Direct and correlated fitness responses of the replicate populations in each group. Panels labelled glu(mal) and glu(lac) correspond to the same glucose-evolved populations but assayed in resource environments comprising the glu&mal or glu&lac sets, respectively. Each point is the mean of five fitness assays. Lines connect the same population across the different environments.
Cooper and Lenski BMC Evolutionary Biology 2010 10:11 doi:10.1186/1471-2148-10-11