Is evolution predictable? What are the mechanisms that allow different fish to respond to the same environmental challenge in slightly different ways? When the same jaw bones and muscles change to produce the same feeding behaviour, are the morphologies of these fish that evolved independently from one another modified in an identical way? What is the genetic basis for this kind of convergence? These are some of the questions that Dr. C. Darrin Hulsey and Professor Axel Meyer from the Department of Biology at the University of Konstanz and their international colleagues from the University of California in Los Angeles (USA), Tel Aviv University and the Inter-University Institute for Marine Sciences in Eilat (Israel) are trying to answer.