Georgia Institute of Technology College of Sciences

We develop mathematical models describing the evolutionary dynamics of asexual and sexual reproduction pathways based on the yeast life cycle. By explicitly considering the semiconservative nature of DNA replication and a diploid genome, we are able to obtain a selective advantage for sex under much more general conditions than required by previous models. We are also able to suggest an evolutionary basis for the use of sex as a stress response in unicellular organisms such as Baker's yeast. Some additional features associated with both asexual and sexual aspects of the cell life cycle also fall out of our work. Finally, our work suggests that sex and diploidy may be useful as generalized strategies for preventing information degredation in replicating systems, and may therefore have applications beyond biology.