Sustained fitness gains and variability in fitness trajectories in the long-term evolution experiment with Escherichia coli.

ABSTRACT: Many populations live in environments subject to frequent biotic and abiotic changes. Nonetheless, it is interesting to ask whether an evolving population's mean fitness can increase indefinitely, and potentially without any limit, even in a constant environment. A recent study showed that fitness trajectories of Escherichia coli populations over 50 000 generations were better described by a power-law model than by a hyperbolic model. According to the power-law model, the rate of fitness gain declines over time but fitness has no upper limit, whereas the hyperbolic model implies a hard limit. Here, we examine whether the previously estimated power-law model predicts the fitness trajectory for an additional 10 000 generations. To that end, we conducted more than 1100 new competitive fitness

SUBMITTER: Lenski RE 

PROVIDER: S-EPMC4707762 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature