About the Authors
Division of Biology, University of California San Diego, La Jolla, California, United States of America
Institute of Integrative Biology, Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
INSERM U722, Faculté de Médecine Xavier Bichat, Paris, France
Université Paris 7, Paris, France
The authors have declared that no competing interests exist.
OKS, OT, and LC contributed to the conception of the experiments. OKS and OT performed the experimental evolution and the mutation accumulation. OKS performed the maximum likelihood analysis of the mutation accumulation data and the analysis of the sequence data. OT performed the simulation analyses of substitution rates.