Synopsis
Book by None
Extrait
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CHAPTER 1
Vision
The typical domestic dog has 20/75 vision, about the same as the typical domestic 90-year-old human. He can't tell a red fire hydrant from a chartreuse one. And he sometimes has trouble finding objects sitting an inch in front of his face.
Then there's the average domestic cat. If he were human, he'd need glasses just to read a billboard. He can't tell a bluebird from a blackbird, and he probably couldn't see a Meow Mix commercial on TV if his acting career depended on it.
But before you start shopping for glasses, consider things from their point of view. Dogs and cats really don't see worse than humans. They see differently--and, in many ways, far better.
"Pets live in a world that we can't even imagine," says Gregory Bogard, D.V.M., a veterinarian in Tomball, Texas. "Our perception of the world is based primarily on our vision. For them, it's just one tool that complements the other senses."
These are important differences to keep in mind when communicating with pets visually. Whether you're teaching them obedience or playing a game of catch, taking advantage of their visual strengths can make a big difference in building a healthy, happy relationship.
HOW DOGS SEE
Ever since their days as pack hunters, dogs have been trackers. To survive in the wild, it was critical for your dog's ancestors to be able to detect motion, no matter how slight or how far away it occurred. And they had to do so in the low light of dawn and dusk, when their prey was out and moving about. Sharp vision wasn't critical, but the ability to see in dim light was.
A dog's corneas are somewhat flatter than those of humans. This allows them to gather more light, but at the expense of visual sharpness. Your dog's world might seem somewhat blurry, but you'd be amazed how well he can see in the dark.
CANINE CAREER AGENCY
NAME: Cap
OCCUPATION: Herder
When one of Alasdair MacRae's barnyard animals gets out of line, he calls on Cap to give it "The Stare."
"He just has a way of looking at animals and making them do whatever he wants," Alasdair says about Cap, a Border collie who works on Alasdair's farm near Charlottesville, Virginia.
A typical day for Cap involves herding sheep and pigs, although he's been known to round up ducks, cats, and even people who go too far afield. Cap's instincts are typical of his breed, which was created to tend flocks along the border region of England and Scotland.
Eyesight plays a key role in Cap's work. Although he's trained to react to whistles and shouts, his superior vision helps him locate wayward animals from amazing distances. Alasdair says that Cap can spot a sheep more than a mile away, run it down, and bring it back in a matter of minutes.
Of course, finding an animal is one thing and getting it to move in the right direction is another. That's where Cap's stare comes in handy. Like most Border collies, Cap has bright, close-set eyes that can absolutely mesmerize livestock. Many Border collies have one brown eye and one blue eye, which enhances their piercing gazes.
"Sheep react to different things about dogs: movement, speed, a little meanness," Alasdair says. "But the eyes can make a very big difference. I think the sheep see that crazy look and figure they'd better do what they're told. I know I would."
Dogs don't see color as well as we do, either. Again, it's a trade-off. Human eyes contain millions of color-sensitive structures called cones. Dogs have some cones, and research has shown that they can distinguish some colors, usually in the blue and violet ranges. But most of their vision comes from structures called rod receptors. Rods are only sensitive to black and white, but they are ultrasensitive to light.
Perhaps the biggest difference between human and canine vision is the width and depth of field. Because their eyes are set farther apart than ours, dogs take in a wider view. They don't need to turn their heads very far to see something moving. The problem with the eyes being so far apart, though, is that they don't share much information. This means that dogs don't have good binocular vision, which limits their ability to see clearly directly in front of them or to judge the distance of a nearby object.
Your dog's vision isn't determined only by nature. Over countless generations, breeders have sought to improve different aspects of vision. In some breeds, for example, long-distance vision is prized, which is why herding dogs, such as sheepdogs, may be able to see hand signals from a human more than a half-mile away. Terriers, on the other hand, were bred to have their eyes closer together. This gives them a narrower field of vision, perfect for chasing--and catching--small, burrow-dwelling animals. And many dogs, such as Afghans, have been bred to have their eyes very close together, giving them a loving, almost humanlike appearance.
