Study Leads to Better Understanding of the Dog-Paddle
It has long been believed that dogs do not actually swim, but instead trot to propel them through water. A trot means that the front paw rises and falls in sync with the opposite hind paw. After looking at six breeds of dogs as they propelled through water, however, it looks more like they are running. This preliminary discovery was made by Frank Fish of West Chester University in Pennsylvania, before being presented on January 5 at the annual meeting of the Society for Integrative and Comparative Biology and reported in Science News.
Fish explained that the diagonally opposite paws were not moved in synchrony, but instead followed a more complex pattern that is similar to a run. What Fish and his colleague found amazing was the remarkable consistency of the gait between all types and sizes of breeds observed. Fish wanted to study the way dogs swim, in order to look closer at the way they might have been pressured during evolutionary history to go from struggling swimmers to the more efficient swimmers they are today.
Eight dogs were used, including a Labrador retriever, German shepherd, Fish’s Nova Scotia duck tolling retriever and a Yorkshire terrier. The dogs swam in a swimming pool or veterinary water-therapy tanks, while Fish filmed their legs from his position under the water. Each dog swam by, extending its legs, while making the power stroke of sweeping down and back. When they begin to bring that leg forward again, they reduce the amount of drag in the water by slowing down the motion of the leg and tucking it closer to the body.