A collaborative team of scientists led by the University of Massachusetts Amherst recently found that there is no physiological evidence supporting a leading theory—which involves the surface area of fish gills—as to why many fish species are "shrinking" as waters grow warmer due to climate change. Known as the Gill Oxygen Limitation (GOL) theory, it has been proposed as the universal mechanism explaining fish size and has been used in some predictions of future global fisheries yields.