These little fellows are so small and charming but monster sized personalities. They are very independent and demand attention. They are great pets for apartment dwellers because the don't make much noise. When you have several pairs you can often hear them bickering. It is quite comical because while they are venting their displeasure they are spinning around getting fluffed up. There are many varieties, green rump, Pastel, Blue mutation, American white, and American yellow. The difference between male and female is easily determined. The male has royal blue in the vicinity of the ears and on the wings. The female is not as pronounced.