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Peer Pressure Forced Whales and Dolphins To Evolve Big Brains Like Humans, Says Study (qz.com)

Posted by BeauHD on from the pressures-of-society dept.

An anonymous reader quotes a report from Quartz: The human brain has evolved and expanded over millennia to accommodate our ever-more-complex needs and those of our societies. This process is known as "encephalization" and has given us the big brain we need to communicate, cooperate, reach consensus, empathize, and socialize. The same is true for cetaceans, like whales and dolphins, it seems. These sea creatures also grew big brains in order to better live in societies, according to a study published on Oct. 16 in Nature Ecology & Evolution. According to Michael Muthukrishna, an economic psychologist at the London School of Economics and co-author of the study, the researchers used two related theories, the Social-Brain Hypothesis and the Cultural-Brain Hypothesis, to make predictions about various relationships between brain size, societal organization, and the breadth of behaviors the cetaceans would display. Then they tested these predictions by creating and evaluating a comprehensive database of cetacean brain size, social structures, and cultural behaviors across species using data from prior studies on 90 types of whales and dolphins.

The study found that cetaceans had complex alliances and communications, played and worked together for mutual benefit, and could even work with other species, like humans. Some also have individual signifiers, sounds that set them apart from others, and can mimic the sounds of others. In addition, it found that brain size predicted the breadth of social and cultural behaviors of these marine creatures (though ecological factors, like prey diversity and latitudinal range, also played a role). The researchers concluded there was a tie between cetacean encephalization, social structure, and group size.

21 of 99 comments (clear)

  1. However, by the time you get as social as insects by Anonymous Coward · · Score: 2, Interesting

    The size of the brain doesn't seem to matter so much anymore.

    I see some logic vs Lysenkoism at play here..

  2. Dolphins? by mentil · · Score: 5, Interesting

    My understanding is that dolphins' large brains are mostly glial cells, which are there to keep their brains warm, rather than actual neurons. That's why their brains are so large yet they're only about as intelligent as dogs. Correlations made with dolphin brain size may not end up being very meaningful.

    --
    Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
    1. Re:Dolphins? by lucm · · Score: 3, Funny

      Did you read the Wikipedia article you posted?

      When markers for different types of cells were analyzed, Einstein's brain was discovered to contain significantly more glia than normal brains in the left angular gyrus, an area thought to be responsible for mathematical processing and language.

      So I guess we're fucked if a dolphin gets access to matlab or excel.

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      lucm, indeed.
    2. Re:Dolphins? by Hognoxious · · Score: 5, Funny

      I can't use Excel (post 2003). Perhaps the ribbon interface is designed for use with flippers?

      --
      Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    3. Re:Dolphins? by Solandri · · Score: 3, Funny

      On the Internet, nobody knows you're a dolphin.

    4. Re:Dolphins? by Immerman · · Score: 2

      Insect brains are indeed miracles of scaling and situational reuse.

      Primates have our own interesting mutation on that front: Normally cell size scales with body size - an elephant's cells are far larger than a mouse's, including it's neurons. So brain-to-body size ratio provides a reasonable first-order approximation of intelligence across species.

      Primates though have evolved roughly constant-size neurons, so that large primates have far more neurons than small ones, even when the brain-to-body size ratio is the same. It's only the size of the brain itself that matters for determining potential intelligence. And humans are about as intelligent as one would expect a primate to be based on our brain size.

      Of course that also means that brain-to-body size ratios are utterly useless for comparing intelligence between primates and other species.

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      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    5. Re:Dolphins? by 140Mandak262Jamuna · · Score: 2

      I saw a documentary that showed fires, fire engines, crab shacks, highways and even cars, all under water, all operating seemingly normally. They kept interviewing this citizen named Mr Robert Pants, also known as Spongebob.

