The Shetland sheepdog is not just a collie in miniature form, but rather its own breed that has been crossed extensively with the long-haired, or rough, collie. Together they, and other similar breeds, are collectively referred to as collie, but make no mistake; the Sheltie is its own dog that has had many distinct (and extinct) breeds have contributed to its genetic makeup.
Placed in the herding group, Shelties in their modern form are more of a companion and show dog than working animal, however, they still retain many herding instincts and the intelligence associated with the group. It was developed from spitz-type dogs found on the islands of Shetland, which are northeast of England, and that were used for herding the smaller sheep and other livestock that developed there.
The rough collie obviously played a large role in the conformation and appearance of the Sheltie, but in addition to it and the Shetland spitz dog, the King Charles spaniel, Pomeranian, possibly the border collie and the extinct Greenland yakki all played a role in the smaller body and disposition of the breed.
The rough collie factors into the Shetland’s makeup with crosses taking place between the two breeds until ...