Rokyta Lab Research Summary

Research in the Rokyta lab is currently focused on developing robust and empirically verified models of adaptive evolution. We construct models that predict the statistical properties of adapting populations and then test both model predictions and assumptions using a viral system. The viruses we use are bacteriophages that infect Escherichia coli and readily adapt to controlled conditions in the lab, allowing repeated observation of the evolutionary process. We also use these viruses to investigate basic properties of organisms that affect the way they evolve, including epistatic interactions and the genotype-phenotype-fitness relationship. We have recently begun to apply what we have learned from laboratory evolution to studying how adaptation occurs in a geographic context for more complex organisms. We are studying the evolution of venom proteins from a number of snake species in the Southeastern United States.

Adaptation Theory

The Rokyta lab develops predictive models of adaptation based on two main assumptions: adaptation happens in the space of DNA sequences and beneficial mutations are rare. These models are formulated in the context of the evolution of a single gene or small genome and are intended to make robust predictions of patterns in the genetics of adaptation. More adaptation theory.

Viral Evolution

The Rokyta lab studies the bacteriophages of the family Microviridae in both natural and laboratory settings. Because of their short generation times, bacteriophages can adapt to new conditions in the laboratory over the course of days. We can therefore observe and characterize evolution as it happens in the lab under controlled and repeatable conditions. More laboratory evolution. This type of short-term evolutionary data is nicely complemented by studies of longer-term evolution in natural settings. We can sample an almost limitless supply of naturally occurring viral genotypes and use statistical genetics approaches to elucidate their evolutionary history. More environmental evolution.

Snake Venom Evolution

The Rokyta lab is currently developing genomic resources for a number of venomous snake species and using them to study adaptive evolution in snake populations. Venoms are much like viruses: a set of proteins designed to procure resources for reproduction. These proteins evolve remarkably quickly under strong positive selection and have relatively simple genotype-phenotype-fitness relationships. They are therefore ideal for studying adaptive evolution in natural populations. More snake venom evolution.