Magnus Johansson via Wikimedia Commons // CC BY-SA 2.0
Magnus Johansson via Wikimedia Commons // CC BY-SA 2.0

Scientists Say Apes Can Predict Human Mistakes

Magnus Johansson via Wikimedia Commons // CC BY-SA 2.0
Magnus Johansson via Wikimedia Commons // CC BY-SA 2.0

Everybody’s got that one friend who just keeps making terrible choices. You can see the consequences a mile off; unfortunately, they can’t, and you know it. This concept—that we can anticipate other people’s beliefs or behaviors, even when we know they’re mistaken—seems uniquely human. Now Japanese researchers say apes can do it, too, albeit on a much simpler scale. They published their findings in the journal Science.

Your recognition of your friend’s thoughts, beliefs, and feelings is what’s called the Theory of Mind (ToM). Possessing an awareness of other people’s inner lives is a complex mental task, and for a very long time, scientists believed we were the only ones who could manage it.

But the more we learn about other animals’ brains, the more our certainty in our own supremacy unravels. The last few decades have shown us that other animals are indeed capable of all kinds of sophisticated thinking, from reading MRIs to fashioning tools. The idea that other animals might use ToM began to seem a little less far-fetched. Still, how would you test it?

Testing animal intelligence is tricky for a lot of reasons. First, it’s very hard for humans—even scientists—to set aside their human-centric perspective. This results in experiments that measure how well animals can act like people, which is definitely not the same as measuring their intelligence. Second, well, animals can’t talk, and while we’ve gotten pretty good at interpreting certain behaviors, that doesn’t mean we understand one another.

Fortunately, many of us have pretty good chimp and orangutan substitutes living right in our homes: little kids. Studies have found similar levels of intelligence in small children and non-human apes, which means that experiments that work with babies may translate well for our hairier cousins.

Because babies can’t tell us what they’re thinking, researchers let them show us instead, often using a technique called gaze tracking. Researchers show a baby something, whether that’s a puppet or her mom or a scary mask, then videotape the baby’s response to track where her eyes move. The idea is that the more strongly the baby feels about something, the longer she’ll look at it. Babies have no poker faces.

Animal behavior researchers have adopted gaze tracking for use with their own subjects and have taken it in some pretty interesting directions. Last year, Kyoto University’s Fumihiro Kano created the world’s first horror movies for apes, then watched the apes watching them. After repeated viewings, the apes apparently developed “favorite” moments and would pay even closer attention when they knew those parts were coming up.

For the latest study, Kano teamed up with researchers from the U.S., the UK, and Germany to determine if other primates could use ToM. They produced another series of short films featuring a human and an “ape,” King Kong (KK, actually a person in a gorilla suit), essentially messing with each other’s heads.

In one movie, the “person” hid an object in one place. Then KK came in and moved the object to a new hiding spot. In one version of the film, the person was there and watched KK hiding their stuff; in the other, KK was unobserved. Would apes who watched the second version of the movie expect the person to look for the treasure in their original hiding spot? In other words, could they anticipate that this deceived person would act like someone who’d been deceived?

Yep. This sneaky version of the story was shown to 22 different apes (a mixture of chimpanzees, orangutans, and bonobos). Of those 22, 17 stared at the original hiding spot when the person came onscreen to start searching. They could guess what the poor sucker was about to do.

Frans de Waal is a primatologist and a legend in the field of animal behavior. He was unaffiliated with the study, but praised it in an editorial in the same issue of Science. “This nonverbal paradigm is a genuine breakthrough not only because it avoids an undue reliance on language skills required to understand narrative and questions in theory of mind testing in children,” he wrote, “but also because it highlights the mental continuity between great apes and humans.”

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Squirrels Are Probably More Organized Than You, Study Finds

Despite having a brain that's slightly bigger than the size of a peanut M&M, squirrels have a fascinating, razor-sharp instinct when it comes to survival. They know that acorns that are high in fat and sprout late are perfect for long-term storage, so they salvage them for winter and eat the less nutritionally dense white-oak acorns right away. They also tend to remember where they put their acorn stash rather than relying solely on smell. Like nature's perfect stunt performer, they can even fall out of trees in a way that minimizes physical damage. Now, researchers at the University of California, Berkeley have unveiled a newly discovered part of a squirrel's hoarding strategy, Atlas Obscura reports.

