Are Dolphins Not as Smart as We Thought?

By Guest Blogger | October 4, 2013 12:02 pm

By Erik Vance

dolphins painting skills

In Douglas Adams’s hilarious classic, Hitchhiker’s Guide to the Galaxy, there are several animals said to be cleverer than humans. One – for the sake of irony – was the common lab mouse. The other was a creature that knew about the intergalactic bulldozers that eventually vaporized the planet and tried to warn us of the impending doom:

The last ever dolphin message was misinterpreted as a surprisingly sophisticated attempt to do a double-backwards-somersault through a hoop whilst whistling the ‘Star Spangled Banner’, but in fact the message was this: So long and thanks for all the fish.

It’s a fun punchline but it also reflects a long-held sentiment: that dolphins possess an unusual level of intelligence that sets them apart from the rest of the animal kingdom. In the popular consciousness it’s taken as a given that dolphins are highly intelligent, have complex behavior, and possess some kind of proto-language ability. However in recent months and years, a sort of backlash – or at least a re-alignment – has been fomenting on the periphery of animal behavior research.

Dolphin Exceptionalism

Dolphins’ revered status among animals really began with John Lilly, a 1960’s era dolphin researcher and psychotropic drug enthusiast who was the first to popularize the idea that dolphins are intelligent, later suggesting that they were even more so than humans.

Lilly was eventually mostly discredited and didn’t contribute much to the science of dolphin cognition after 1970. Yet despite mainstream scientists’ efforts to distance themselves from his more bizarre ideas (that dolphins were spiritually enlightened) and even his tempered ones (that dolphins communicated in holographic images), his name seems inexorably linked to dolphin intelligence work.

“He is, as I am sure most dolphin scientists will agree, the father of the study of dolphin intelligence,” writes Justin Gregg in a book, due out in November, titled Are Dolphins Really Smart?

Since Lilly’s research, dolphins have been shown to understand signals given by television screen, distinguish different parts of their bodies, recognize their own images in mirrors, and have highly complex whistle repertoires that include some that seem to refer to specific animals (called signature whistles).

But some of these ideas have been lately called into doubt. Gregg’s book is the most recent embodiment of the tug-of-war over neuroanatomy, behavior and communication – between the idea that dolphins are special and the idea that they’re on par with lots of other creatures.

Why the Big Brains

The diminution of dolphins thus far has taken two main tacks: anatomical and behavioral.

In the first category is a recent journal paper by anatomist Paul Manger, reiterating his long-held position that the large dolphin brain has nothing to do with intelligence.

Manger, an iconoclastic researcher with the University of the Witwatersrand in South Africa, has previously asserted that the dolphin’s large brain more likely evolved to help the animal retain heat than to carry out cognitive functions. That 2006 paper was widely criticized by the dolphin research community.

This new paper (also written by Manger alone) takes a critical eye towards brain anatomy, the archeological record, and oft-cited behavioral studies, concluding that cetaceans are no more intelligent than other vertebrates and that their large brains may have evolved for another purpose. Unlike in the previous version, he picks at many of the behavioral observations, such as the mirror recognition test profiled in the September 2011 issue of Discover, saying that they are either incomplete, incorrect, or go beyond the data.

Lori Marino, a neuroanatomist at Emory University and advocate for large-brained intelligence, says another multi-author rebuttal is now in the works.

Get Smart

The other argument, that dolphins behaviorally aren’t as impressive as has been claimed, is made by Gregg.  A professional dolphin researcher (and voice-over actor for animated films), Gregg says he respects dolphin “accomplishments” in cognition research but feels the public and certain researchers have elevated them to a level of cognition beyond what the data suggests, and that other animals display many equally impressive traits.

In his book, Gregg cites experts who call into doubt the value of the mirror-self-recognition test, an exercise thought to indicate some degree of self-consciousness. Gregg notes that octopuses and pigeons can learn to behave similarly to dolphins when given a mirror.

In addition, Gregg argues that communication has been especially oversold in dolphins. While certainly their whistles and clicks are a complicated form of audio signaling, he cautions that they show none of the hallmarks of human language (such as encompassing limitless concepts or freedom from emotion).

He also mentions attempts to apply information theory – a branch of mathematics – to the information contained in dolphin whistles, citing others who question whether information theory is even appropriate for animal communication.

Gregg emphasizes that dolphins certainly display many impressive cognitive abilities – but that many other animals do as well. However his animals of choice aren’t altogether flattering: in the first chapter he insinuates that by many metrics chickens are as cognitively capable as dolphins. And later, conceding that dolphins can understand television screens, he writes: “Jumping spiders, with their eight eyes and brains so big for their body size that they spill over into their legs, seem equally as skilled.”

