My tail is particularly beautiful. It is a 37 centimeters long - black all the way down without any vulgar white tip to it, sleek and shining. You can learn a lot from my tail. My main way of greeting Celia from afar - sort of "Hello there" - is to put my tail upright with the tip turned over and towards my head. Human beings with cats usually recognise this signal and some scientist theorize that we cats developed it specially to communicate with them. The idea is that the poor saps couldn't read feline body language easily. So when Felis silvestris Lybica, the African wild cat, decided to domesticate them, my ancestor concluded he needed a better way of saying hello. So he ran up the tail flag, so to speak. Even a really stupid human notices this as a cat steps towards him. I use Tail Up a lot as I like most human beings and most of them, naturally, are impressed and delighted when they see 37 centimetres of tail, with a neat little twist forward, coming towards them. They see it before they see my black whiskers and dazzling golden-green eyes.
Celia, as a good servant should be, pays a lot of attention to my tail. If it starts to lash, she keeps her distance knowing that a disciplinary claw may be next. She also notices it when I am going to pounce on William like a mouse - something he does not appreciate. So she will call out to him to get his attention so that he can lie on his side and protect himself with the lie-on-side claws at the ready posture. Lying down isn't submission. It just clears all four paws for action in this case.
William's tail is much fluffier than mine and some people might think it is prettier. But mine is much longer and snakier.
Tail up!