As late as the 1980s, most scientists thought humans were the only species who displayed “lateralized behavior,” meaning they strongly preferred either their left or right hand. But since then, more and more scientific research showed that “handedness” isn’t a uniquely human trait after all.  

Many published studies now describe in quantitative detail how mammals, birds and even fish have a bias towards one side of their bodies. Most pet owners could have told scientists that long ago.

Certainly in our family over the years we’ve noticed that each of our dogs and cats has displayed a strong preference for using one paw over the other. You’ve probably observed this with your own pets.

A fish will always choose one direction to turn to avoid a predator. A parrot will use a specific foot to pick up interesting items. A frog will consistently grab food flying into his line of vision on one side faster than from the other.

With dogs, you’ll see they usually favor one particular front paw to step off with, go up or down stairs, whap a playmate with, or put on your knee to get attention. You may notice that your dog prefers to lay on one particular side, or that when she wags her tail, she always begins the wag on one specific side.    

You can test if your dog is right- or left-pawed by giving him a Kong filled with luscious treats. Put it a several feet away from him so it’s not near either one of his paws and observe which paw he uses most to hold down or manipulate the Kong, and which paw is on top of the other. Also watch him run outside or go up or down stairs, to see which foot he starts off with.

It seems that in most studies, female dogs preferred their right paws and males their left. There were also a few ambidextrous dogs as well.   

Scientific studies show that cats also display a strong preference for a left or right paw. In their case, it seems that complex tasks, such as fishing tasty tidbits out of a narrow container, caused the cats studied to use one paw consistently. While chasing toys on the ground or batting them in the air, they tended to be more ambidextrous. In some studies the males tended to be the “lefties.”    

In our family, we’ve noticed that when our cats jump onto furniture, they launch themselves with their favored paw. When they’re stalking, the first step is made by the dominant paw. You can see an example of this with this video of a running cheetah in slow motion.

We have discussions about handedness every time we clip our cats’ nails, because each cat invariably gets mightily upset when we clip the nails on one particular front paw. On two of our cats, it’s the front right paw. On the other four, it’s the left paw. They’re comparatively calm during nail clipping until we get to the favored paw, and the drama begins.

It’s intriguing to me – and I hope to you – to watch our pets in action. Perhaps we can turn our lefties into Arnold Palmer or Sandy Koufax – and they can support us for a change.