Indeed, a recent study of long-term experimental evolution in E. coli unmasking DNA topology as a key target for selection identified fitness-enhancing mutations in topoisomerase and fis genes [ 27].
We also identify fitness tradeoffs, in the form of male survivorship and female fecundity, which accompany adaptation to social selection.
The survival of the ancestral pathogen until today suggests that its genetic attributes could be informative in identifying fitness and potentially pathogenic loci.
To identify fitness consequences of social selection, wild-derived mice that had bred under laboratory conditions for eight generations were re-introduced to naturalistic competition in enclosures for three consecutive generations (promiscuous line).
Although this study did not identify fitness costs, further work to characterize the potential impact of fitness costs in a population based setting is needed, since the presence of fitness costs is a commonly-made assumption in research on antimicrobial resistance, in particular in relation to the disappearance of resistant bacteria in the absence of antimicrobial drug.
We tested the method by identifying fitness- and sensitivity-based interactions involved in the response to drug-induced DNA-damage of budding yeast Saccharomyces cerevisiae using two mutant libraries - one containing transcription factor deletions, and the other containing deletions of DNA repair genes.
Generally, more than two populations are needed to differentiate effects of local adaptation from the effects of drift or migration, causing similar population-by-habitat interactions [ 2], and only replication on the population level allows for identifying fitness differences caused by divergent selection.
We have identified inclusive fitness benefits of this behaviour in L. kintorei, which, given the few examples of sociality in lizards, would also seem to explain its rarity.
Notably, only ~50% of the interactions identified using fitness phenotypes are also among those identified using sensitivity.
Noticeably, within the TF dataset analyzed, as few as ~50% of the interactions identified using fitness phenotypes are also identified using sensitivity.
