Monkeys are intelligent animals known for their curiosity and ability to problem-solve. They are also highly observant and are capable of recognizing patterns and changes in their environment. This intelligence and awareness make them prime candidates for reacting to magic tricks and illusions. When a monkey is presented with a magic trick, it is not uncommon for them to become fascinated and intrigued by the unexpected. They may display a range of reactions, which can be similar to those of humans. Some monkeys may tilt their heads to the side, as if trying to understand the trick, while others may become startled or even frightened by the sudden change in their perceived reality.

Sleight-of-hand magic trick only fools monkeys with opposable thumbs

Illusion involving a hidden thumb confounds capuchin and squirrel monkeys for the same reason as humans – it misdirects the expected outcomes of actions they can carry out.

This mirroring in our neural motor system might explain why the French drop worked for the capuchins and squirrel monkeys but not for marmosets

Nicola Clayton

By performing a famous magic trick for three species of monkey with differing hand structures, scientists have discovered that – in order to deceive – a conjuror needs the same anatomy as their audience.

Psychologists used a sleight-of-hand trick called the French drop, in which an object appears to vanish when a spectator assumes it is taken from one hand by the hidden thumb of the other hand.

The study, carried out by the University of Cambridge’s Comparative Cognition Lab, found that monkeys lacking opposable thumbs did not fall for the assumption – staying wise to the whereabouts of tasty treats a magician tried to make disappear.

The research suggest that sharing a biomechanical ability may be necessary for accurately anticipating the movements of those same limbs in other individuals.

This is true even when those apparently accurate predictions end in befuddlement at the hands of an illusionist. The study is published today in the journal Current Biology.

“Magicians use intricate techniques to mislead the observer into experiencing the impossible. It is a great way to study blind spots in attention and perception,” said Dr Elias Garcia-Pelegrin, who has practiced magic for a decade, and conducted the experimental work during his PhD at Cambridge.

“By investigating how species of primates experience magic, we can understand more about the evolutionary roots of cognitive shortcomings that leave us exposed to the cunning of magicians.”

“In this case, whether having the manual capability to produce an action, such as holding an item between finger and thumb, is necessary for predicting the effects of that action in others,” said Garcia-Pelegrin, recently appointed an assistant professor at the National University of Singapore.

The French drop is often the first trick any budding magician sets out to master.

A coin is displayed in one hand. The other hand reaches over and grabs it. The palm of the second hand faces inwards, with the magician’s thumb concealed behind fingers.

The audience knows the thumb is lurking – ready to grip – so assumes the coin has been taken when it is no longer visible. Their attention follows the second hand, only to find it empty at 'the reveal'. The magician had secretly dropped the coin into the palm of the original hand.

Food morsels replaced coins for the monkeys, and were given as rewards – but only if the animals guessed the correct hand. Scientists predicted that monkeys with opposable thumbs would act like human audiences: assume the hidden thumb had grabbed the item, and choose the wrong hand.

They repeatedly performed the French drop on 24 monkeys. Eight capuchins were dazzled with peanuts, eight squirrel monkeys with dried mealworms, and eight marmosets with marshmallows.

Capuchins are famed for dexterity, and use stone tools to crack nuts in the wild. They can waggle each finger, and have opposable thumbs allowing 'precision grip' between thumb and forefingers.

The capuchins were regularly fooled by the French drop (81% of the time). They mostly chose the empty second hand, and experienced a paucity of peanuts as a result.

Squirrel monkeys are much less dextrous than capuchins, with limited thumb rotation, but can oppose their thumbs. As such, they are still familiar with a hidden thumb interacting with fingers. However, they cannot perform a ‘precision grip’ in the same way as capuchins and humans.

Yet squirrel monkeys were routinely misled by vanishing mealworms (93% of the time). “Squirrel monkeys cannot do full precision grips, but they were still fooled. This suggests that a monkey doesn’t have to be expert in a movement in order to predict it, just roughly able to do it,” said Garcia-Pelegrin.

