During his studies of Lake Geneva, Swiss physician François-Alphonse Forel (1841–1912) established many of the ideas behind the study of limnology and is called the father of limnology. In general, limnology is the study of freshwater inland ecosystems— especially lakes, ponds, and streams—and includes the chemistry, physics, geology, and biology of these bodies of water. These ecosystems are more fragile than ocean environments since they are subject to greater extremes in temperature (because they are much shallower).