Commendation for Dr Lucy Turner - School of Biological Sciences

Supervisor: Dr Marian Yallop

Funding: NERC Studentship

PhD project: A role for Crustacean Hyperglycaemic Hormone (CHH) in the regulation of kidney-like function in freshwater land crabs: A study of the Christmas Island Blue Crab, Discoplax hirtipes

Dr Lucy Turner undertook the first study on the seasonal role of crustacean hyperglycaemic hormone (CHH) on the control of osmoregulation in the Indo-Pacific distributed freshwater land crab Discoplax hirtipes. The role that peptide hormones (CHH) play in switching on or off the excretion and re-absorption of salt and water was examined, i.e. how much water is drunk and how much urine is produced, and also how the gills function in a 'kidney-like fashion' reclaiming essential salts from the urine. The evolution and development of a kidney-like organ is essential in the colonisation of land and fundamental for air-breathing animals. Discoplax hirtipes is a land crab but as with many land animals requires access to a supply of fresh water. This highlights the fact that D. hirtipes can be considered an intermediate in the lineage of water to air-breathing crabs, thus adding a further interesting dimension to her research. Indeed, these ecological features are the reason why this species was selected for the work. Thus, her work simultaneously addressed specific issues of the control of water and salt uptake by hormones and broader questions concerning how life evolved from the ocean to inhabit the land.

She made several field trips to Christmas Island during her PhD to conduct her sampling and run her experiments. The timing of these field trips was crucial since they coincided with the dry and wet (which is also the time at which the animals migrate to the ocean for breeding) seasons; fundamental issues in a project examining salt and water balance.

During her work, phylogenetic analysis of CHH identified that this crab is a very recently evolved freshwater land crab, having evolved via freshwater rather than directly from the marine environment. These findings have a wider relevance for understanding the colonisation of land by aquatic crustaceans.

During her PhD she presented three papers at international conferences in the Maasai Mara in Kenya, Prague and Glasgow. Since then she has been an invited speaker at the Plymouth University School of Biomedical and Biological Sciences Exploration Biology Lecture Series. She has published two papers from her PhD with another two close to completion.

Biography

I grew up near Bournemouth on the Dorset coast and had always been fascinated by the ocean and all things marine related. I studied for my first degree in Marine Biology at the University of Wales, Swansea. Whist I was at Swansea I had to opportunity to undertake fieldwork in Indonesia on nudibranchs (colourful marine sea slugs). This was the first time I had been to the tropics and it also gave me my first introduction to land crabs (they used to emerge after dusk and steal our shoes!). Undertaking my own research made me realise that I wanted to peruse a research career, and so after a year out following graduation I went to Plymouth University to study for an MRes. I was drawn to Bristol to study for my PhD primarily because of my desire to study land crabs with my supervisor (the late Prof Steve Morris). I was also fortunate to obtain a NERC studentship which also allowed me to collaborate with Prof Simon Webster at Bangor University. My PhD was a mixture of molecular work, physiology and ecology and I really valued the integrated approach I was able to take. I learnt so much and so many new skills during my studies at Bristol University and this has stood me in good stead for my future career. I am now working as a Research Assistant at the Marine Biology and Ecology Research Centre at Plymouth University where I have so far worked on several different topics, including multiple paternity in lake Malawi cichlids, the response of freshwater diving beetles to climate change and the effects of ocean acidification on marine invertebrates. Since my PhD I have successfully bid for funding from the British Ecological Society and Society of Experimental Biology to return to Christmas Island. This is enabling me to add valuable data to my existing datasets as well as to explore some new lines of research on the land crabs of Christmas Island with colleagues from the Marine Biology and Ecology Research Centre at Plymouth University. Ultimately I would like to understand more about the evolution of life from the marine to the terrestrial environment by understanding more about the mechanisms (including the role of peptide hormones) that allow organisms to cope with the extreme challenges this involves, and land crabs are a great model to study this.