Adaptive landscapes: Top-down and bottom-up perspectives

Sewall Wright introduced the metaphor of the~adaptive~landscape, a map from genotype to fitness, more than 80 years ago to help describe his view of~adaptive~evolution.~ This metaphor has been immensely popular and has been used in a variety of incarnations.~ However, a systematic study of the genotype-fitness map presents significant problems. The space of possible genotypes is vast, and the mapping is likely dependent on both environment and the composition of genotypes in a population.~ In this talk, I will discuss some of these problems and present experimental strategies for uncovering features of~adaptive~landscapes.~ In particular, I will discuss how population structure can be used as an experimental variable to elucidate~landscape~topography and how a combination of experimental evolution and genetic engineering can reveal important~landscape~features in changing environments.~ I will also present some potential applications of this work to the problem of antibiotic resistance and potential implications for evolutionary rescue in the face of global climate change.~ For some of these topics, the classic notion of the~adaptive~landscape~must itself be adapted; however, I propose that there are fruitful ways to continue to apply this metaphor.