In this issue

Comparative Psychology and Ethology

Comparative Psychology is a sub-discipline of psychology and ethology of biology
By Gary Greenberg, PhD
(To appear in the forthcoming Encyclopedia of the Sciences of Learning, Springer)


Comparative Psychology and Ethology are both sciences which study animal behavior, typically non-human behavior, though both have often studied humans. Comparative Psychology is a sub-discipline of psychology and ethology of biology. Both can trace their roots to the late 19th century. Depending on which history one reads the first comparative psychologist was Pierre Flourens, a protégé of Baron Cuvier or George John Romanes, a friend and student of Charles Darwin. Flourens' book title represented the first use of the term, Comparative Psychology (Psychologie Comparée, 1864) and pre-dated Romanes' Animal Intelligence (1882). Both proposed a science which would compare animal and human behavior, Romanes postulating the existence of a gradient of mental processes and intelligence from the simplest animals to man - the comparative approach much in use today. Romanes strengthened his proposal by a vast collection of anecdotal accounts of clever behavior in dozens of animal species. Though perhaps best known today for the fallacies of his anecdotal method and for his easy assignment of human mental faculties to animals--anthropomorphism--Romanes nevertheless succeeded in establishing his idea of a gradient of mental processes across the ani-mal kingdom as a basic premise of early comparative psychology. Ethology too has a mixed parentage. Isidore Geoffroy-Saint-Hillaire first used the term in 1859, though Oskar Heinroth, a late 19th century German biologist was one of the first to apply the methods of comparative morphology to animal behavior; he is thus considered to be one of the founders of ethology.

Both disciplines had many adherents in the early and middle parts of 20th century: Comparative Psychology in the United States under the influence of the learning psychologists (e.g., Ivan Pavlov, Edward Thorndike), the behaviorists (e.g., Zing-Yang Kuo, John Watson, B. F. Skinner), and the epigeneticists (e.g., T. C. Schneirla, Daniel Lehrman, Ethel Tobach, Gilbert Gottlieb); while Ethology became firmly established after WWII in Europe under the influence of biologists such as William Thorpe, Nikko Tinbergen, and Konrad Lorenz. The latter two, in fact, were awarded the Nobel Prize in medicine (there is no separate prize for behavioral research) in 1972 for their animal behavior studies (they shared this prize with Karl von Frisch, an early 20th century biologist).

Theoretical Background

Given the biological roots of both comparative psychology and ethology, evolution was seen to play an important role in behavioral origins by both disciplines, though in different ways. Comparative psychology, strongly influenced by early 20th century Functionalists (e.g., William James, John Dewey), believed behavior allowed organisms to adapt to their environments (i.e., Darwinism); behavior itself was not an evolved phenomenon, though the organism was. Thus, as organisms changed through evolution, new or different behavioral potentials arose. Ethologists, on the other hand, understood behavior itself to be an evolved process, the route being genes--instincts, or inherited behaviors. In later years this one-way route, from genes to behavior, became to be known as the Central Dogma of Molecular Biology. Additionally, while comparative psychology tended to engage primarily in laboratory research, ethology emphasized the significance and importance of studying behavior outside the laboratory, in the natural settings.

These two fundamentally different approaches to the study of behavior lead to a serious intellectual and theoretical ―war around the 1950s. Ethology advocated the position that behavior was a biological phenomenon, determined, and not merely influenced by the organism's genotype; much animal behavior was thus believed to be in-stinctive. Indeed, Lorenz, whose mentor was Oskar Heniroth, and Tinbergen spelled out the full meaning of what instinctive behavior was. The clearest statement of this is found in Tinbergen's book, The Study of Instinct (1951), Comparative psychologists, on the other hand, tended to take an epigenetic approach, stressing the importance of development, experience, and other psychological proc-esses. The differences were summarized in an important paper by Daniel Lehrman (1953), which today still represents one of the best critiques of instinct theory. While healthy, the ensuing debates settled little. It was an important 1966 book by Robert Hinde (Animal behaviour: A synthesis of ethology and comparative psychology) that seemed to resolve the differences between these two opposing views. Indeed, a later 1981 book by the ethologist S. A. Barnett (Modern ethology: The science of animal behavior) was able to discuss the discipline without resorting to instinct explanations.

Important Scientific Research and Open Questions

The two disciplines historically sparred over the nature-nurture issue: Was behavior a biological or a psychological phenomenon? Endless debates over this issue have yet to see it formally resolved. Contemporary reports of the discovery of a gene for a behavior are routinely retracted following failures to replicate such findings - but the search continues. This is as true in psychology as it is in biology, though many in both camps understand behavior to be a biopsychosocial phenomenon. The significance of both psychological and biological development, long ignored, is now seen to be crucial to a full understanding of behavioral origins. And, though studied now for well over 100 years, there are still new developments to be found in the area of learning.

