Evolution of microplankton in a changing ocean

Project Details

Key Questions

How does adaptation process work in extremely large populations generally and how it works in marine phytoplankton specifically? 

Background

The processes of new species formation and adaptation to changing environment have been studied to some extent for relatively small populations of terrestrial organisms. Much less is known about evolutionary processes in astronomically large populations of marine phytoplankton that inhabit relatively homogenous and stable environment. Yet, on-going climate warming drives rapid change in that stable environment and it remains unclear whether and how the extremely ecologically important primary producers of the ocean can adapt to this rapid change. This project aims to shed light on this question.  

Aims of the Project

The project aims to understand evolutionary genetic processes in extremely large populations, such as found in marine plankton. More specifically, it aims to understand how phytoplankton adapts to on-going rapid climate warming and ocean acidification 

Project Description

The focus of evolutionary genetics over the last half a century has been on relatively small populations of terrestrial organisms. Much less is known about microevolutionary processes in extremely large populations, such as found in marine phytoplankton. Photosynthesis in marine phytoplankton is responsible for about half of newly produced organic matter on the planet. The amount of CO2 they fix in this process is thought to significantly affect the global carbon cycle and climate. Given the paramount ecological importance of marine ecosystems generally and the phytoplankton specifically, the lack of understanding of microevolutionary processes in large plankton populations is unfortunate. To fill this gap we will study adaptation and speciation processes in the ‘model’ coccolithophore Emiliania huxleyi and its close relatives in Gephyrocapsa genus. Other phytoplankton, such as the diatom genus Chaetoceros, will also be used, whenever possible, to test the generality of the conclusions. Whole-genome sequencing of multiple strains and environmental metagenomics will be used to analyse and compare evolutionary genetic histories in these genera. The availability of extensive culture collection of strains sampled across the globe, and the record of global climatic oscillations in late Quaternary make these genera ideal evolutionary genetic models to study adaptation and speciation processes in marine phytoplankton. Furthermore, detailed fossil record available for mineralising phytoplankton will allow us to combine and compare the histories of adaptation and speciation recorded in the genes and the fossil record of these predominant phytoplankton species. This interdisciplinary approach has the potential to significantly advance our understanding of how the new species of phytoplankton form and how they adapt to changing environments, such as climatic oscillations during glacial cycles or human-mediated climate change. 

Methods to be used

Evolutionary genetic analyses of genome sequence data from multiple phytoplankton strains of closely related species 

Specialised skills required

The student will be involved in processing and analysis of large volumes of genome sequence data. This will involve some programming and/or scripting in unix environment.

Please contact Prof. Dmitry A. Filatov on Dmitry.Filatov@plants.ox.ac.uk if you are interested in this project