The Clever Hans Phenomenon from an Animal Psychologist's Point of View

Abstract

Swiss zoologist Heini K.P. Hediger (1908–1992), is the second historical figure named in Thomas A. Sebeok’s review of the “three successive twentieth-century iterations of biosemiotics” prior to the one that Sebeok himself initiated. “One of the sundry riddles that mar the gradual coming into view of modern biosemiotics,” writes Sebeok, “is the neglect of Heini Hediger, whose lifelong attempt to understand animals surely marked a milestone in the elucidation of this domain, providing it with a particularly beneficial empirical footing” (2001: 66). Born in Basel, Switzerland on November 30, 1908, Hediger would later recount that his early fascination with animals included, by age six, a self-collected menagerie of “sea anemones, fish, snakes, owls, a fox, an opposum, and a slow loris” (1969: 145). His obsessive attention to the behavior of these animals, and the incessant growth of this menagerie, writes Hediger “was negatively correlated with my success at school” (ibid). Still, it was clear to him that the study of zoology was his life’s passion, and Hediger went on to excel at his studies of zoology, botany, psychology and ethnology at the University of Basel’s Zoological Institute under the tutelage of zoologist and interdisciplinan Adolf Portman (1897–1982) from 1927 to 1932. During this time, Hediger also undertook zoological field work in Morocco, Papau New Guinea, and the Solomon Islands, where he discovered several new species – and even a new genus – of reptiles, this latter being the Melanesian coral snake Parapistocalamus hedigeri. What intrigued him most on these expeditions, however, were the related phenomena of territorial marking and the flight distances involved in the escape behavior in fiddler crabs. Hediger’s 1934 paper on these phenomena, “Zur Biologie und Psychologie der Flucht bei Tieren”, helped pioneer the then newly emerging field of animal ethology (along with his then-unknown colleagues Konrad Lorenz and Nikolass Tinbergen, with whom Hediger maintained an active scientific correspondence for many years, as well as with Jakob von Uexkull, whose