 Tuberculosis is an enormous global problem. If you look at statistics of a couple of years ago, roughly 2 million people died of TB. Now it turns out that there is a very close bacterial relative of the human TB bacteria that causes fish tuberculosis. And when you look at the pathology of the disease, it looks very similar to what human TB bacteria cause in humans. In a disease like TB, you've got two players. You've got the bacterium and you've got the host. My dream would be to have a much deeper understanding yet of every trick that the bacterium uses to establish itself in the host and to produce disease. That's a black box. We use the zebrafish as a model organism. A friend of mine calls it the living laboratory. They're so cool. For the first two to three weeks, it's optically transparent. So we can follow the fate of individual cells and individual bacteria, see where they're going, see what they're actually doing. It sounds simple, but its power has been extraordinary. We found completely new ways in which we think that a certain form of resistance to the bacteria develops a form of resistance that is called drug tolerance. And that has turned out to be quite a revelation. It is critically important that our animals be really treated wonderfully. There is no way that we could have made the discoveries that we've made without the fish.