Gaining Traction?

It’s important to note that researchers like Manger are in the small minority among researchers who have examined dolphin cognition. Furthermore, even Gregg tries to distance himself from the idea that dolphins are mediocre, rather saying that other animals are cleverer than we thought.

But though it’s unpopular, perhaps the dull (or at least unexceptional) dolphin theory at least deserves consideration. Even Gordon Gallup, the behavioral neuroscientist who first used mirrors to evaluate whether primates are self-aware, expresses doubts about the dolphin’s capacity for this humanlike ability.

“The evidence for mirror self recognition in dolphins is tenuous. It’s not substantive,” Gallup told me in 2011. “[Videos taken during the experiment] are far less compelling in my opinion. They’re suggestive but hardly definitive.”

Arguments against dolphin exceptionalism boil down to three basic ideas. One, as Manger seems to press, is that dolphins simply aren’t any smarter than any other animal. Two, it’s difficult to compare any one species against another. And three, there simply isn’t enough good research on the topic to make solid conclusions.

In Are Dolphins Really Smart? Gregg himself isn’t able to do much to answer his own question beyond “Yes, they’re pretty smart.” They cannot teleport or do high-level mathematics, but we knew that. And don’t plan on getting any kind of warning before the world is obliterated by intergalactic bulldozers.

Erik Vance is a science writer based in Mexico City. He writes about the environment, brain science, and occasionally hamster sex. Read more of his writing at the Last Word on Nothing.

Image by Elena Larina / Shutterstock

CATEGORIZED UNDER: Living World, Top Posts
  • Rus Archer

    how would we rate buddhist monks if we determined intelligence based on activity?

    • Robert Ford

      yeah, you see a lot of Nobel winning buddhist monks.

      • Kiel Fisher

        I think Ajahn Brahm, buddhist monk of the Western Australia Buddhist Society and prolific YouTube speaker, is far more deserving of the Nobel (Peace, since you didn’t specify) prize than, say, POTUS Barack Obama. I don’t think you should be insulting the general intelligence of monks, anyway, but you could at least mention a proper scientific or technological award, like the Turing Award, or the Fields Medal.

        • m12345

          The nobel peace prize has NOTHING to do with the Nobel science prizes, different people. One is for scientific advancements subject to extensive peer review, the other the peace prize is not scientific, not peer reviewed to any world standards and is quite frankly an opinion with as much traction as a 2 year getting a lollipop for being quiet for 2 minutes.

          • Rus Archer

            the point is
            MAYBE intelligence produces different behavior than expected
            the logic goes backwards here

          • Cinnabomber


    • WAYNE

      but Mr. Archer you have not specified what sect of buddhism these monks are activating themselves through which brings us to that “aha!” moment in questioning.

      • Rus Archer

        what matter?
        a roomful of people doing sitting meditation for hours and days and weeks on end
        less intelligent than we thought?

  • tfosorcim


    Nooooo…it’s that dolphins are not as smart as we thought WE were.


  • Psyclic

    Do other animals name members of their family/clan? Recent research indicates dolphins do this; is this another false reading of the data? Dolphins have been seen to pass on training/learned informationm to other dolphins. While this has been largely annecdotal, and Nick Bostrom thinks it false, significant observations appear likely.
    Are they MORE intelligent than humans? Well they don’t have serial killers, or organized warfare, or deaths by guns or cars.

    • Stannous Flouride

      No guns but that is more due to a lack of opposable thumbs than lack of murderous intent.

      Dolphins are dicks!

      Pods of young males will kidnap females and trap them underwater until they acquiesce and submit. They will hold them for months as group concubines.

      They regularly kill the babies of other dolphins, much as lions do, to force females in to estrus so they can be mated.

      The seem to kill porpoises for fun. Much smaller porpoises are no threat, they don’t even eat the same prey. But gangs of bottlenose dolphins will ram their bellies until they drown and then toss their corpses back and forth in the air.

      And though their are stories of dolphins aiding and saving humans dating far back in history there are many recent reports of dolphins attacking humans.
      Not just those kept as performing slaves in wild animal parks (which might be understandable) but in the wild as well.
      A search of Youtube brings up numerous examples of aggressive dolphins harassing humans.

      They have cute smiles and are charming but so do most psychopaths.

