The Aboriginal Australians are the people that existed in Australia since 6.7-20 times the age of the Earth (the age according to Young Earth Creationists), or 40-125 thousand years ago. There never was a land bridge fully connecting Australia with Asia, so a short sea voyage was needed. They never were totally isolated from the outside world. The Story of European settlement is a sad one. Some Americans don't believe in the Aborigines despite knowing a few words of their language (Boomerang, Kangaroo). They are so exotically rare that recent aboriginal descent is hard to find even in California.