The Australian Terrier originates from many different Terrier breeds. Through the times breeders wanted to develop a small rugged blue and tan terrier that could control vermin, snakes, rabbits and any other smal animals that causeed problems to farmers in the Outback.
Unfortunately no records were kept by early breeders so it is impossible to determine exactly what proportions of the different breeds were used to produce the final result. He has the erect ears of the Cairn, the harsh coat of the Scottie, a Dandie Dinmont top-knot, the length of back could have come from the Skye and the Blue & Tan colour from the Yorkshire. And possibly some Irish Terrier in there too.