Well, I thought it was just a legend, but it turns out to be true. Don’t believe me? Well, check out below.
First of all, here is how it works (according to Wikipedia):
Fleas typically live only for a few months and are not trained. Fleas are observed to see if they have a predisposition for jumping or walking. Once sorted, they are harnessed by carefully wrapping a thin gold wire around their neck. Once in the harness, the fleas usually stay in it for life. The harnesses are attached to the props and the strong legs of the flea allow them to move objects significantly larger than themselves. Jumping fleas are used for kicking small lightweight balls. They are carefully given a ball; when they try to jump away (which is not possible because of the harness), they shoot the ball instead. Running fleas can pull small carts and vehicles or rotate a Ferris wheel.