How Ethologists Learned to Respect Animal Minds

Animals think; here's how even the experts came to agree.

Posted Nov 21, 2019

How did the erroneous view that other animals lack an internal mental life get started? It wasn’t merely a consequence of self-serving theology and a reaction to anthropomorphism, but has some legitimate basis in science. Early research by ethologists focused on the role of “releasers,” simple stimuli that are typically present in members of a given species, to which individuals respond automatically and instinctively—nearly always without any indication of insight.

The classic example was the orange spot near the tip of an adult herring gull’s bill. Niko Tinbergen (who shared a Nobel Prize for his ground-breaking research) found that herring gull chicks instinctively pecked at this spot, presented by a parent gull, who then responded—also instinctively—by regurgitating a semi-digested fish meal into the mouth of the hungry chick. Especially noteworthy is that chicks were equally likely to peck at something that at least to the human observer doesn’t look at all like the head of a herring gull, namely a tongue depressor or popsicle stick on which an orange dot has been painted.

Tinbergen also noticed that male stickleback fish, kept in his lab at Oxford, used to rush to the side of their aquarium and display aggressively when mail trucks—painted red in England at the time—drove by. Not coincidentally, male sticklebacks develop bright red chests when in breeding condition, and their cognitive skills are so limited (or more accurately, in this case, bypassed by a simple algorithm) that they take anything moving and bright red as a signal that automatically releases aggressive territorial defense. In my own research, I have taken advantage of a similar releaser among male mountain bluebirds, whose bright blue plumage can be mimicked by a bright blue racket-ball, to the extent that the ball, impaled on a nearby tree, evokes a full repertoire of mountain bluebird display behavior. Such examples are common currency among students of animal behavior.

Further evidence for the cognitive limitations of many animals comes from the existence of “supernormal releasers,” created when researchers take a releaser and enhance or exaggerate it to supernormal proportions, whereupon it evokes a supernormal response, demonstrating once more—often to comical excess—an absence of deep thought (or even shallow thought) among a wide range of animals. A notable example is provided by Pacific oystercatchers, rather debonair looking shorebirds with black and white plumage, and bright orange legs and beak. These crow-sized birds lay eggs that are lightly speckled and appropriate for their mass—a bit smaller than hen’s eggs—which they incubate. 

Take a watermelon, however, and paint it with similar speckling, and the seemingly addle-pated oystercatcher will abandon her own eggs and perch, apparently quite satisfied, albeit looking entirely absurd to a human observer, atop this super-normal releaser (which might weigh 20 times her body mass and could never have been laid by the animal in question), all the while ignoring her own eggs.

Put these observations together, and add the fact that the animals typically studied by the classical ethologists such as Tinbergen and Konrad Lorenz have been insects, fish and birds; sprinkle in scholarly resistance to the anthropomorphizing of non-human animals; and then stir carefully with the intellectual spice of ethologists’ reaction to comparative psychologists' emphasis on animal learning. The conclusion that animals lack complex cognition becomes almost unavoidable. The final coup de grâce came from Occam’s Razor, the scientific principle that natural explanations should not be elaborated unnecessarily—i.e., when in doubt, the simplest, least elaborate explanation, requiring the smallest number of additional assumptions, should be taken as correct.

Occam’s Razor is generally a good rule of thumb. But it is neither sacrosanct, nor so sharp that it cuts through all aspects of reality. There is nothing inherently valid about simplicity; sometimes, the nature of the world is best explained by bafflingly complex laws and patterns. (Just take a look at the equations in a physics textbook, especially a graduate-level treatment.)

While releasers and supernormal releasers are apparent in many animals—especially those with relatively simple brains whose behavior is most efficiently tuned to provide simple reactions to simple stimuli—a healthy reaction to the minimalist perspective on animal behavior has been gaining adherents in recent years. Known as “cognitive ethology” or “evolutionary cognition,” it has effectively broken the long-standing taboo against giving animals their due, acknowledging that for many species, and in a variety of circumstances, animals experience a rich mental world.

The biologist (and PT blogger) Marc Bekoff and primatologist Frans de Waal have recently been especially effective in puncturing the myth of animal mental vacancy, and in the process, giving the lie to the myth that only human beings think. Most influential in this respect was the biologist Donald Griffin; and herein lies an interesting story, not only of science but also the sociology of researchers.

For decades, the study of animal cognition (and a related, even more controversial assertion, animal consciousness) was the third rail of ethological research: touch it and you wouldn’t get a research grant or tenure. Griffin was no starry-eyed animal lover addicted to anecdotes about his pet cat; rather, he was a highly regarded scientist, who, through a series of careful empirical studies had discovered that bats used echolocation (essentially, a form of ultra-high frequency sonar) to avoid obstacles and detect their insect prey. Griffin then shocked the animal behavior establishment when in a series of carefully argued books—notably Animal Minds, Animal Thinking, and The Question of Animal Awareness—he urged his colleagues to take seriously the question of, well, animal minds, animal thinking and the question of animal awareness.

Once a giant like Griffin said it was kosher, a growing number of biologists and psychologists began treading where no self-respecting scientists had previously allowed themselves to go. The results have been overwhelmingly persuasive, such that these days, virtually no scientist publicly doubts the mental life of nonhuman animals.

David P. Barash is professor of psychology emeritus at the University of Washington. Among his recent books is Through a Glass Brightly: using science to see our species as we really are (2018, Oxford University Press).