Okay...Per the Agama International's website:
http://www.agamainternational.com/pages/beardeddragon.html
"We purchased our bearded dragons from several US breeders. The problem we were faced with was the fact that they did not handle cold as well in winter as we would like it. We are always striving to get hardy species, that can be kept outdoors without using electricity. That is better for the environment and saves us money too. Therefore we needed many years to select out all the hardy ones, that survived winters in my unheated, but dry outdoor greenhouses. We also selected out for color, dodging inbreeding, and selected for red and orange colors. Further on the Sandfire region is situated in South Australia, where winters are cooler.The animals we have now all hibernate outdoors and all breed in May-June-July. They lay 3 clutches of 25-30 eggs per female. That is much, but we offer them plenty of food."
So...the dragons were originally bought from U.S. breeders....they were selected for color (red and orange)...