TIME animals

Here Is the Biggest Reason You Love Your Dog

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Never mind the petting or playing; it's all about the eyes

Humans are irrational in a whole lot of ways, but nothing quite compares to our love for our dogs. They provide us neither food nor conversation nor, in most cases, protection. What’s more, they cost us a fortune—a big share of the $60 billion Americans spend on all pets per year goes to the 70 million dogs living in 43 million U.S. households.

But never mind. Dogs and humans have created an improbable bond that is nearly as close as the one we share with our own kind. Now, a study in Science reveals one of the reasons the two species love each other so: the secret, it turns out, is in the eyes.

The average dog spends a lot of its time gazing at it owner adoringly, and owners—whether they know it or not—spend a lot of time gazing back. That’s very different from the way things work with other species—particularly the dog’s close cousin, the wolf—which typically use eye contact as a threat display or a means of domination.

To test the effect of the human-dog gaze, a team of researchers headed by Miho Nagasawa of Japan’s Azabu University conducted a pair of experiments, both of which involved the hormone oxytocin, nicknamed the cuddle chemical because it facilitates bonding in humans and many other species. Oxytocin levels skyrocket in people who are in love and in new parents, and breastfeeding blows the doors off the concentrations of the stuff in the mother’s blood and milk, which means it goes straight to the babies, making them feel the love too.

In the first part of Nagasawa’s study, urine samples were collected from 21 pairs of dogs and owners, both before and after experimental sessions in which the owners petted the dogs, talked to the dogs, and often simply gazed at the dogs. As a control group, 11 pairs of owners and hand-raised wolves also provided samples and also performed the interactions.

Consistently, the oxytocin levels of both the dogs and the humans were higher at the end of the sessions—and usually by about the same percentage for each owner-dog pair. But it was among the pairs in which there was a lot more gazing and a lot less touching and talking that the levels were highest—high enough to cross the threshold of statistical significance. None of this was true in the wolf-human pairs.

“The duration of the dog-to-owner gaze…significantly explained the oxytocin-change ratio,” the investigators wrote.

In the second experiment, the investigators similarly collected before-and-after urine samples from dog-human pairs. But this time, either oxytocin or an inert solution was administered to the dogs nasally before the interactions began. Each dog was then released into a room with its owner and two strangers, and though the dogs typically approached their owners and nuzzled them, the humans were instructed neither to talk to the dogs nor touch them back, but simply to meet their gaze.

Of all the dogs, the females that had received the oxytocin gazed at their owners most—and it was those females’ owners whose oxytocin levels were the highest afterwards. Female dogs, the researchers believe, are simply more susceptible to the effects of oxytocin than males—no surprise since they’re the ones who bear and nurse puppies. To the extent that the males were affected by the intranasal dosing at all, the impact might have been blunted by the mere fact that there were strangers in the room.

“The results of experiment 2 may indicate that male dogs were attending to both their owners and to unfamiliar people as a form of vigilance,” the researchers wrote.

Whatever the explanation for the dogs’ behavior, it’s clear that it works. It’s been many thousands of years since dogs climbed aboard the human caravan—guarding our campfires and protecting our livestock in exchange for food and a warm place to sleep. But as with all good friends, the relationship deepened, and as with all good friends too, the right chemistry—literally—is one of the reasons.

TIME animal behavior

What Are Animals Thinking? (Hint: More Than You Suspect)

The mind of an animal is a far richer, more complex thing than most people know — as a new TIME book reveals

Let’s be honest, you’d probably rather die than wake up tomorrow morning and find out you’d turned into an animal. Dying, after all, is inevitable, and there’s even a certain dignity to it: Shakespeare did it, Einstein did it, Galileo and Washington and Twain all did it. And you, someone who was born a human and will live your life as a human, will end your life that way too.

But living that life as an animal — an insensate brute, incapable of reason, abstraction, perhaps even feeling? Unthinkable. Yes, yes, the animals don’t recognize the difference, and neither would you. If you’re a goat, you possess the knowledge of a goat, and that can’t be much. But there’s more to it than that.

Human beings have always had something of a bipolar relationship with the millions of other species with which we share the planet. We are fascinated by them, often dazzled by them. They can be magnificently beautiful, for one thing: the explosive color and frippery of a bird of paradise, the hallucinatory variety of the fish in a coral reef, the otherworldly markings and architecture of a giraffe. Even the plain or ugly animals — consider the naked, leathery grayness of the rhino or elephant — have a certain solidity and equipoise to them. And to see an animal at what appears to be play — the breaching dolphin, the swooping raptor — is to think that it might be fun to have a taste, a tiny taste, of their lives.

But it’s a taste we’d surely spit right out, because as much as we may admire animals, we pity them too: their ignorance, their inconsequence, and their brief, savage lives. It’s in our interest to see them that way — not so much because we need to press our already considerable advantage over them; we don’t. But because we have certain uses in mind for them. We need the animals to work for us — to pull carts, drag plows, lift logs and carry loads, and stand still for a whipping if they don’t. We need them to entertain us, in our circuses and zoos and stage shows. And most of all, we need them to feed us, with their eggs and milk and their very flesh. A few favored beasts do get a pass — dogs, cats, some horses — but the rest are little more than tools for our use.