HOW CATS SEE
Like dogs, cats are renowned for their hunting skills. But unlike dogs, who depend on speed and stamina to catch their prey, cats use more of a stalking, silent approach and have developed the necessary vision to help them do it.
Cats hunt small animals and £ce from close range, so they need better focusing skills than dogs. This is why their eyes are placed much closer together. Their binocular vision is terrific, almost as good as that of humans. Binocular vision gives them decent depth of field, which means that they don't £ce 7 feet for a mouse that is 8 feet away. Dogs, who evolved to hunt prey larger than themselves, don't need that kind of precision.
Cats have very large eyes relative to the size of their heads, which is part of what makes them so attractive to humans. More important, at least from a predator's point of view, is that their big eyes admit lots of light at night. "The animals that cats hunt come out at night, so they need to capture every little bit of light possible," says Gwen Bohnenkamp, owner of Perfect Paws, a dog and cat training center in the San Francisco Bay area, and author of From the Cat's Point of View.
To enhance their nighttime vision even more, cats' retinas are coated with a reflective layer called the tapetum fibrosum, which boosts the amount of light they take in. (Reflections from this layer are what cause cats' eyes to glow in passing headlights.) In fact, cats can see in one-sixth of the light that humans need. Finally, cats have a wider field of view than most people.
As always, along with these superior skills come some trade-offs. Cats have poor color vision. And they don't see terribly well in bright light because their eyes are designed to see best in the dark. During the day, your cat's pupils narrow to slits to keep out the light.
Most breeds of cats have similar types of vision. The only exception is the Siamese cat, which has little, if any, binocular vision. When hunting, Siamese cats can only guess at the exact distance of their prey.
SEEING EYE-TO-EYE WITH YOUR PETS
Since humans and pets see in different ways, they must find some middle ground in order to communicate effectively with eyesight. Dogs and cats use their other senses to complement vision to a greater degree than humans do, says Dr. Bogard. While eyesight is our best sense, smell is equally or more important to dogs. And both cats and dogs use hearing at least as much as vision. So when you're communicating with your pets, you'll have the best results when you combine visual cues and signals with cues that incorporate their other senses.
Since cats don't focus well on objects that are very close or too far away, it's best to stay within their optimal visual range when you're trying to communicate, Bohnenkamp says. If you're too far away, your cat will barely see you, and if you're too close, it will make him a little uncomfortable because he won't be able to read the subtle clues of facial expression and body language, she explains.
Dogs don't focus especially well at any distance, so it's less important where you stand. But it's usually a good idea to stay a few feet away when teaching obedience or giving discipline, says Andy Bunn, a trainer in Charlotte, North Carolina. Getting too close and going nose-to-nose with dogs is often intimidating to them because most dogs are a lot smaller than we are. A large human face looming inches away, combined with a stern voice, will cause some dogs to cower and others to become aggressive, he says. In either case, your dog will lose his concentration and will be less likely to respond to whatever it is you're trying to say.
You always want your pets to look you in the eye when you're trying to get their attention, but you don't want to turn it into a staring contest. "If you want to get into a fight with a dog you don't know, just look him square in the eye," Dr. Bogard says. The reason for this is that dogs originally lived in packs, and only the leader of the pack is permitted to stare at the others. A stare from a "lesser" dog may be perceived as a challenge, he explains.
The Appearance of Fun
There's an old saying among anglers: "Pretty-colored lures don't catch more fish, but they sure catch more fishermen."
It's the same with cats and their owners. Pet supply stores are packed with colorful cat toys--neon orange balls, lime green mice, and fuchsia- feathered mobiles. These bright-looking toys catch the attention of plenty of cat owners, but the cats couldn't care less. All they want is a toy that reminds them of prey.
