As someone who studies human performance, from time to time I have people ask why scientists will test animals to understand human performance. In most cases, it is because to continue to understand why humans can do what they do (and how we can train them to do ‘it’ better), we have to use models that allow us to do things that we can’t do in humans. For example, my lab has a long-running set of experiments where we are looking at humans’ drive to be active. Much of this drive probably o...