I agree with most of what you said, except what I highlighted in blue (another poster changed that line to blue, so I followed suite). I would edit that sentence to say something like The birds bred to a Standard that included tails and muffs became known as Ameraucanas.Araucana and Ameraucana all started from Easter Eggers. When the blue egg layers were first imported into the U.S., they were all called Araucana, and nicknamed Easter Eggers. They were pretty much the same thing we call Easter Eggers, these days. A group of breeders selectively bred for specific traits. They got their birds recognized as Araucana. All the birds that no longer met the new breed standard became known as Ameraucana.
A different group of breeders start selecting for a different set of traits. They got their birds recognized as the Ameraucana breed we know today. Hatcheries and feed stores just never bothered to rename their birds to reflect the change.
It's the Easter Egger that came first. The birds the hatcheries are selling are descended from the originally imported birds, completely unrefined.
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