Great Apes Understand When Humans Are Wrong

Buttelmann et al (2017)
Buttelmann et al (2017)

Humans aren’t the only ones who can spot when their friends are about to make a mistake. A new study of chimpanzees, bonobos, and orangutans has found that our great ape cousins can recognize and attempt to correct false beliefs in others—an ability once thought to belong to humans alone. The findings were published in the journal PLOS One.

It’s called Theory of Mind (ToM): the idea that an individual is aware that others have thoughts and feelings different from their own. Because it requires such complex cognitive processing, scientists have long presumed that we’re the only animals that can do it. However, a series of recent studies has called that presumption into question. In 2015, Japanese primatologists created custom horror movies for apes, then observed the apes watching them to see if they could follow the plot. Then in 2016, they made new movies, specially designed to test the apes’ response to watching other apes (actually people in ape costumes) make mistakes.

The movies showed the fake apes being tricked, then having to make a decision based on faulty information. And sure enough, the audience apes’ eyes lingered on the wrong option onscreen, even though they knew where the right option was. They could predict that the actors were about to get it wrong.

The latest experiment takes these discoveries one step farther, by giving apes a chance to help the hapless actor make the right decision. Researchers taught 34 apes to make a simple, rational decision by placing a noisemaker inside one of two locked boxes while the apes were watching. The ape participants were then asked to select the box with the object inside. Next, they set up a little drama. One experimenter would place the object in the box and lock it, then briefly leave the room. While they were gone, another person would come in, remove the object from the first box, place it inside the second box, then exit before the first person returned.

At this point, the ape knew something the experimenter theoretically did not: where the noisemaker was really hidden. When the experimenter came back, they began pretending to try to open the wrong box. More than 75 percent of the time, the apes would reach for, and help them unlock, the right box instead.

In other versions of the drama, where the experimenter watched the sneak switch the object’s location, the apes didn’t seem to care which box the experimenter eventually opened. They knew the experimenter had this handled. The authors say the findings are another strike against the idea that ToM is a human-only phenomenon.

Developmental psychologist Uta Frith was unaffiliated with the research, but told The Guardian that she found it encouraging. “That is very nice because in evolution there is nothing that comes out of the blue from nowhere.”

10 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

Amazon

Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

Buy it: Amazon

2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

Amazon

Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

Buy them: Amazon, Amazon

3. Yeti Rambler 18-Ounce Bottle; $48

Amazon

Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

Buy it: Amazon

4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

Amazon

The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

Buy it: Amazon

5. National Geographic Adventure Edition Road Atlas; $19

Amazon

Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

Buy it: Amazon

6. Adventure Medical Kits Hiker First-Aid Kit; $25

Amazon

This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

Buy it: Amazon

7. Hiker Hunger Ultralight Trekking Poles; $70

Amazon

Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

Buy it: Amazon

8. Leatherman Signal Camping Multitool; $120

Amazon

What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

Buy it: Amazon

9. RAVPower Power Bank; $24

Amazon

Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

Buy it: Amazon

10. Pack of Four Indestructible Field Books; $14

Amazon

Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

Buy it: Amazon

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10 Curious Facts About the Platypus

"Who are you calling a hoax?!"
"Who are you calling a hoax?!"
iStock/JohnCarnemolla

The platypus is arguably one of the most distinct animals on the planet. Here are a few things you might not have known about this quirky creature.

1. Platypuses don’t have stomachs.

Platypuses (platypodes and platypi are technically also correct, but much rarer in use) aren't the only animals to forgo an acid-producing part of the gut; spiny echidnas, and nearly a quarter of living fishes all have a gullet that connects directly to their intestines.

2. Platypus bills give them a “sixth sense.”

A platypus’s bill has thousands of cells that give it a sort of sixth sense, allowing them to detect the electric fields generated by all living things. It’s so sensitive that the platypus can hunt with its eyes, ears, and nose all closed, relying entirely on the bill’s electrolocation.

3. Platypuses used to be giant.

The ancient versions of a lot of modern animals, including penguins, were oversized monsters compared to the animals we know today—and platypuses are no different. In 2013, the discovery of a single tooth helped researchers identify a prehistoric platypus that was more than three feet long—double the size of the modern animal.

4. The platypus is a monotreme—which means “single hole” in Greek.

Platypuses are one of only five species of extant monotremes—just them and four species of echidna—which split from the rest of the mammals 166 million years ago. These egg-laying mammals get their name from the hole that serves as both an anus and a urino-genital opening. In 2008, scientists deciphered the entire DNA of the duck-billed platypus and determined that, in accordance with the animal’s somewhat bizarre appearance, the platypus shared genes with reptiles, birds, and mammals.

5. Platypuses nurse without nipples.

iStock

Although platypuses are born out of leathery eggs, the babies nurse from their mother. Female platypuses, however, don’t have nipples. Instead, their milk is released out of mammary gland ducts on their abdomen. The babies drink it up by sucking it out the folds of their mother's skin, or her fur.

6. Male platypuses have venomous spurs.

Platypuses are one of just a few venomous mammals, which is one of their more reptilian characteristics. But unlike snakes, a platypus’s venom isn’t in his teeth. Instead, males have a hollow spur on each hind leg from which venom is dispensed—but only sometimes. Although the spur itself is always there, the venom gland to which it is connected is seasonally-activated and only produces venom during mating season, indicating that its use is for fending off competing males.

7. Platypuses have retractable webbing.

Although they can only stay submerged in water for a few minutes—they are mammals, after all—platypuses are much better suited to scooting around in water than they are on land. Much like an otter, they prune their thick coat to add air bubbles that act as insulation in the cool rivers where they hunt. Out on land, the platypus's short limbs mean it has to exert 30 percent more energy than a similarly sized land-based mammal just to move around. All that said, they do have one particular adaptation to ease their terrestrial travel: The webbing between their front claws—a boon when paddling through streams—retracts when the platypus ambles up the riverbank to expose sharp claws.

8. Scientists thought the first known platypus was a hoax.

iStock

When the first platypus specimen was sent back to England from Australia in the late 18th century, the scientists who examined it thought that someone was playing a trick on them. "It naturally excites the idea of some deceptive preparation by artificial means," zoologist George Shaw wrote in the first scientific description of the platypus, published in 1799. One of the most remarkable and weird aspects of the platypus—its ability to lay eggs—wasn’t discovered for another 100 years.

9. Platypuses use gravel as makeshift teeth.

Platypuses don’t have teeth inside their bill, which makes it difficult to chew some of their favorite foods—but they have worked out a pretty ingenious solution. Along with worms, insects, shellfish, and whatever else these bottom-feeders scoop up to make a meal out of, the platypus also picks up gravel from the riverbed. The platypus packs it all into pouches in his cheek to carry it up to the surface where it munches away, using the bits of gravel as makeshift teeth to break up tougher food.

10. Platypuses use their tails for all sorts of things.

Unlike beavers, which have very visually similar tails, platypuses don't use their tails to slap the water in warning, or even to move them through the water. Most of the time, the primary function of the platypus's tail is just to store up to nearly half of the animal's body fat in case of a food shortage. A female platypus also uses her tail to hold incubating eggs against her warm body.