But that view is becoming impossible to sustain — as a new TIME book reveals. The more deeply scientists look into the animal mind, the more they’re discovering it to be a place of richness, joy, thought and even nuance. There are the parrots that don’t just mimic words but appear to understand them, for example, assembling them into what can only be described as sentences. There are the gorillas and bonobos that can do the same with sign language or pictograms. Those abilities are hard to dismiss, but they also miss the point; they are, in many way, limited gifts — animals doing things humans do, but much less well.

A better measure is the suite of behaviors the animals exhibit on their own: crows that can fashion tools, lions that collaborate on elaborate hunts, dolphins and elephants with signature calls that serve as names, and cultural norms like grieving for their dead and caring for grandchildren. There are the complex, even political societies that hyenas create and the factory-like worlds of bees and ants. There are the abiding friendships among animals, too — not just the pairs of dolphins or horses or dogs that seem inseparable but the cross-species loyalties: the monkey and the dog, the sheep and the elephant, the cat and the crow, members of ordinarily incompatible species that appear never to have thought to fight with or eat one another because, well, no one told them they had to.

Animals, the research is proving, are creatures capable of reflection, bliss, worry and more. Not all of them in the same ways or to the same degrees, surely, but all of them in far deeper measures than we’ve ever believed. The animal mind is nothing like the wasteland it’s been made out to be. And if it’s not the mind you’d want to have as your own, it’s one that is still worth getting to know much better.

(The Animal Mind is now available on newsstands.)

TIME animal behavior

Hey, Did I See You Petting Another Dog?

Who were you seeing last night? And do NOT lie to me.
Stefanie Timmermann—Vetta/Getty Images Who were you seeing last night? And do NOT lie to me.

Man's best friend takes that BFF thing seriously. Pay too much attention to a dog other than your own and you'd better be prepared to explain yourself when you get home.

If the science of animal behavior had an official curse word, it would be “anthropomorphism.” That’s just a fancy term for the sin of assigning human qualities to animals. Your dog might look happy and your cat might seem disdainful, but since you most likely think of your pet as a little person already, your judgements are automatically suspect. You see what you want to see, and that is the opposite of scientific.

But that doesn’t necessarily mean you’re always wrong. It turns out that one rigorous scientific experiment after another has shown that some animals do have mental states that are surprisingly similar to ours. They exhibit altruism, empathy, and a sense of justice, for example. They can plan and execute deliberate deception. They may experience true grief as well.

And now, says a new report in the journal PLOS ONE, we can add jealousy to the mix too. That’s a surprising conclusion for one very big reason. Lead author Christine Harris, of the University of California, San Diego, is a psychologist who usually studies human behavior, and among humans, the conventional wisdom has been that jealousy requires a sense of self-esteem that can be damaged. That’s something animals are unlikely to have.

But it’s also possible, Harris suspected, that all jealousy, human and otherwise, is a more fundamental emotion like fear or lust. If so, it’s presumably a product of evolution, and should exist in some form in species other than our own.

She and her co-author, Caroline Prouvost, set out to test that proposition, and they had some existing data to build on. Several studies, they note, have suggested that infants as young as six months old show evidence of jealousy even though they presumably haven’t developed a sense of self-esteem. In those studies, the babies got upset when their mothers fussed over a realistic-looking doll, but not when the moms ignored them to read a book.

What’s true in barely-developed humans, they suspected, might also be true in highly social animals like dogs—so they replicated the human experiments with canines. They had 36 owners play affectionately with realistic-looking toy dogs while ignoring their own pets. They also had the owners play with Jack-o-Lantern shaped plastic pails, and, finally, had the owners ignore the dogs while reading books.

Sure enough, 78% of the dogs went into a sort of canine snit when their owners played with faux fido: they pushed and tried to squeeze in between owner and interloper, and in some cases even snapped at the phony dog. When the owners played with the pails, by contrast, jealous reactions were triggered in only 42% of the dogs (no word, by the way, on whether the animals thought their owners had lost their minds). And when the owners chose a book over their beloved pets, only 22% of the dogs got upset.

“It’s clearly not just the loss of attention that triggered aggressive behavior,” says Harris. “It’s that the owners were paying attention to another doglike object.”

The finding has impressed some of the most notable figures in the animal behavior field. “This is a landmark study,” wrote Marc Bekoff—professor emeritus of ecology and evolutionary biology at the University of Colorado, Boulder, and the author of the new book Why Dogs Hump and Bees Get Depressed—in an e-mail to Time. “It’s not a matter of if emotions have evolved in animals, but why they evolved as they have.” That question will take a lot more study in multiple species—and Harris plans to do just that. “Horse owners claim their horses display jealousy,” she says, “and the question is open for cats as well.”

What’s more, jealousy is just the beginning of the possible range of emotions animals may experience. “This study reminded me of claims, absent data, that dogs cannot feel guilt or shame,” says Bekoff. “But there’s no reason why they cannot.”

Animal behavior’s official curse word, it turns out, may be on the way out. The more scientists look, the more “anthopomorphism” seems not to be a self-delusional fallacy, but a useful guide to understanding what’s really going on in your pet’s mind.

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