Many positive trainers are fond of of saying that an animal can be taught to do anything it is physically and mentally capable of doing. Behaviors are often taught through shaping–using successive approximations towards a final goal. (For instance, a trainer could teach a horse to put it’s nose in a trailer, then put two feet in the trailer, then four feet, then walk to the back of the trailer. Each step approximates the final goal of loading into the trailer.)
Karen Pryor gives some interesting insight on how trainers shape behavior in Lads Before the Wind:
The path to the desired end point can take any direction, there are probably as many ways to shape a given behavior as there are trainers to train it. One trainer’s recipe for a behavior might be quite different from another’s….
Traditional animal trainers rarely are aware of this: they think of their own series of steps as the only possible ones–this is the way you train a horse to bow, this is the way you train a bear to ride a unicycle–and they often guard their shaping recipes jealously and hand them down as family secrets. There are, indeed, knacks and shortcuts in some shaping recipes. The standard way to get a dog to do a back somersault in the air is to teach it to jump straight up, and then swat it across the rump in midair so you turn it upside down before it lands on its feed again. With praise, and food reward, the surprise to the dog is mitigated, and shortly it learns to jump up and fling itself backward to avoid the swat (you need a small, lively dog for this, of course; a fox terrier, not a Labrador retriever.)
A dog back flip is almost always shaped the same way. Watch a dog act with this trick in it, and you can often see the swatting gesture of the trainer’s arm reduced to a cue for the dog’s behavior. That’s the traditional shaping recipe; yet a trainer who didn’t have that recipe could probably train a dog to do a back somersault in a number of other ways.
For many behaviors, there are standard ways to teach that behavior, often because of tradition or simplicity. However, just because there’s one way to teach something, doesn’t mean that’s the right way or the only way. We could teach a horse to walk on a tarp by reinforcing steps towards the tarp. Or, we could give little tugs on the lead rope, encouraging the horse to walk across. Or, we could teach it to follow a target stick across the tarp. Or, we could pressure it from behind with a whip or training stick. Or, we could let the horse alone with the tarp until it investigated the tarp on its own. Or, we could combine two or more of those ways. There are lots of ways to accomplish this goal.
People often approach training looking for specific shaping recipes. They want to know the exact “how-to steps” to do something, which is the information you can find in many training books, DVDs and even clinics. However, more than following a step program of steps, a great trainer understands the laws of shaping. They are able to see the final behavior while considering the place the animal is at now. Then, they can imagine multiple ways to begin to work towards shaping the final goal.
Here’s a great video of someone shaping their dog to blow bubbles in it’s water dish.