What is the difference between a horse and other quadrupeds when running?

There is a special phenomenon when horses run, that is, their hooves always touch the ground. Horse racing can be divided into jogging and running. When jogging, your feet cross the ground, that is, right front, left back, left front and right back, to achieve balance; When running fast, one foot always touches the ground, which is a unique phenomenon of "one-three alternation" Other quadrupeds may have their own characteristics, but none of them have this phenomenon.

The following is a real event for your reference: whether a horse always touches the ground when running, from which the movie was born.

1872 One day, in a hotel in California, Stanford and Cohen had an argument about whether the hoof touched the ground when the horse was running. Stanford thinks that a horse runs so fast that its hoof should fly at the moment of jumping, but Cohen thinks that if a horse's hoof can fly, won't it become a frog? There should always be a hoof on the ground. The two men were at loggerheads and flushed, and no one could convince anyone.

So the two invited the British photographer McBride to be the referee. McBride couldn't figure it out, but the photographer was a photographer after all and still had some ideas. He put 24 cameras at the same distance along a runway, aiming at the runway; On the other side of the runway, 24 stakes were nailed to corresponding points, and thin wires were tied to the stakes, which passed through the runway and connected to the camera shutter.

Everything is ready. Mcbride let a horse run from one end of the runway to the other. When the horse ran, it tripped over 24 thin threads in turn, and the camera took 24 photos in a row. There is little difference between two adjacent photos. The photo shows that the horse always lands when running, and Cohen wins.