Key arguments, based on the original suggestion of Alister Hardy, were developed and presented from 1972 by Elaine Morgan.[1] In later years, other contributors have further developed the aquatic ideas, some of which substantially differ from the original "aquatic ape" of Hardy et Morgan. The term "waterside hypotheses of human evolution" has been coined by AAH-proponent Algis Kuliukas to collectively represent this diversity, of which AAH is only one such hypothesis. Most traits perceived as aquatic are physiological and biochemical, while few are behavioral (ethological). The time frame for the origin and possible termination of such an aquatic existence also differs between proponents, although the same time frame as anthropological consensus is generally followed. In most cases, this aquaticism is perceived as having been instigated by selective pressure around the split of the last common ancestor between humans and chimpanzees.[19]