The Genetics of Behavior: What Color is Your Dog?

Jim Ha, PhD, CAAB

Behavior has many causes: this is a general statement that many people believe is true, and it often causes people to extend the conclusion to one that suggests that we can never understand behavior, that it will always remain a black-box mystery. But of course, as professional animal behaviorists, academic or clinical, some of us have set ourselves the goal of understanding the causes of, and therefore the modification of, just that behavior that seems so complex.

Of course, as is so often true, the answer that we see depends on the focus that we bring to the question. To a professional animal behaviorist (let’s use the more modern name for one who studies animal behavior: an ethologist), the answer for the cause for a behavior depends on the level at which you want an answer. Let’s start simple today, a higher, broader level of analysis. For an ethologist, behavior has two possible causes, and is most often caused by an interaction between these two: genes and the environment. This is the old nature/nurture controversy that we still occasionally see raise its head, but as we well know now, all behavior is, at some level, a result of both genetic predispositions and the effects of the environment. And when we say ‘effects of the environment’, we really mean learning: all of the behavior modification that has occurred through the learning that an animal has experienced throughout its lifetime. We know now, for instance, that for all animals, there are four types or forms of learning, and that every modification of behavior gained throughout the lifetime of an animal has happened through one of these four mechanisms. But the four forms of all learning is a topic for another blog: today I want to mention some new literature that once again points to the role of genetics in the behavior of our canine companions, and of course, suggests a similar role for genetics in the behavior of cats, parrots and even ourselves.

What color is your dog? The color of your dog can tell you something about the genetic predispositions for its behavior. Now, let’s be careful: I phrased that sentence with some thought. The color of your dog tells you something about predispositions for behavior, not the behavior of a specific animal. Why? Because, as we said above, the behavior of a specific animal is determined by both its genetic predispositions and the effects of its lifetime environment. This is why the extensive history that we take at each one of our clinical appointments are so important: that history, and every part of it, has had an influence on your pet. But likewise, the scientific evidence is quite clear that genetics is important too.

So what about color? Well, we all agree that color is genetically determined by genetics (not entirely, but largely) and we know that almost all genes control more than a single characteristic (in fact, each gene controls many characteristics), so the color of your dog can tell you something about its genetic code, and therefore, something about its genetic predispositions. Really? Yup, for instance, researchers just this past year showed quite clearly that, in Labradors, occurrence of problem behaviors like barking, chewing, and digging, were related to coat color: gold dogs showed significantly higher levels of these behaviors, even after numerous environmental factors were removed. This supports a 2001 study, in which researchers at Cornell University’s Veterinary Hospital showed that chocolate-colored Labradors were less likely to present with behavior problems than other Labradors, and that gold/yellow Labradors were significantly more likely to be reported with aggression problems.

How about other breeds? Well, there is very little research in applied animal behavior (anyone looking for a philanthropic opportunity?), but a study in 1996 showed that red or golden English cocker spaniels were more likely to show aggressive behavior than black ones. Interesting, huh?

And now, with the completion of the Dog Genome Project, we have a complete map of the domestic dog DNA. With this tool, we are rapidly gaining more information about the role of genetics, and genetic interaction with learning, in determining the cause of our dogs’ behavior.