The researchers tracked 45 wild fox squirrels on the UC-Berkeley campus for nearly two years. They made available to the squirrels four different types of nuts—walnuts, pecans, almonds, and hazelnuts. Sometimes the animals were given a single type of nut, and other times the nuts were mixed. Either way, the squirrels promptly sorted and stored their food according to type—walnuts went in one hiding place, almonds in another, and so on.

This type of behavior is known as "chunking" and makes it easier to retrieve data in memory. In doing this, a squirrel won't have to visit several different places looking for pecans: They know just where the main supply is. Squirrels can stockpile up to 10,000 nuts a year, so it's essential for them to know which type of nut is where.

The study, published in Royal Society Open Science, also indicated that squirrels seem to understand nuts have weight, choosing to carry heavier acquisitions to a different location than lighter nuts.

Squirrels being squirrels, they were happy to be gifted an assortment of nuts during the experiment, but there was one wrinkle: Rather than stash them away, sometimes they'd just eat them on the spot.

[h/t Atlas Obscura]

10 Amazing Facts About Our Bond With Dogs

They’ve been our companions for tens of thousands of years. They share our beds, follow us into the bathroom, and star in our holiday cards. The beautiful friendship between Homo sapiens and Canis lupus familiaris has had some surprising effects on both species—read on to learn more about the ways we’ve helped each other along the way.


Living with furry friends, especially dogs, has been shown to decrease babies’ and kids’ risk for asthma, allergies, and other immune conditions. Some studies have found that the benefits can begin as early as the womb. Scientists aren’t completely sure why this happens; it may be that bacteria on the dogs’ bodies can help give our immune systems a boost during a crucial moment in our development.


Keeping your phone loaded with pictures of your pet may pay off in the long run. In one 2012 experiment, people who looked at pictures of puppies scored higher on tasks that required their close attention. Photos of older dogs were less effective; the researchers say it might be that baby animals inspire a specific type of positive emotion and mental activation.


Dogs are social animals; that’s part of the reason we were able to tame them in the first place. And once we take them in, they really start to care what we think. Experiments with dogs and their owners have shown that when given the choice between snacks and praise, most prefer being told what good dogs they are.


Sharing your life with a drooling, adoring furry friend is good for your attitude and your stress levels. Spending time with dogs can ease tension and stress. Studies have found that this is especially true in high-stress situations like crises, natural disasters, and the office.


Reduced stress is its own reward, but it can also have long-term health benefits, including lower blood pressure, lowered heart rate, and a decreased risk of heart disease. This works even in little doses: just petting a dog for a few minutes sends feel-good chemicals to the brain and can soothe a frazzled nervous system.


All those millennia together have made a real impression on dogs’ brains. One 2016 study found that dogs could read and respond to the emotions on human faces, even in photographs. This is especially cool when you consider the major differences in body language between our two species. Dogs don’t smile, but they still know what our grin means when they see it.


There’s nothing like an “I’ve-got-to-pee-RIGHT-NOW” bark to get you up and out the door. For obvious reasons, dog owners get more casual exercise than other people. This, in turn, can also lower stress levels and improve heart health.


Spoken language, like body language, differs drastically between our two species, but that hasn’t stopped dogs from trying to figure ours out. A series of Hungarian experiments using MRI scanners found that dogs’ brains responded to human voices speaking both positive words and with positive tone. This was true even when the positive words were spoken in a neutral tone (“good boy”) and the positive tone was applied to a neutral phrase (“however!!!”). They get us.


The good news for dogs is that domestication has given them a steady source of food, shelter, and companionship. The bad news is that all this cushy living has dulled their edges somewhat. Compared to the wolves from which they descended, pet dogs have weaker senses of hearing and smell, and they’re worse at problem-solving tasks. But this isn’t a problem, per se; they’ve simply evolved and been bred to prioritize one set of survival skills (coexisting with people) over another (sharp senses and keen minds).


The bond between us and our dogs is real, and may trace all the way down into dogs’ DNA. Experiments have found that the most sociable pet dogs have genetic mutations that appear to make them more interested in people. Without these abnormalities, experts say, we might never have been able to domesticate dogs in the first place.

Dogs make our lives a whole lot happier and healthier. (You can’t argue with science!) Looking to return the favor? Consider a monthly subscription to BarkBox. Your favorite pup will get a package filled with treats, toys, and other goodies. Visit BarkBox to learn more.