The genotype–fitness map (that is, the fitness landscape) is a key determinant of evolution,
yet it has mostly been used as a superficial metaphor because we know little about its …

Epistasis occurs when the effect of a mutation depends on its carrier's genetic background.
Despite increasing evidence that epistasis for fitness is common, its role during evolution is …

Microbial consortia exhibit complex functional properties in contexts ranging from soils to
bioreactors to human hosts. Understanding how community composition determines …

Experimental studies of evolution have increased greatly in number in recent years,
stimulated by the growing power of genomic tools. However, organismal fitness remains the …

Genotype–phenotype relationships are notoriously complicated. Idiosyncratic interactions
between specific combinations of mutations occur and are difficult to predict. Yet it is …

The structure of fitness landscapes is critical for understanding adaptive protein evolution.
Previous empirical studies on fitness landscapes were confined to either the neighborhood …

By formalizing the relationship between genotype or phenotype and fitness, fitness
landscapes harbor information on molecular and evolutionary constraints. The shape of the …

Natural selection drives evolving populations up the fitness landscape, the projection from
nucleotide sequence space to organismal reproductive success. While it has long been …

Understanding the pattern of epistasis—the non-independence of mutations—is critical for
relating genotype and phenotype. However, the combinatorial complexity of potential …

Mutations in protein active sites can dramatically improve function. The active site, however,
is densely packed and extremely sensitive to mutations. Therefore, some mutations may …