Marmosets do not have opposable thumbs. Their thumbs align with their fingers to make five equidistant digits, ideal for climbing thick tree trunks. Marmosets were rarely taken in by magic (just 6% of the time). They simply chose the hand in which the marshmallow was initially placed, and stuck with it.

Previous work from the Cambridge team shows that species without hands at all, in this case birds from the corvid family, namely Eurasian jays, make similar choices as marmosets when confronted with the French drop.

The team also tried nullifying the tricks by actually completing the hand-to-hand transfers, instead of misdirecting with a French drop. This time, the capuchins and squirrel monkeys anticipated correctly and dined out, and the marmosets missed out.

Finally, the scientists devised their own version of the French drop, which they call the “Power drop”. It utilises a hand action that all the monkey species can perform – essentially a full fist grab. The power drop fooled all of the monkey species the vast majority of the time.

“There is increasing evidence that the same parts of the nervous system used when we perform an action are also activated when we watch that action performed by others,” said Prof Nicola Clayton FRS, senior author of the study from Cambridge’s Department of Psychology.

“This mirroring in our neural motor system might explain why the French drop worked for the capuchins and squirrel monkeys but not for marmosets.”

“It’s about the embodiment of knowledge,” added Clayton. “How one’s fingers and thumbs move helps to shape the way we think, and the assumptions we make about the world – as well as what others might see, remember and anticipate, based on their expectations.”

“Our work raises the intriguing possibility that an individual’s inherent physical capability heavily influences their perception, their memory of what they think they saw, and their ability to predict manual movements of those around them.”

Another co-author of the study, Clive Wilkins, Artist in Residence at Cambridge’s Department of Psychology, is a professional magician and Member of the Magic Circle.

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Orangutans at Miami Zoo Use iPads to Communicate

At the Miami Zoo's Jungle Island, handlers are interacting with orangutans using the iPad. The apes use the tablet to identify items they're familiar with and express their wants and needs.

In this Feb. 21, 2012 photo, an orangutan works with an iPad at Jungle Island in Miami. (AP Photo/J Pat Carter) J Pat Carter

The iPad is by far the most adored tablet in the human world. The numbers speak for themselves. But what you may not know is that members of the animal kingdom dig the 9.7-inch tablet too -- particularly a clan of six orangutans at the Miami Zoo.

At the Miami Zoo's Jungle Island, handlers are interacting with orangutans using the iPad. The apes use the tablet to identify items they're familiar with, and express their wants and needs. This is done primarily through an app designed for autistic children that displays an array of object images onscreen.

"We’ll ask them to identify 'Where’s the coconut?', and they’ll point it out," Linda Jacobs, who oversees the Jungle Island program, told Wired. "We want to build from that and give them a choice in what they have for dinner -- show them pictures of every vegetable we have available that day, and let them pick, giving them the opportunity to have choices."

Orangutans are very intelligent, but lack voice boxes and vocal cords, which can make communication difficult. Up until now, zoo keepers have been using sign language to communicate with them. Using the iPad gives the orangutans another form of communication with humans, provides them with mental stimulation, and also gives those who don't know sign language a chance to interact with humans.

The six orangutans at the Miami Zoo -- 35-year-old Connie, 33-year-old Sinbad, 14-year-old Hannah, 12-year-old Jake, and 8-year-old twin girls Peanut and Pumpkin -- were first introduced to the iPad last summer. Initially, the orangutans were just shown the iPad to desensitize them. Next the trainers asked them to touch the iPad without pulling it into the cage. "They catch on so quickly, it wasn't long before we started showing them pictures and identifying different objects with them," Jacobs said.

Sinbad and Connie aren't so keen on the tablet. "I like to compare the two older ones to my parents -- I keep trying to get them to use an iPad and they’re just not interested," Jacobs said. The other orangutans, though, are very excited by the tablet. They take turns getting to use it, and all run to be the first one to handle it, Jacobs said.

