Evidence is mounting that epistasis is widespread among mutations. The cost of carrying
two deleterious mutations, or the advantage of acquiring two beneficial alleles, is typically …

Background Evolution in one selective environment often latently generates phenotypic
change that is manifested only later in different environments, but the complexity of behavior …

The fitness effects of mutations can depend on the genetic backgrounds in which they occur
and thereby influence future opportunities for evolving populations. In particular, mutations …

Beneficial mutations can become costly following an environmental change. Compensatory
mutations can relieve these costs, while not affecting the selected function, so that the …

Populations of Escherichia coli selected in constant and fluctuating environments containing
lactose often adapt by substituting mutations in the lacI repressor that cause constitutive …

Background Social defectors may meet diverse cooperators. Genotype-by-genotype
interactions may constrain the ranges of cooperators upon which particular defectors can …

We introduce a simple test to infer mode of selection (STIMS) in metagenomic time series of
evolving asexual populations. STIMS compares the tempo of molecular evolution for a gene …

Cooperation is widespread among microbes. One mechanism proposed to constrain
cheating is antagonistic pleiotropy, wherein mutations that cause defection from …

Social and genomic context may constrain the fates of mutations in cooperation genes.
While some mechanisms limiting cheaters evolve in the presence of cheating, here we ask …

Epistatic interactions can greatly impact evolutionary phenomena, particularly the process of
adaptation. Here, we leverage four parallel experimentally evolved lineages to study the …