., Stapley, J., Ball, A. D., Birkhead, T. R., Burke, T., Slate, J. (2010). On the use of large marker panels to estimate inbreeding and relatedness: empirical and simulation studies of a pedigreed zebra finch population typed at 771 SNPs. Molecular Ecology 19(7): 1439-1451.



The ‘costs’ of avian sperm. BoS Biennial Meeting 2015, The Peak District, UK.

Sexual conflict in the penduline tits: the evolution of sexual dimorphism. PopGroup46, 2013, Glasgow, UK.

Sexual selection drives evolution: inferring phylogeny and trait evolution in the penduline tits (Remizidae). ESEB 2013, Lisbon, Portugal. (Poster)

Inferring phylogeny and trait evolution in a diverse avian family, the penduline tits (Remizidae). PopGroup45, 2012, Nottingham, UK. (Poster)