See Spot run. Spot runs fast. Why? Maybe because Spot has a long body, a recent study suggests. 

French physicists studied the relationship between speed and size, from bacteria to the largest mammals, and concluded that body length, not mass, determines an animal’s speed. Their findings were published in the American Journal of Physics on March 29.

The researchers also concluded that animals move 10 body lengths per second, reported Gizmodo Australia.

Studying animals in motion is not new. In ancient times, that study was by observation. Then came photography and its series of images. But today, technology is replacing those now-archaic means. 

Paleontologists at Brown University in Providence, R.I., have developed open-source software that makes X-rays of bones and joints moving inside live animals. The researchers are then able to manipulate the bones and joints, not only to learn how fossilized creatures might have moved, but also to anticipate neurological conditions in today's animals. 

The study was published in Nature on Sept. 1.

Photo credit: © iStock/jean frooms