Chris+Marx

**Christopher Marx** Department of Organismic and Evolutionary Biology FAS Center for Systems Biology Harvard University cmarx@oeb.harvard.edu

My laboratory uses experimental evolution as an approach to address the selective pressures and varied outcomes of adaptation of microbial populations. Current projects include (pasted from my website):
 * Systems-level physiological basis of selection and epistasis in adaptation of strains bearing engineered horizontal gene transfers. Can we move toward being able to quantitatively predict the probability of various evolutionary outcomes, and how the mutations along these trajectories interact?
 * Experimental evolution of multi-species, synthetic consortia to integrate studies of the physiological, ecological and evolutionary aspects of cooperation and coevolution in microbial communities. Can metabolic models guide predictions as to the function and adaptation of novel assemblages, particularly conditions where costly cooperation is selectively advantageous?
 * Distribution of fitness effects, identity and interaction of beneficial mutations available for adaptation. How can we characterize the raw material available for adaptation and how this changes as adaptation to a particular environment slows down?
 * Investigation of fitness tradeoffs and adaptive diversification associated with specialist vs. generalist lifestyles. Can we predict when to utilize more than one substrate simultaneously vs. forming independent ecotypes?
 * Transposable elements as key variation in adaptation. What roles do mobile elements play in the evolution of laboratory and natural populations?
 * Balance of costs and benefits associated with gene expression and codon usage. What drives selection upon codon usage in genomes?
 * Physiological function of hopanoids in //Methylobacterium//. What role do these key geological biomarkers play in this present-day model organism, and what inferences can thus be drawn about ancient environments?

I'll be at KITP through Friday the 7th and would love to chat if you have interest in any of the above...

Or if you are interested in grabbing a good beer, I'll be doing my best to agitate in that regard, too.