Gene flow, adaptation, and speciation. How does adaptation lead to speciation? Guided by theory, we perform experiments with yeast S. cerevisiae, and focus on the following questions,

• What is the role of gene flow in dictating the speciation process?

• How does the environment dictate the nature of reproductive barriers that arise between populations in allopatry?

Factors dictating adaptation. Adaptation is a consequence of natural selection acting on randomly occurring mutations, and adaptive trajectories depend on GxG GxE interactions. We ask what is the role of
(a) The exact nature of the environment in dictating adaptive and pleiotropic effects.
(Ref -  Adaptive and pleiotropic effects of evolution in synonymous sugar environments,
Resource presentation dictates genetic and phenotypic adaptation in yeast)
(b) The role of genetic interactions in shaping adaptation. (Ref - Variations and predictability of epistasis on an intragenic fitness landscape)

Evolution in public-goods systems. Public goods systems are ubiquitous in ecology. However, the role of the environment and the participating species is not clear in dictating the evolution of different types of interactions, like cooperation, altruism, diversification, etc. We design evolution experiments to study these phenomena in real-time.
(Ref - Increased privatization of a public resource leads to spread of cooperation in a microbial population,
Empirical evidence of resource-dependent evolution of payoff matrices in Saccharomyces cerevisiae populations,
Public good-driven release of heterogeneous resources leads to genotypic diversification of an isogenic yeast population)

How do genes cross a species barrier? Horizontal gene transfer leads to a gene moving to a new intracellular environment (e.g., distinct GC percent, tRNA abundance). Sometimes this leads to the horizontally acquired gene being non-functional in the new host environment. What is the mechanistic basis of this non-functionality, and what is the genetic basis of the process that makes this gene functional in the new host? (Ref - Synonymous and single nucleotide changes facilitate the adaptation of a horizontally transferred gene)