By Gary Koehler


Mark Lasnek

Ever since Ivan Pavlov used dogs during the 1890s to explore classical conditioning, the sky has been the limit for those who want to learn more about canine biology and behavior. Because of their popularity as pets, dogs may be the most studied animals on earth.

Most of us have probably done at least some delving into what makes our retrievers tick. We can't help it. The subject is endlessly fascinating, and the more we know about our dogs, the easier it is to train and live with them. Although many questions remain, science continues to provide new insights into the lives of our four-legged hunting partners.

Here's a look at several interesting facts that explain how dogs perceive the world and why they behave the way they do.

1. Sight

Contrary to popular opinion, dogs are not color blind. The old notion that they can see only black and white is incorrect. The canine color field may be limited in comparison to ours, but dogs can perceive gradations of yellow, blue, and gray. They can't, however, distinguish red, green, and orange colors, as humans do. That's because the human eye contains three types of cones, while the canine eye has only two. As predators, however, dogs are equipped with superior night vision and are also much more capable of tracking motion than we are.

2. Smell

As discussed in a previous column, a dog's scenting ability is truly remarkable. The noses of some breeds have more than 200 million scent receptors, which is about 40 times the number humans have. This isn't surprising considering that a dog also dedicates about 40 times more of its brain to the process of smelling than we do. No wonder our retrievers continually amaze us when they locate fallen waterfowl in heavy cover.

3. Hearing

Dogs generally have a much better hearing range than humans. A dog's ears include at least 18 muscles, while ours have only nine. Dogs can therefore rotate and tilt their ears, which allows them to more easily locate the exact source of a sound. In addition, they perceive almost twice the frequencies we do. This explains why dogs can hear high-frequency whistles that are soundless to us. If your retriever is afraid of your lawn mower or weed whacker, it's probably because the dog is bothered by the sound, not the motion. Thunderstorms can also be troublesome.

4. Mood Detection

Your retriever can read your mood just by looking at your facial expressions and body language. Over time, he or she will learn to sense when you are happy, sad, and angry. The flipside of this is our tendency to attribute human emotions to dogs. For example, when you chastise your retriever for digging in the yard, he may put his head down or look away. The dog is probably reacting more to your tone and body language than out of a sense of guilt or shame.

5. Intelligence

Mental sharpness varies greatly from breed to breed, and even from dog to dog. In fact, pups from the same litter may exhibit different learning abilities. Some dogs are inherently smarter than others. Studies have shown that intelligent dogs can learn the meaning of up to 250 words. Average dogs are capable of understanding about 150 words.

6. Thermoregulation

The normal body temperature for a dog ranges from 100deg;F to 102.5deg;F. Fur insulates a retriever's body in cold weather and helps slow heat absorption in warm weather. Although dogs do sweat through their paw pads and nose, they regulate body temperature primarily by panting. Always keep in mind that the risk of hypothermia and heat stroke are very real when your retriever is outdoors in extreme conditions.

7. Dreams

The fact that dogs can dream shouldn't come as a surprise to retriever owners who have seen their dogs whimper, twitch, and move around in their sleep. Determining what dogs actually dream about is a more complicated matter, but recent research seems to indicate that, like people, they tend to recall memories of events they experienced while awake. This means that retrievers are probably "fetching" mallards in perhaps their most lucid dreams.