Sexual selection is underpinned by variation in reproductive success. My research aims to understand the causes of this variation at the post-copulatory level, using birds as a model. I have developed several techniques to help me do this, including (i) discriminating between fertilisation failure and early embryo mortality (Hemmings et al. 2012), (ii) characterising sperm sub-populations (Hemmings et al. 2015; Bennison, Hemmings et al. 2016), (iii) quantifying sperm penetration rates and locating sperm pronuclei in ova (Hemmings & Birkhead 2015), and (iv) imaging sperm-female interactions in vivo (Mendonca & Hemmings in prep). A full list of my publications can be found here.
My current work focuses on the causes of female reproductive failure. Birds provide an excellent study system for several reasons: They produce relatively large eggs in which the embryos develop, outside of the mother’s body, facilitating experimental study; failed eggs can be analysed using novel techniques to understand the underlying reproductive problem(s); and a wealth of long-term data exists on variation in female reproductive success, within and between individuals, populations, and species.
My goals are to elucidate the genetic and/or developmental basis of female reproductive failure, establish how it is maintained despite strong selection for success, and understand how it interacts with male reproductive success and environmental pressures. This work – which is supported by several fantastic collaborators – will provide insight into the evolution of female reproductive traits, as well as allowing us to make predictions about how our changing environment might shape reproductive success in the future.
Much of my work on reproductive failure in birds has important implications for conservation, and I have been fortunate to work with a number of UK and international conservation organisations including the RSPB, Wetlands & Wildfowl Trust, Hihi Recovery Group (New Zealand), Zoos Victoria (Australia), and Al Wabra Wildlife Preservation (Qatar).