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      sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
  3. It Makes Perfect Sense by careysub · · Score: 5, Interesting

    It is clear that high intelligence is not necessary for successful survival, there is no general trend toward progressively evolving high intelligence in any lineage on land but the Hominidae (and it stalled among all the branches of the Great Apes but one). Curiously modern humans 80,000 years ago went through a near extinction event, with the world population dropping to a few thousand individuals, intelligence equivalent to our own did not give them a huge survival advantage at that time.

    But success in a society creates an intelligence arms race. More powerful brains processing social information give an edge in dominating reproduction opportunity through most of evolutionary history. (Debates about whether perhaps the opposite is true at this moment in history I leave aside.)

    --
    Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
    1. Re:It Makes Perfect Sense by Applehu+Akbar · · Score: 2

      You're using environmental activist thinking.

      Intelligence is not needed for your species to "survive" if what you mean by that is existing in vast numbers over long periods of time. But show me the cockroaches with the social structure and self-awareness it would take to figure out its place on the planet and in the solar system, learn that a large asteroid is a hundred years away from destroying all life on Earth, and use that time to find out how to deflect it.

      THAT's how I would define survival.

    2. Re:It Makes Perfect Sense by Solandri · · Score: 3, Informative

      I test nearly autistic, so I had to figure out a lot of the complex rules of social interaction, instead of it being "obvious" like I guess it is to most people.

      As an example, my sister gave me a birthday present which I didn't really need. I thanked her (learned that rule pretty early), but told her I didn't really need it. She knows about my social handicap, so explained to me that when you receive a gift, you're supposed to politely accept it whether or not you really want it.

      Some years later, a friend gave me a gift which I didn't really need. But remembering what my sister said, I thanked her, politely accepted the gift, and tucked it away in the trunk of my car. Where it sat because, well, I didn't really need it. A few months later the friend saw the gift in the trunk of my car and was livid and upset. She bawled about it to a mutual friend, who came and talked with me about it. The mutual friend said I should've just declined the gift if I didn't want it. I explained what my sister had taught me, and she took a deep breath, and said "yes that's true, but not in this situation."

      That day I learned that the rule my sister taught me has an exception. If someone gives you a gift because they like you, accepting it is a sign of being open to reciprocating. And if you're not interested in the person, you're supposed to politely decline the gift as a signal that you're not interested. (Though I'm still a bit unclear how you're supposed to know that the gift is a "like" gift when the person doesn't actually say so when they give it to you.)

      Social norms are full of these rules, exceptions to the rules, exceptions to exceptions, exceptions to exceptions to exceptions, etc. It takes quite a bit of brainpower to figure all this out subconsciously so that it's "obvious" without having to learn it the way I have to.

      And to point out the elephant in the room, there's another behavior which demands social conformity and also has these complex rules and exceptions, thus requiring a bigger brain. Language.

    3. Re:It Makes Perfect Sense by swillden · · Score: 2

      You're using environmental activist thinking.

      I'm not sure what that means. But you're using a fundamental misunderstanding of evolution.

      Intelligence is not needed for your species to "survive" if what you mean by that is existing in vast numbers over long periods of time.

      First, evolution doesn't favor species survival, or individual survival. It favors genetic survival, meaning the survival and replication of a genotype over competing genotypes. In many cases, the best genotype survival adaptations are adaptations that favor the survival or growth of the species, or the individual, but that's a side effect -- and doesn't always happen. Sometimes the adaptation that enables one genotype to out-compete its rivals is actually bad for the species or the individual.

      But show me the cockroaches with the social structure and self-awareness it would take to figure out its place on the planet and in the solar system, learn that a large asteroid is a hundred years away from destroying all life on Earth, and use that time to find out how to deflect it.

      This is very twisted reasoning. The genetic adaptations that led to our large brains were clearly not selecting for ability with astronomy. The most plausible explanation yet presented is that we developed our ability to think about hypotheticals (the core ability that makes science possible) because individuals who could do that were better able to think about the perspectives of their human rivals, and therefore able to outcompete them for mates and resources. That is, we developed big brains not to ensure the survival of our species, but to be better at kicking the shit out of our human opponents (note that that statement actually reverses the true causality, but it's still a useful way to think about it). And we certainly didn't do it in response to evolutionary pressure from planet-sterilizing asteroids.

