In the 12,000 years since dogs emerged from the wilderness to join humanity, our companions have never failed to amaze us. Their intelligence, courage, adaptability and physical abilities have reached legendary proportions in literature and the media.
But truth is always more amazing than fiction. Here, we've collected only facts about dogs for you to chew on, from their accomplishments to their remarkable abilities. The next time Scruffy tears up your favorite pair of slippers, consider what his forebears have accomplished. (And realize that maybe you just don't understand your dog's delicate genius.)
Most people know that a Russian mongrel named Laika made the first "manned" space flight (in 1957). But few people know how many dogs actually went into space and how many made it back. In all, 13 dogs flew on Russian spacecraft; 5 never made it back, including Laika.
Of all the dogs that made space flights, only Laika was actually sent aloft with the knowledge that there was no way she would ever be recovered. The dog's plight captured the hearts of millions around the world as her life support systems wound down. The American press dubbed the dog "Muttnik." In 1997, Russia dedicated a memorial to the fallen dog hero.
A greyhound can run up to 45 miles an hour in a short dash. That's just 15 miles an hour slower than the speed of the cheetah, the fastest animal on earth. (A cheetah can run 60 miles an hour. Here's an interesting fact about cheetahs: they don't stalk like cats; they run down their prey like dogs.)
The vitals of a canine are different from those of his human counterpart. A dog's normal temperature is between 100.2 and 102.8 degrees Fahrenheit. The dog takes between 10 and 30 breaths each minute, depending on his level of activity.
In a dog, the nose knows more quickly than the other senses. While humans have to be content with a mere 5 million to 20 million scent-sensitive cells, most dogs boast between 120 million and 200 million of these cells. Bloodhounds have the best sniffers of all – more than 300 million scent cells line the nostrils of these dogs.
Ever wonder how dogs can tell one dog or person from another? Every odor has a distinctive "shape" that excites scent cells in a specific way. Because dogs have so many more of these cells, they can identify many different smells.
Right behind a dog's nose sense is his sense of hearing. Again, your dog's hearing abilities put yours to shame. Human beings can hear sound waves of up to 20,000 cycles per second (sound waves). A dog can hear up to 100,000 cycles per second. Filters within the ear enable your dog to distinguish the far-away sound of your car. This is why he pricks his ears up while the rest of your family is unaware of your imminent arrival.
Although a dog has a vastly superior nose, he has decidedly inferior taste buds. Compared to a person, who has almost 10,000 taste buds, a dog makes do with only a few hundred. In other words, dogs cannot tell many tastes apart. The enjoyment of food comes primarily from the aroma. In addition, a dog is genetically wired to gorge, especially if there's another dog around, because in the wild dogs never knew when their next meal was coming.
One taste many dogs do enjoy is that of sugar, and many dogs have a "sweet tooth." This may be because sweetness signals that a plant is ripe and at its highest in nutritional value. However, this taste can get them into trouble if they eat chocolate or lap up antifreeze, which has a sweet taste. Both are poisonous – antifreeze is especially dangerous.
The oldest recognized breed of dog in the world is believed to be the Saluki, which was the royal dog of Egypt (mummified dogs have been found in royal tombs). The breed was recognized as far back as 329 B.C., when Alexander the Great invaded India.
Your dog's heart is similar to your own. It is divided into four chambers: the right atrium and ventricle channel blood to the lungs to get oxygen while the left atrium and ventricle pump the blood to the body. But unlike you, your dog has very little chance of suffering a heart attack, stroke or atherosclerosis.
Unfortunately, dogs do suffer from other common ailments found in people, such as diabetes and cancer. One common disorder is congestive heart failure – which means the heart muscle cannot pump blood efficiently. (Heart failure is not the same thing as a heart attack, in which the heart muscle begins to die because of obstruction of circulation to the area) Congestive heart failure is in the top five illnesses for which veterinary treatment is required.
Dogs often get conjunctivitis – otherwise known as "pink eye" – and their owners worry that the infection can be passed on to the human family members. Relax. The bacteria that causes conjunctivitis in dogs is not the same as the one that affects humans.
People sometimes consider their dogs to be almost human. That's fine when it comes to showering affection and attention on your pet, but dangerous if you try to give him human medication. Dogs should never be given over-the-counter medication, unless specifically prescribed by a veterinarian. For instance, if aspirin is given incorrectly it can cause stomach bleeding in dogs.
North America has the highest population of dogs in the world. The Chihuahua is believed to be the oldest breed of dog native to the North America. It hails from the Mexican region of the same name.