"They really are so intelligent that I think there’s no limit to what they can learn," Jacobs said. "It's just about developing the technology to make it possible."

Due to their curious nature and tough nails, the orangutans don't actually get to hold the iPad (which is housed in an Otter Box case) in the cage themselves. Instead, a trainer holds it outside the cage. If left to their own devices, the primates would take it apart to see how it works, Jacobs said, so it wouldn't last that long.

In the future, Jacobs hopes to set up a form of video conferencing so the apes can meet and interact with their counterparts at other zoos across the world (an organization called Orangutan Outreach is currently working on this with donated iPads at other U.S. zoos). She also hopes that this endeavor will bring more awareness to orangutans, which are greatly endangered in the wild because of deforestation.

Did the Baboon Feel the Magic?

Not yet as popular as cats and dogs in superhero outfits, there is a growing category of YouTube video featuring magicians performing for various animal species. The latest one making the rounds on Facebook is a short clip of a baboon in a zoo enclosure watching a sleight-of hand card vanish through a glass barrier.

The video, only about 10 seconds long, shows a sleepy baboon sitting against the glass divider, clearly bored with the constant stream of visitors. But not for long. From the other side of the glass, a middle-aged man extends his hand. He’s holding a small white piece of paper or plastic, the size of a playing card. The man’s white baseball cap and red polo shirt don’t signal “magician” at first. But this guy is clearly adept at legerdemain. He shows the card to the primate, as if saying “This is a regular card from a regular deck.” At first, no reaction. The baboon’s half-closed eyes stay that way. It really couldn’t care less. After millions of juveniles sticking their tongues out at it, knocking on the glass day in and day out, who cares about yet another tourist, never mind the card brandishing?

Then, a flick of the wrist and POOF! The card is gone. The man shows his empty palm to the monkey. Now’s he got the animal’s attention! The baboon raises his eyebrows in apparent amazement, and a fraction of a second later, lunges at the man, jaws open wide. It is only thanks to the glass barrier that the man gets to keep all his fingers. The monkey looks in the man’s eyes menacingly. “You better produce that card now, or there’ll be hell to pay,” it seems to imply. The magician makes the card re-appear with another wrist snap. The baboon now looks much happier and reaches lightning-like for the card with his hand—but of course, there’s the glass barrier in between. Then the video ends.

There has been extensive online commentary concerning the meaning of the primate’s ostensibly all-too-human reaction. The general consensus appears to be that the baboon felt the magic in much the same way as a human spectator would. There have been some notable exceptions, however: in an interview for Caitlin Roper from WIRED, primatologist Frans de Waals noted that the baboon’s reaction might have been due less to the magic trick and more to unwelcome eye-contact from the human (many primates perceive direct eye-contact as aggression). One problem with that possibility is that the eye contact seems to happen only after the trick and the animal’s pounce (although it’s hard to know for sure when the initial eye-contact occurs, because we never see the man’s face).

Caitlin Roper also contacted me for my impressions on the baboon’s reaction. By the time we got hold of each other, her article had been already published… so you won’t find my opinion there. But this is my hypothesis: the monkey’s reaction was in response to the magic trick, but it was not the same reaction as a human would have had: at least a human over the age of 5.

I have put forward previously that animals’ perception of the conjuring arts –perhaps with the exception of great apes—is different from that from human adults. Sure, animals can be surprised by vanishing objects, just as humans can. But shock is not the only element of magic, albeit it is certainly an important one. There is also awe and enjoyment. Perhaps even happiness: a common reaction to a magic trick is joyful laughter. It’s not that the magic is funny, but that it is delightful.

But why should magic delight us? One possibility is that, just like a benign joke, a magic trick is a type of harmless transgression. You laugh in a magic show because, even though you’ve witnessed the breakage of physical reality, you know you’re safe. If you thought the magic was for real, you might be terrified. Or at least really annoyed.

