Monkeys Learn to Recognize Themselves in a Mirror – And Promptly Check Out Their Butts

By Carl Engelking | January 8, 2015 2:30 pm
This is a scene from experiments showing that rhesus monkeys can learn to recognize themselves in the mirror. (Neng Gong and colleagues/Current Biology 2015)

This is a scene from experiments showing that rhesus monkeys can learn to recognize themselves in the mirror. (Neng Gong and colleagues/Current Biology 2015)

What would you do if you saw yourself in a mirror for the first time?

When, after weeks of training, rhesus monkeys learned the true identity of their reflections, one of the first things they did was check out all the locales on their bodies they’d never before seen — and we mean every intimate nook and cranny.

The fact that these monkeys could look in a mirror and recognize those nether regions was stunning. That’s because rhesus monkeys have never proven that they can recognize themselves in a mirror. However, researchers proved that, through a little training, they could foster a certain sense of self-awareness in these primates. And that could teach us more about how the brains of humans and other primates allow them to self-recognize in a mirror.

Monkey See, Monkey…Hey, That’s Me!

Many creatures in the animal kingdom know it’s them in their reflections. Humans do (beginning as young as 2), as do dolphins, great apes and elephants, to name a few. We know rhesus monkeys struggle at this because they routinely fail a common test for self-recognition called the standard mark test. Basically, researchers put a colored, odorless marking on the face of an animal or shine a laser pointer at a particular place on their body. If, while looking in the mirror, the animal touches its own face or rubs at the mark, they pass the test.

Some animals, like pigeons, fail this test initially, but they can learn to recognize their reflection with extensive conditioning. Knowing this, researchers wondered if rhesus monkeys were the same.

So, they gathered seven monkeys and started a simple training regimen. They sat each monkey in a secure chair facing a mirror. Then they shined a red laser dot that caused mild skin irritation somewhere on each monkey’s face. Every time monkeys pawed at the dot they received a treat. As their training progressed, monkeys pawed at a non-irritating laser dot, and eventually touched an odorless red dye mark on their faces when looking in the mirror.

A New Skill

After receiving their training, the monkeys were ready for their final test: the standard mark test. Researchers shined a laser pointer at different parts of the monkeys’ bodies while they were in their home cages, which were decked out with floor-to-ceiling mirrors. When the trained monkeys looked in the mirror, they rubbed and picked at the marking — passing the test for the first time. Untrained monkeys, on the other hand, didn’t acknowledge the laser dot when they looked in the mirror.

To prove the monkeys’ newfound knowledge wasn’t just a conditioned response (i.e. pawing their own faces whenever they saw a monkey face with a dot), researchers put them in a cage with a marked, untrained monkey. Rather than pawing their own faces, the trained monkeys rubbed and licked at their untrained counterparts’ mark. Thus, trained monkeys weren’t rubbing their faces simply at the site of a red mark. Researchers published their findings Thursday in the journal Current Biology.

Monkey Vain

And what did these monkeys do with their new sense of self? They looked at their genitals, of course. Without any prompting, researchers caught the little narcissists contorting and spreading their legs in front of the mirror to get a better look at previously unseen corners of their bodies. But who are we to judge?

Researchers say their study is far from simply monkey business, however. Studying the way monkeys’ brains change during their mirror training could guide researchers toward the neural origins of self-recognition. Although humans can do this automatically, this skill is impaired in people with mental disabilities, autism or Alzheimer’s. Knowing how monkeys acquire this skill could, perhaps, help people with these conditions learn it as well.

In the meantime, we have a tip for those exhibitionist monkeys: Save yourself the contortions and just invest in a Belfie like the rest of us.

CATEGORIZED UNDER: Living World, top posts
  • cactusneedle

    Tells me that humans are more like monkeys than we thought.

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  • wildemar

    > rubbing their faces simply at the *site* of a red mark

    Shouldn’t that be ‘sight’?

    • Michael A Mitchell

      No, as they were rubbing themselves at the location where the red mark appeared in the reflected image.

      • Larry Etkin

        Actually, a most proper description might actually use both homonyms: at its “sight” of the “site” of the red mark.

  • Hana Sheala

    Ugh I can see more autiístic people will get their boundaries pushed in compliance training to look indistinguisable from their peers. :(

  • Dirty Harry

    Actually some of them thought they had seen Moochelle.

    • Terry Simpson

      Shame on you.

    • Don’t Even Try It!

      HAHAHA! Good one!

    • Boosh Woggle

      *gasp* a conservative with the sense of humor of a 12 year old!? SHOCKED, I tell ya.

  • Idaws Kidaws

    Has it been tested whether they will react in the same way if a red dot appears on a fellow monkey instead of their reflections???

    • Larry Etkin

      Yes. The article specifically noted, “the trained monkeys rubbed and licked at their untrained counterparts’ mark,” in the last paragraph of the next to last section.

  • sonamdawa

    Although it is a test but some of picture really make some of us uneasy. I mean how animal were treated badly under the name of scientific research and test !!!!!!!!!!!!!!!

    • Don’t Even Try It!

      Get a life.

    • Boothj1985

      I agree, they’re forced into these experiments with no say over it what so ever.

  • Eric Lipps

    What’s interesting is that the monkeys quickly got the idea not merely that they could look at themselves but that the monkeys they saw in the mirror were themselves. Most other animals can’t do it, partly because they lack the cognitive skills and partly because they depend as much on smell as on sight for recognition and a reflection, of course, has no smell.

  • gendotte

    Didn’t know that monkeys could be Republicans.

    • BackwardsBoy

      The monkeys are far more self aware than Progressives. But both display the same behavior through their fascination with genitals.

      • Boosh Woggle

        fun fact: the most porn viewed per capita in the USA is in the conservative state of Utah.

    • Rigel54

      Republicans aren’t so much self-aware as self absorbed.

      • gendotte

        I bet the monkeys have a wide stance too. Oh, and BackwardsBoy (good name), Can you name one thing in the past century, that demonstrably helped the middle class, that the Republican Party did not oppose? Can you name one thing in the past century, that demonstrably helped the middle class, that the Republican Party accomplished?

    • Boosh Woggle

      What do sweet innocent monkeys have to do with the stupid political parties of humans? (Democrat or Republican). Why being politics into this?

  • Elwoodathome

    Not surprised at the Genital behavior at all. Several years ago I was at a small zoo outside of London, Ontario. We had our 4 year old blonde haired granddaughter with us and a small Rhesus Monkey got very sexually excited at the sight of her and proceeded to show us his rather long, skinny equipment. He was so proud of it we had to quickly remove our Granddaughter from the area, such was his excitement. His screeching and growling was almost scary. I am guessing he thought she was a female of his species given his display of affection! Sounds funny but he was one confused primate!

  • stinkbug

    Studies have yet to prove whether they can discern it from their elbow.

  • Lewis Cowles

    And what did these monkeys do with their new sense of self? They looked at their genitals, of course.

    Nice, thanks for over-sharing science…


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