I'm watching from the anime 'Fruits Basket' [Furuba] I can mouse position first of all because he is shio ride the cow / buffalo. He was a buffalo that although I was quite slow, but the diligent.
Back to the story of Chinese books, the buffalo seems not chapfallen also why the tiny mouse that I can currently many blessings. Create the buffalo, the blessing should be obtained from the body size and body he was clearly more than the mouse. The buffalo eventually challenging both their mouse so that the road in the village get together with people for assessment of village who is big. The rat agree, with the condition he could enlarge the body several times. The buffalo agree, Moreover the rat would want to raise the body of what? Stay where large buffalo everywhere.
Finally, the rat body enlarge some times while the buffalo body still as usual and they just walk in the village. Of course people in the village of breath and sight-point mouse while the "Wow, I had not see the mouse is that Mouse is huge!" Yes yes yes please, also the name of the mouse body is raising a few times. The water buffalo? Yes because there are no changes, the village is considered normal. There is no comment on the buffalo.
The mice eventually to the buffalo, "the village people have commented how the size of myself and they are not any comments about you. Clearly, I am more" and the buffalo are a little slow, he finally confessed defeat.
So that is why mice can be number one position in the shio and why not have a cat in the range shio