There are countless really worthwhile ways to use evolutionary computation (EC) in molecular biology. The chief advantage of EC is that it can find solutions to problems that are too complicated, too nonlinear, etc., to solve by more direct methods. I've used genetic algorithms to evolve models, to find patterns in data, to design optical systems, you name it; and almost always a GA finds solutions I'd never find on my own. Sometimes it's a challenge to find a representation for the solution space that fits the problem well, or to find recombination/mutation operators that work well, but that's where human insight is important. Bottom line: if you can list some problems that fascinate you (or better, fascinate both you and your supervisor), I'd be happy to give you some concrete suggestions.