Current Status

While Comparative Psychology grew in America, ethol-ogy remained somewhat stagnant in Europe. Many still identi-fied with the discipline, though it was clear that they had abandoned the hard nosed biological determinism of the classical ethologists. Beginning in 1944 with the initiation of the Ameri-can Psychological Association's divisional structure, comparative psychology had a home in Division 6, Physiological Psychology and Comparative Psychology. In the 1990s, in an effort to attract new members, the division entered into discussion of a name change - the important point for the present discussion was the retention of ―comparative psychology in the new name adopted at the 1995 APA meeting, Behavioral Neuroscience and Comparative Psychology. While membership in Division 6 was falling, Comparative Psychology as a field of study remained healthy as illustrated by the appearance of several comparative psychology societies in the clos-ing years of the 20th century: The Southwestern Comparative Psychology Association (founded in 1983 by Michael Domjan, Del Thiessen, Steve Davis and Gary Greenberg); the Comparative Cognition Society (founded in 1994 by Ron Weisman, Mark Bouton, Marcia Spetch and Ed Wasserman; and the International Society for Comparative Psychology (founded in 1983 by Ethel Tobach and Gary Greenberg). An even earlier group, the International Society for Developmental Psychobiology, was founded in 1967 by George Collier, Norman Spear, Bryon Campbell, John Paul Scott and others. The an-nual and biennial meetings of these societies attract animal behavior researchers from several disciplines across the globe; their membership is also international. There are, of course, several other such societies in countries around the world.

The picture was not so rosy for ethology which seemed to languish in the same period. This was likely because,―The simple truth is that ethology never did deliver as a science of comparative behavior...(Plotkin, 2004, p. 105). Indeed, in 1989 ethology was declared...dead, or at least senescent. That is, if you think of ethology in the narrow sense – the study of animal behavior as elaborated by Konrad Lorenz, Nikolas Tinbergen, and Karl von Frisch. It has been quiescent for some time. No exciting ideas were emerging, and data gathering on key issues had lost its direction... [Barlow, 1989, p. 2].

However, the biological study of animal behavior has thrived well into the 21st century. Ethology was reborn in the early 1970s as a new science, that of Sociobiology (Wilson 1975), the goal of which was to biologicize the social sciences. But this blatant attempt at understanding animal and human behavior as a purely biological phenomenon was met with scathing criticism (Hull, 1988; Lustig, Richards & Ruse, 2004) from numerous quarters. The main point of contention centered around the continuing nature/nurture issue and the question of whether behavior, especially human behavior, was the result of genetic and biological determinism. To many opponents of sociobiology, psychology was not a biological science at all, but a uniquely psychological science (e.g., Greenberg, 2007).

The intellectual sparks flew for years, well into the end of the 20th century which witnessed the appearance of a still new iteration of ethology, Evolutionary Psychology. This approach focuses primarily on human behavior and posited that we owe our universal nature to evolutionary adaptations faced by our Pleistocene ancestors that we have inherited in our genomes. A good source for reviewing the tenets and the research conducted in this field is The Handbook of evolutionary psychology (Buss, 2005). With evolutionary psychology, instincts are once again in vogue. As with ethology and sociobiology, evolutionary psychology is not without its critics (e.g, Honycutt & Lickliter, 2003). It is not the application of evolution to behavior that is at question, but the manner in which it is understood to apply to behavioral origins. Evolutionary Psychology, though seen by many to be seriously flawed, is a rather popular orientation in the contemporary behavioral sciences. After all, what serious scientist in 2010 can object to the significance of evolution to psychology?

There has also been new life breathed into ethology and sociobiology. The sociobiological idea of the genetic basis of human altruism has recently been somewhat retracted by one of its earliest proponents, E. O. Wilson. While this is comforting news to many non-reductionistic comparative psychologists and other animal behaviorists, it doesn't sit well with all students of behavior (Marshall, 2010) attesting to the staying power of the classical ideas of ethology. In a recent analysis Salzen (2010) makes a case for interpreting the ideas of ethology in modern neuroscientific terms. There is in fact a discipline known as―Neuroethology,‖ which describes animal behavior in terms of how the nervous system works. As a comparative psychologist, I take comfort in the staying power of my discipline. Its history has been long, though not nearly as tumultuous as that of ethology.


  • Barlow, G.W. (1989). Has sociobiology killed ethology or revitalized it? In P. P. G. Bateson and P. H. Klopfer (Eds). Perspectives in ethology. Volume 8. Whither ethology? (pp. 1-45). New York: Plenum Press.

  • Buss, D. M. (Ed.) (2005). The handbook of evolutionary psychology. Hoboken, NJ: John Wiley.

  • Greenberg, G. (2007). Why psychology is not a biological science: Gilbert Gottlieb and probabilistic epigenesis. European Journal of Developmental Science, 1, 111-121. Hull, D. (1988). Science as a process. Chicago: University of Chicago Press.

  • Lehrman, D. S. (1953). A critique of Konrad Lorenz's theory of instinct. Quarterly Review of Biology, 28, 337-363.

  • Lickliter, R. & Honeycutt, H. (2003). Developmental dynamics: toward a biologically plausible evolutionary psychology. Psychological Bulletin, 129, 819-835.

  • Lustig, A., Richards, R. J. & Ruse, M. (Eds.) (2004). Darwinian heresies. Cambridge, UK: Cambridge University Press.

  • Marshall. M. (2010). Sparks fly over origin of altruism. New Scientist, No. 2780, October 2, 8-9.

  • Salzen, E. (2010). Whatever happened to ethology? The case for the fixed action pattern in psychology. History and Philosophy of Psychology, 12

  • Tinbergen, N. (1951). The study of instinct. Oxford, UK: Oxford University Press.

  • Wilson, E. O. (1975). Sociobiology: The new synthesis. Cambridge, MA: Harvard University Press.

The content I just read: