Mapping the evolutionary accessible space in yeast

Tradeoffs constrain the improvement of performance of all traits simultaneously. Such tradeoffs define a Pareto optimality front that represents a set of optimal individuals that cannot be improved in any one trait without reducing performance in another trait. While widely assumed, direct experimental evolutionary approaches often fail to detect tradeoffs with many experiments generating individuals that improve performance in all measured traits. Moreover, even when an improvement in one trait is found to be associated with the loss of performance in another trait, it is hard to establish that such a negative correlation is not induced by specific sampled mutations and that other possible adaptive mutations might be able to escape such apparent tradeoffs. Here we attempt to detect tradeoffs and define the Pareto optimality front in the context of short-term evolution of S. cerevisiae in glucose-limited media.