Have you ever wondered why your toy poodle
follows you around the house like a shadow? Or why your beagle can't resist going over to your neighbor's backyard and exploring? Or why it seems that your golden retriever
could play fetch with a stick for hours on end? You may not have encouraged these behaviors. In fact, you may even have tried to discourage them. But somehow they persist: Your dog naturally seems to have certain personality traits. The reason is selective breeding.
Simply put, this means breeding an animal for a certain purpose or trait. Suppose, for example, you have a litter of puppies
and you need dogs to herd sheep. "The first step would be to take that litter and without any training whatsoever, put them around the sheep and see which dog pays the most attention to the sheep," explains Rolan Tripp, a veterinarian in La Mirada, Calif., and an affiliate professor of applied animal behavior at Colorado State Veterinary School. "The second step would be to breed that dog to another with the same natural talent." Chances are, the next generation would also have these tendencies.
Animals are also selectively bred for physical characteristics. For example, you might breed only the biggest dogs to the biggest dogs, or only longest-haired dogs to longest-haired dogs. "You would start by breeding two animals together that have a certain look," says Sarah Wilson, pet behavior consultant and co-author of Paws to Consider
(published by Warner in 1999). "Of their offspring, you select the puppy or kitten that is closest to your goal. Then you would breed that animal to another with similar characteristics. With each generation, you'll have less and less variation."Your Dog's Heritage
Traditionally, dogs were bred primarily for certain functions, such as hunting, retrieving or herding. Bernese mountain dogs, with their thick coats and strong limbs, were bred to guard herds and flocks in the mountains. Bloodhounds and basset hounds, with their natural talent for following a scent, were bred for scent-tracking jobs. Greyhounds, with their slim bodies and long legs, were capable of great speed and thus were bred for racing. Rottweilers, with their strong bodies and naturally assertive personalities, were bred as guard dogs.
The key to understanding selective breeding in dogs, Tripp says, is to look at the instincts of dogs' ancestors, wolves. "During a hunt, certain wolves specialized in different aspects of the hunt," he explains. "Through selective breeding, dogs that performed only certain aspects of the hunting ritual were derived. The best smellers were bred together, those with the best sight were bred together, those that ran the fastest were bred together, and this resulted in distinct dog breeds
Sighthounds are best at pursuing prey animals by sight. Scent hounds, such as bloodhounds, lead the hunt by sense of smell. Pointers and setters select and indicate specific targets. Shepherd dogs herd sheep using instinctive hunting instincts. Terriers dig up prey animals that attempt to escape underground. Retrievers specialize in retrieving and bringing "prey" back to the den. Each breed has a specific job to do, and each has had its innate level of aggression inhibited.
Certain wolves, however, were responsible for the actual killing of the prey animals, and these characteristics are the ancestors of dogs such as Rottweilers, chows, pit bulls and akitas. These breeds are genetically programmed for aggression – which may be just what is needed for a police dog or guard dog.
Of course, many of these breeds have been in existence for hundreds or thousands of years, as is the case with bloodhounds, greyhounds and Rottweilers. Over the last century or two, there has been a lot of fine-tuning, though, especially for physical appearance. "A hundred years ago, dogs were bred primarily for performance, but today they are being bred more for their appearance," says Dr. Karen Overall, director of the Animal Behavior Clinic at the University of Pennsylvania's School of Veterinary Medicine. "Today we're breeding mostly for size and shape: we've shrunk dogs, we've made them bald, we've made them hairier, we've made them fuzzier, or we've made them giants."What This Means for You
As a pet owner, it's important to understand your dog's roots. "If you know what the tendencies are for the breed, you'll be able to anticipate what type of behavior problems you may have to deal with down the road," Wilson says. For example, if you've got kids and you're considering getting a border collie, a breed with a tendency to "herd" children, you'll know to watch for these tendencies in the dog and be able to get control of the problem early on.
Knowing what your dog naturally likes to do will also help you play with him. If you've got a Dalmatian – a dog that was bred for running 30 miles a day as a carriage dog – you might take him out jogging with you. If you've got a Labrador retriever, a game of fetch is an obvious choice. "But if the dog isn't a retriever, fetching isn't in their repertoire, and you may just get frustrated trying to teach the dog to fetch," Overall says.
Keep in mind, though, that each individual animal is different. "Don't be surprised if your dog doesn't fit every single breed characteristic that you've heard about," Wilson says. "You may well get a Labrador that does not like to retrieve or a terrier who watches a squirrel go by without chasing after it – but the likelihood of encountering such indifference is less with either of these breeds than if you had a breed that didn't have such interests in the first place."
In addition to genetics, two other factors that influence your dog's personality are his experiences during his socialization period as a puppy, and what happens in his environment as an adult dog. "Obviously, you can't change your pet's genes," Tripp says, "but even if you have a dog that tends is genetically programmed to be very aggressive, if you handle him correctly during puppyhood, and steer and shape his personality, he may still turn into a reasonably good pet."