title: Past, present, and future of comparative psychology.
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D001522:Behavior, Animal; D005075:Biological Evolution; D005010:Ethology; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D011587:Psychology, Comparative / Q000266:history*; D012107:Research Design; D014481:United States