      THAT's how I would define survival.

      You and Humpty Dumpty.

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    4. Re:It Makes Perfect Sense by Locke2005 · · Score: 2

      To put it slightly differently, for social animals, evolution is driven by the survival of tribes or packs, not the survival of individuals. That's why wolf packs do just fine with only the alphas breeding, and why evolution hasn't eliminated homosexuality.

      --
      I've abandoned my search for truth; now I'm just looking for some useful delusions.
  4. Splain that! by Tablizer · · Score: 2, Insightful

    I have a relatively big brain, but I'm socially clueless.

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    Table-ized A.I.
  5. Facebook addicts? by OYAHHH · · Score: 4, Funny

    Could have sworn I saw a humpback whale staring for hours at an IPhone the other day.

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    Caution: Contents under pressure
    1. Re:Facebook addicts? by Anonymous Coward · · Score: 3, Funny

      Thats not a very nice way to refer to your mother.

  6. size isn't everything by swell · · Score: 2

    If they keep getting smarter they may become as smart as octopuses. Brain size isn't everything. Until recently, the largest human brain ever measured was that of an idiot. Albert Einstein's brain reportedly weighed slightly below average at 1.23 kg.

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    ...omphaloskepsis often...
  7. Re:Human peer pressure shrinks brain by Hognoxious · · Score: 4, Funny

    They should like *totally* make a movie of that or something.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."
  8. Re:However, by the time you get as social as insec by Anonymous Coward · · Score: 2, Insightful

    But insects aren't really social. They form big colonies, but they predominantly act as a large group of individuals acting for the good of the group. There's no concept of social relationships between individuals in an insect colony.

    Humans don't do the big picture stuff as well, but we can maintain unique relationships with up to about 150 other humans or animals (Dunbar's number). Whales, dolphins, and also elephants and many primate species seem to do the same.

  9. Re:Human peer pressure shrinks brain by Immerman · · Score: 5, Interesting

    Indeed, the problem for us nerds/geeks was not that we were intelligent, it was that we chose to apply that intelligence to "interesting things" rather than social maneuvering. I knew plenty of smart kids who were quite popular, I just found their hobbies utterly uninteresting.

    Fortunately, that problem faded greatly upon entering adulthood - there's obviously still a lot of brainy social misfits, but there's far less social advantage to harassing them, and far more potential mates who have grown past their raging hormones to appreciate them.

    I suspect a great deal of the problem is this recent concept of "teenager" artificially imposing an extended "child" status on individuals who are biologically entering the period where they should be establishing their position within the tribe by making genuine contributions. Instead we keep them locked up in day-care institutions with nothing productive to do all day, so that social maneuvering is basically the *only* skill that contributes to social status. Any time you put humans in that situation it tends to bring out the worst in them - be it prison or upper-middle class housewives lunching and back-biting to pass the time.

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    --- Most topics have many sides worth arguing, allow me to take one opposite you.
  10. Re:However, by the time you get as social as insec by Immerman · · Score: 2

    Not clones, but all siblings with the same mother. And little if any potential to reproduce - their gene-line is preserved only through their mother and the queens and drones she lays.

    Not sure about ants, but I recall that honeybee workers are females capable of reproducing, but due to some rather complex genetics they're actually a lot more closely related to their siblings than their own offspring.

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    --- Most topics have many sides worth arguing, allow me to take one opposite you.
  11. Re:Human peer pressure shrinks brain by Gilgaron · · Score: 2

    Sure, you also hear about competitive magnet schools where kids will try to sabotage each other academically. A bunch of teenagers together are going to get competitive as they are forming their identities and they're going to key in on whatever the local culture is glorifying, whether being valedictorian or quarterback is what makes you popular with the dominant social clade.