Once upon a time there was a breed of chicken called an Araucana.  The Araucanas bore good fruit, in this case a blue egg, and were generally quiet, friendly birds.  However, it had some genetic problems resulting in doa chicks, making it a rare bird.  Eventually, the Araucana found its way to the US where a few people decided they could improve on it and solve its genetic problem and they developed the Ameraucana.  The Ameraucana didn’t have the genetic problems and was easier to breed and became more plentiful.  It too bore good fruit, more blue eggs, and was a quiet, friendly and peaceful bird.  However, because of the slow process of developing a new breed, Araucanas and Ameraucanas were kept on farms with other flocks of chickens of various breeds and Roosters being Roosters, a new hybrid arose in the land.  A hybrid called an Easter Egger.  The Easter Egger also bore good fruit and not just blue eggs but pink and green as well.  It too was friendly, quiet and peaceful.  Now when you decide you want to hang with some chickens you can choose from Araucana, Ameraucana, or Easter Egger.  Or you can mix them up.  In fact a lot of breeders don't know which is which and you might easily end up with an Easter Egger when you thought you had an Ameraucana.  Of course if your hen lays a pink or green egg you will know it's an Easter Egger but if it lays a blue egg you might never know for sure.  But that really isn't going to make much of a difference in the end.  You will still get good fruit from a friendly chicken and when it comes down to it, that's what it's all about because it's by their fruit that you shall know them.