      • Psyclic

        SnF2 – The major premise of the article and my response was regarding the INTELLIGENCE of dolphins. The last line was a throw-away – “More Intelligent” is a terribly culturally charged phrase.The annecdotal references to rape, infanticide, killing for fun, and holding sex slaves are interesting, and no doubt have some basis in reality, but their portrayal is anthropomorphically vituperative and not dispassionate as the anecdotal stories demonstrating intelligence.
        But it does open up an additional line of investigation.

        • JennySueNY

          So is the entire notion and study of intelligence.

    • JennySueNY

      Dogs and horses also pass on training/learned information.

      • Marky Mark

        Yeah, I taught my dog how to roll over, and she went on to teach it to her puppies, who also taught it to all their puppies. I snap my fingers, and there’s a room of 50 dogs all rolling over, when I only ever taught one of them the trick.

        It makes training dogs and horses so easy, you just show one what to do and they’ll teach the rest for you!

        Or that isn’t true and you’re an idiot.

        Dolphins pass on things that they’ve been taught. Dogs and horses do not.

        • Rivka

          Dogs do pass on learned information. Many owners have noticed that puppies do often learn to be housebroken from other dogs, learn to come when called based on the actions of other dog, do learn actual trained commands, as well as more natural behaviors such as hunting techniques.
          Perhaps you’ve never seen this happen first hand. But you’re relying only on the word of others as far as dolphins are concerned-the word of others has equal weight when it comes to dogs.

  • MadVirus

    I would love to see what happens if you’d put a large touch screen in their aquarium, with a basic user interface (erase, changing colour and brush size). Eventually the most enthusiastic dolphins will continue using it and who knows what they’ll draw! You can add more features as they improve.

    • JennySueNY

      That will only work if they perceive colors and shapes as we do. Who knows?

    • Ygorbla

      My guess is that they would probably get electrocuted on account of the fact that you just tossed a touch screen into an aquarium.

    • Ivana Mladenova

      Well, maybe…except that they are colorblind or monochromats – they have only one type of cone that percieves very weakly blue colors…every marine mammal is like that

  • Marcus Tullius

    Claiming that dolphins aren’t any smarter than other animals or that its impossible to make these sorts of comparisons is inane.

    First of all, the two statements conflict with one another.

    Secondly, nobody would seriously deny that a human is smarter than a dog which is smarter than a jellyfish.

    At the end of the day, the best evidence is that dolphins can be classed along with primates, elephants, parrots, crows, etc. as some of the most intelligent animals out there.

    • JennySueNY

      They are saying that the best evidence is really not very good evidence.

      • Psyclic

        No, “they” are repeating the minority science opinions of Justin Gregg.

        • ebolaoutkast

          Gregg is brilliant. The fact that his opinion is in the minority does not mean otherwise.

  • JennySueNY

    The basic question is are they self aware and able to contemplate pain. Are they aware of danger or do they just respond instinctively to threat. Are we projecting our feelings on to them?

    • Psyclic

      INTELLIGENCE! Without projection – No bondage/rape/kidnap/kill-for-fun – these are all HUMAN DEFINED/CULTURALLY DEFINED behaviors. Self-aware? We don’t even know what that means for Humans! Do we respond instinctively? Do WE have free-will – you bring a lot of baggage here.
      I’m not advocating marriage to dolphins – only acknowledging intelligence is a multifaceted behavior, and one that is well demonstrated by dolphins.
      As an aside, it seems noteworthy that many of the Discover articles tend to draw emotional comments – it would seem that they are trolling with chum.

      • The Network Company

        You are attributing a level of kindness to dolphons that may not be well earned. Like humans there are bad dolphins that commit murder, abandon their children prematurely, rape, and do other things that we might look down on. regular animal behavior.

        • Psyclic

          It’s not clear where your argument is coming from – I am not attributing ‘kindness’ to dolphins, any more than ‘understanding’ to the commenters here – only intelligence. But that may be overstating the case.

  • The Network Company

    Crappy article quotes the opinion of not real or respectable scientists to make a point that most real scientists would disagree with. Dolphins appear able to execute and remember human instructions more than any other species ergo their use in very sophisticated and synchronized swimming shows. It has been shown that they are able to recognize and respond to more visual symbols than chimps and they are very definitely the second most intelligent creatures on earth.

    • Rivka

      The only point it’s making is that dolphins don’t have human level intelligence. Which is a point that I believe no real scientist would actually disagree with.

  • Amelie ஐ..•.¸¸•. « Meel »

    Ohhh!!! The donphins are intelligent and fascinating creatures, extremely playful and social. :3

  • Jonea

    “Everybody is a genus. But if you judge a fish on its ability to climb a tree, it will live its whole life believing it is stupid.”


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