The Origin and History of Life on Earth

Evolutionary studies can help us to understand more about the history of life on earth. Different approaches are used to examine these questions depending on the timescales and the areas of interest (for example, questions about the origins of life versus the emergence of specific organs or specific adaptations).

Our work is broadly divided to study two different questions: What can evolution tell us about the origins of life on earth? What can evolution tell us about the origins of specific adaptations and how can we apply this experimentally or industrially?

The Early History of Life

The Temperature History of Life

Features of the physical environment surrounding an ancestral organism can be inferred by reconstructing sequences of ancient proteins made by those organisms, resurrecting these proteins in the laboratory, and measuring their properties. Our studies suggest that the ancestors of modern life were thermophiles (heat-loving). (NASA)

Gaucher, EA et al. Nature 425 285-288 (2003)

Elongation factors

Developing biologically relevant models of sequence evolution and coupling these with structural and molecular biology to identify sites that are likely to be involved in changing function within a gene family is required to understand molecular function/behavior. Our studies highlight the importance of this method to identify unique protein binding domains and extract information related to divergent evolution.

Gaucher, EA et al. TIBS 27 315-321 (2002)

The Evolutionary History of Specific Adaptations

The origins of fermentation

We exploited techniques in paleobiochemistry to resurrect enzymes involved in alcohol fermentation to understand the relationship of fermentable fruit and yeast in the age of the Dinosaurs. Our results help to connect the chemical behavior of these enzymes through systems analysis to a time of global ecosystem change, and highlights the utility of 'planetary systems biology'. (NASA)

Thomson, JM et al. Nature Genet. 37 630-635 (2005)

Adaptations of aromatase in pigs

Joining a model for the molecular evolution of a protein family to the paleontological and geological records, and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy was adopted to understand reproductive strategies during mammalian speciation events. (NIH)

Gaucher, EA et al. BMC Biology 2 19 (2004)