Ros Rickaby

I am fascinated by the jigsaw of complex interactions between the evolution of organisms, ocean chemistry, atmospheric composition and Earth’s climate. The extraction of chemical signatures from fossil shells of marine micro-organisms as a tool for constraining past ocean conditions and their influence on climate is fundamental to my research. Yet frustration with the complexities of disentangling the “inorganic” geochemical signal from the overprint of the biomineralising processes has triggered me to seek innovative alternative approaches to constraining past climates and environments. Increasingly I am probing the geological past from the biology of modern day organisms. This ambition broadens into probing biological innovation and environmental change over Earth history since the feedback between the two is inescapable. All modern day organisms have experienced a long evolutionary pathway to arrive at their present incarnation and this history has been accrued to some extent within the genome and physiology of modern day organisms. Indeed such evolutionary history influences the tolerance of different algae to ocean acidification for example, or the trace metal nutrient requirements of different groups of algae across the tree of life. So my approach is to read the geological history of both climate and the chemical environment from signals of adaptation within genes, which plays out in the evolving affinity and kinetics of the expressed enzymes, or isotopic signals of adaptation within biologically relevant molecules.

I lead the OceanBUG research group and my quest for a new proxy based on biological understanding of the signal is reflected in our current projects which include:

Species-specific coccolithophore response to ocean acidification
Lifting the CAP on coccolithophore calcification: characterising acidic polysaccharides which mould the calcite liths of coccolithophores as probes of the past carbon environment
Squelching into the fine mud: dissecting the fine fractions of sediments to read the physiological controls on the isotopes of both coccoliths and diatoms
Characterisation of modern and ancient algal Rubisco with implications for carbon isotopes and acquisition

I spoke about aspects of my work as part of the Royal Society’s Science Stories series:

Most recently we were involved in an interdisciplinary exhibit at the Royal Society Summer Science Exhibition celebrating 150 years of the Periodic Table and what it means for life on earth. Follow the link for more information and a chemical crossword!

https://warwick.ac.uk/fac/sci/chemistry/inyourelement/theperiodictableoflife/