PhD Studentship: Effects of ocean acidification on shell characteristics in articulated brachiopods

NERC PhD studentship funded by NERC grant NE/I019565/1: Shell composition and microstructure variation with pH in time and space.

Supervisors: Prof Lloyd Peck (BAS) & Dr Elizabeth Harper (Earth Sciences, Cambridge).

Full studentship funding is limited to UK and some EU citizens. For more details see
http://www.nerc.ac.uk/funding/available/postgrad/eligibility.asp

This PhD project forms part of a large, interdisciplinary research project to assess the impact of ocean acidification on life in the sea. It is in turn part of the NERC Thematic Programme to investigate biodiversity and ecosystem functioning on the planet. This project aims to address 4 questions:

1. How do shell microstructure and composition vary between animals currently living at different pH?
2. How do these shell characteristics vary within a species from the same site across the Anthropocene?
3. How do shell characteristics vary in brachiopods across geological periods with different CO2 levels?
4. How does growing articulated brachiopods in lowered pH conditions alter their shell characteristics?

This studentship will investigate how shell thickness, primary & secondary layer thickness, crystal morphology, major & minor elements varies in articulated brachiopods across a range of spatial and temporal scales. There will be four main approaches: 1. Evaluating differences between shells of brachiopods from the same species living in different sites with different current pH regimes. This work will be aimed at analyzing shells of Terebratulina retusa in Scotland, and Calloria inconspicua from New Zealand, in both cases comparing animals from nearshore sites such as fiords and open offshore localities. 2. Assessing the effects of holding specimens in experimental systems in Plymouth and BAS Cambridge with altered pH. Here specimens of T. retusa and the Antarctic Liothyrella uva will be held at low pH for periods of 3-6 months and the effects of lowered pH on shells examined. 3. Shell characteristics of samples from the last 150 yr held in museums will be analysed to assess how changing global CO2 levels, and hence altered pH in the sea. 4. Brachiopod shells from past geological periods with different global CO2 regimes will be compared to identify long-term, evolutionary scale responses to altered pH.

The project is wide ranging in its practical requirements and training. It will involve fieldwork collecting specimens and the maintenance of laboratory experimental aquarium systems with altered pH. Much of the work, however, will be the analysis of shell characteristics. Shells will be embedded, sectioned, polished and etched before analyzing for shell layer thickness and dimensions of secondary layer crystals. Caecal density will also be analysed from cleaned whole shells, and elemental composition will also be analysed on a Cameca SX-100 ion probe.

Candidates should have a background in the mainstream biological/palaeobiological sciences and be able to demonstrate a strong relevant research interest. Masters level experience would be advantageous. Applicants should submit an expression of interest (max 2 pages), CV and the emails of two referees.

Enquiries to: Alison Teague, BAS alag@bas.ac.uk Closing date for applications: 10.2.12
http://www.antarctica.ac.uk/employment/vacancies/job.php?JobID=694