Sometime in the past, the Jade Emperor (Lord of Heaven) was contemplating the chaos which reigned among the animals of the earth. Each of the animals had proclaimed themselves that they were the most virtuous and unique on earth.
The Emperor thought that chaos comes only from order and there was a way that needed to restore order. He then thought of holding a race and then the winners would be declared as the First of the Earthly Creatures.
He chose a day and all the animals assembled to the starting point, each thinking they would be the winner. The Jade Emperor explained the contest rules to each animal saying that there would be a time limit and the first twelve animals would be the heavenly stems, a lasting position in the divine order of things.
All the creatures were running at their best. The horse was in the lead, galloped over hills and was thinking of being victorious. He then came across a stream and with his rushing momentum could not stop so he fell in the stream. The ox, behind the horse moved through the stream with ease since the ox was used to plowing though many rice paddies in his time. The ox then thought the victory would be his.
As the ox approached the finish line, a tiny creature leaped from the ox's ear and scurried to the finish line to be first. It was the rat! The ox came in next (angry that the rat rode on his back). The other contestants began to straggle in. The tiger, a ball of wet fur, came in next. The rabbit, dragon, snake, ram, horse, monkey, rooster, dog and pig all followed thereafter, and thus became the 12 zodiac signs which the Chinese have consulted through the years.