"If you really want to bond with your cat, pick a toy that has lots of motion," says Gwen Bohnenkamp, owner of Perfect Paws, a dog and cat training center in the San Francisco Bay area, and author of From the Cat's Point of View. "Cats are geared to spotting and £cing on things that move, and the color doesn't make a bit of difference." They also respond to shapes, so toys that resemble mice, voles, chipmunks, birds, or other animals make the best gifts.
This doesn't mean that you have to throw out that hot pink, squeaky rubber toad just because it's brighter than a 200-watt bulb. If it's the right shape and moves the right way, your cat will still enjoy it. "Besides, colors are good for at least one thing," Bohnenkamp says. "They make it easier for you to find the toy when it falls behind the sofa."
If you run across an unfamiliar dog and are worried about his intentions, don't try to intimidate him by making prolonged eye contact. It's better to turn sideways and look at him out of the corner of your eye. Among dogs, this signals peaceable intentions and could save you from a chomp on the leg, Bunn says.
With family pets, usually it's fine to look them in the eye. For one thing, you're supposed to be the acknowledged leader in the family, and this won't be perceived as a threat. Also, says Bunn, many dogs enjoy calm, up-close eye contact with their owners, and there's no harm in it at all as long as everyone knows his role. The rules change, however, if your dog is sometimes aggressive. In that case, you'll want to avoid prolonged eye contact until you can get some advice from your veterinarian or a professional trainer.
Eye contact is a mixed bag with cats. Sometimes a cat will view it as a threat, sometimes as affection. "It varies widely from cat to cat, so I'm not sure there's any basic rule," Bohnenkamp says. One exception to this is when you're disciplining your cat, in which case eye contact could be a problem, she adds. For example, staring and yelling at your cat when he jumps on the counter will only make him fearful, and he probably won't understand why you're angry. A better approach is to stand where he can't see you and give him a quick spray with a water pistol. Your cat will learn that jumping on the counter results in getting wet, but the message won't be delivered with the type of threatening stare that could make him distrust you in the future.
THE RIGHT BODY LANGUAGE
Because they see things differently, dogs and cats don't respond in the same way to exuberant body language, so you have to tailor it to each pet. Dogs notice movement and may get excited by it. So when you're "talking" with your dog, don't hesitate to wave your arms, jump up and down, and generally make a fool of yourself. The same is true when you're teaching your dog to respond to hand signals. You'll want to exaggerate them at first so that he can clearly understand what you're trying to communicate, Dr. Bogard says.
Try any slapstick stuff on a cat, however, and he'll probably look at you like you've had one too many cups of coffee--if he looks at you at all. Cats don't respond well to dramatic hand and body gestures. "It's like they're saying, 'I can see you, already. Let's have a little dignity here,' " Bohnenkamp says. A better way to get your cat's attention is with subtle movements--a slight wiggle or twitch of a favorite toy, for example. He'll get your meaning right away. Whether or not he'll play, however, depends entirely on his mood. "If he wants to respond to the movement, he will," she says.
PETS VS. PEOPLE
Comparing Fields of View
Even though dogs and cats don't see things as sharply as humans do, they have a wider field of view--which is why they can detect movement off to the sides without turning their heads. Here's how we measure up.
It's also important to be honest with your body language. Cats are absolute experts at picking up visual clues. "It's very tough to fool cats by saying one thing while you're feeling something else," Bohnenkamp says. "They can pick up on the smallest of details: how you're standing, what your posture is like, the look on your face. All the sweet talk in the world isn't going to work if your cat decides you're up to no good."
When it's time to take him to the vet, for example, act like you're going to the vet, Bohnenkamp says. Bend over, pick him up, and get going. All the smiley-faced, I-love-you-snookums, now-get-in-the-box stuff will just be wasted. Worse, it will probably make your cat more nervous because he'll know there's some serious deception going on.
Fun with Frisbees
Tired of the tuggy sock? Bored with the Booda Bones? A great way to energize your relationship with your dog is to teach him a new game that takes advantage of his natural vision skills: Frisbee catching.
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