That baboon did not have a joyous reaction to the magic.

Which brings me back to the issue of magic for adults versus children. A common misconception is that magic is intended for children, when in fact the best magic spectators are adult ones. Children under the age of 5, in particular, do not enjoy magic very much. I have heard magicians express this sentiment many times. The explanations vary: perhaps children’s developing attentional systems are less susceptible to misdirection than adult ones, or maybe young children have not yet developed strong theories about the laws of nature, so everything is equally magical (or non-magical) to them. Whatever the reason, I have had the opportunity to witness this phenomenon first hand. Six or seven years ago, Stephen Macknik and I visited theatrical pickpocket Apollo Robbins in Las Vegas, to plan a research study in which we were collaborating. We brought along our oldest child, then a toddler, for the trip. Apollo was kind enough to demonstrate extraordinary sleight-of-hand magic for our family: he gave our child coins, and then stole them without him (or us) noticing, only to make them re-appear in a different part of the boy’s body. Over and over and over. Steve and I were laughing helplessly, completely enchanted, thoroughly enjoying ourselves.

Our kid? Not so much.

He. Was. Mad. The bad man had given him some coins, and then taken them away for no good reason. What if the man had amazing prestidigitation skills? He had no right to steal those coins! The injustice! Our son started crying in anger. And yes, you guessed it: he kind of looked like a baby baboon.

The views expressed are those of the author(s) and are not necessarily those of Scientific American.

Some monkeys may tilt their heads to the side, as if trying to understand the trick, while others may become startled or even frightened by the sudden change in their perceived reality. In some cases, monkeys may try to interact with the magic trick or illusion, as they attempt to figure out the mechanics behind it. They may touch or inspect the objects involved, showing their innate curiosity and problem-solving skills.

Monkeys have been observed attempting to replicate the magic trick themselves or trying to understand how the illusion is created. It is worth noting that not all monkeys will necessarily react to magic tricks in the same way. Just like humans, monkeys have unique personalities and temperaments, which can influence their response to magic. Some monkeys may be more cautious and skeptical, whereas others may be more adventurous and playful, allowing them to embrace the magic trick with enthusiasm. Overall, monkeys reacting to magic can be a fascinating and entertaining sight. Their intelligence and ability to adapt to new situations make them ideal candidates for experiencing and reacting to the surprises and illusions presented by magic tricks. By observing their reactions, researchers can gain insights into their cognitive abilities and how they perceive the world around them..

Reviews for "Fascinating Monkey Reactions to Mind-Bending Magic"

1. John - 2/5 stars - I was really disappointed with "Monkey reacts to magic". I had high hopes for an entertaining video, but it fell flat for me. The monkey's reactions seemed forced and scripted, and it took away from the genuine surprise and amazement I was expecting. The tricks themselves were also quite lackluster and didn't add any wow-factor. Overall, I found it to be quite underwhelming.

2. Sarah - 1/5 stars - "Monkey reacts to magic" was a complete waste of time. The monkey's reactions were so obviously staged and it felt like I was watching a poorly acted performance. The tricks themselves were nothing special and lacked any real creativity. I couldn't believe I wasted my time watching this.

3. Mark - 2.5/5 stars - I had mixed feelings about "Monkey reacts to magic". On one hand, the monkey was adorable and brought some entertainment value. However, the tricks were repetitive and there wasn't enough variety to keep me engaged. The reactions often seemed exaggerated and it felt like the video was more about the monkey's performance than the actual magic tricks. It didn't meet my expectations and left me wanting more.

4. Emily - 1/5 stars - I found "Monkey reacts to magic" to be completely uninteresting and unoriginal. The tricks were predictable and didn't offer anything new or exciting. The monkey's reactions were over-the-top and felt forced, making it difficult to connect with the content. I would not recommend wasting your time on this video.

Witness the Mesmerizing Monkey Reactions to Magic Tricks