Nopcsa's main contribution to paleontology – and hence "paleobiology" – was, that he was one of the first researchers who tried to "put flesh onto bones." At a time when paleontologists were mainly interested in assembling bones, he tried to deduce the physiology and living behavior of the dinosaurs he was studying. Nopcsa was the first to suggest that these archosaurs cared for their young and exhibited complex social behavior, an idea that did not take off until the 1980s. Because he was one of the first people to study the biology of dinosaurs, he is known as the 'father of paleobiology', even though he himself coined the term "paleophysiology" for the study of the evolution of physiology and biology.