The second most intelligent creature living on Earth

Just how intelligent are dolphins?


The following is an excerpt from Are Dolphins Really Smart? by Justin Gregg, and attempts to disprove the myth that dolphins are the second most intelligent creature on Earth.

“The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd; indeed in view of the silliness of the majority of mankind, a widespread belief is more likely to be foolish than sensible.” (Bertrand Russell)

This is the story of a truly remarkable animal. Its bond with humankind goes back many centuries, if not millennia, and it appears in our earliest myths and legends. Recent scientific research has revealed its sophisticated social behavior and remarkable cognitive abilities. With these discoveries, many who once spoke of the undeniable superiority of the human intellect have been humbled into silence. What’s more, this extraordinary creature is only distantly related to humans and other primates, which makes the following six discoveries of its intellectual prowess all the more startling:

(1) They can live in groups numbering in the hundreds and are able to recognize and remember individuals within the group, as well as their place in a complex social hierarchy.

(2) Certain behaviors appear to be learned from other members in the group: a form of social transmission of behavior traditionally seen only in primates, and the first steps toward what scientists now refer to as animal culture.

(3) They have been shown to display signs of empathy — registering increased heart rate and anxious behaviors when watching their friends or family in distress.

(4) When food is found, they will alert members of the group by producing a complex series of vocalizations that vary depending on the kind of food. What’s more, these vocalizations appear to refer to food in a one-to-one correlation — almost like human words.

(5) They produce unique vocalizations that appear to refer to different threats in the environment — these vocalizations are meant to warn the group of approaching danger. Individuals will take evasive action that differs depending on the kind of vocalization they hear.

(6) In experimental conditions, they have been shown to have the ability to anticipate future events, and to exercise self-control — delaying an immediate food reward when they realize that by waiting they may get an even larger food reward. Thus, like humans, they may be able to plan for the future.

This inventory of astonishingly complex cognitive talents belongs not to the dolphin (as one might have expected based on the title of this book), but to the humble domestic chicken. Surprised? If so, you can take some comfort in the fact that some (although not all) of these complex behaviors have also been observed in dolphins. The lesson here, however, is that chickens are not as dim-witted as popular opinion would have us believe. Long-held ideas of animal intelligence are increasingly out of step with the rapid pace with which the vanguard of science penetrates the mysteries of the animal mind.

If Bertrand Russell’s tongue-in-cheek maxim as to the silliness of mankind is as insightful as it is funny, there’s good reason to subject these popular ideas to careful scrutiny.

Popular opinion considers dolphins to be fairly intelligent animals. As we shall see, there is ample scientific evidence to lend support to this idea. But if we’re going to think critically about what it means to be “a fairly intelligent animal,” we’ll need to do three things: firstly, produce a working definition of intelligence; secondly, get to grips with what the scientific literature on dolphin intelligence is (or is not) telling us; and thirdly, put these findings in proper context by examining what is known about the intelligence of other species. We’ll need to ponder the implications of this list of ostensibly complex chicken behavior, and decide what it means that the veined octopus, with a brain smaller than a dolphin’s eyeball, is known to use tools with a sophistication rivalling that of dolphins.

The past few decades have produced many startling discoveries of complex animal behavior scattered throughout the taxa, including in animals previously considered unintelligent. Science continues to challenge our traditional ideas about where individual species should be placed on the continuum of animal intelligence, and whether a continuum of animal intelligence is a useful model to begin with. Dolphins might well be smart, but the idea that they sit atop a pedestal as “the second most intelligent species on the planet” is now passé. Under Ben Goldacre’s banner of “I think you’ll find it’s a bit more complicated than that,” I can safely state that the notion that dolphins are smart and chickens are stupid is at best a gross oversimplification, and at worst completely wrong and thoroughly unhelpful.


Are Dolphins Really Smart?, by Justin Gregg (Oxford University Press, 2013)

Justin Gregg is a research associate with the Dolphin Communication Project, and Co-Editor of the academic journal Aquatic Mammals. He received his doctorate from Trinity College Dublin in 2008, having studied social cognition and the echolocation behavior of wild Indo-Pacific bottlenose dolphins. With an undergraduate background in linguistics, Justin is particularly interested in the study of dolphin communication. He is the author of Are Dolphins Really Smart? (OUP, 2013).

Featured image credit: Dolphin, by Claudia14. Public domain via Pixabay.

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