Shetland Sheepdogs, more commonly known as shelties, are often confused with collies and are sometimes referred to as "miniature collies". However, the Sheltie and the Collie are two distinct breeds. And, while they do look very much alike, there are quite a few differences.
Shelties are quite a bit smaller than collies. Shelties weigh about 15-25 pounds, compared to the full sized collie, which weighs in at between 40-66 pounds and stands as much as 25 inches tall.
Though the sheltie looks very much like a smaller version of the rough coated collie, the sheltie does not come in two varieties of coat as the collie does. In addition to the rough coated collie, which is very similar in appearance to the sheltie, there are also smooth coated collies, which have very short coats of only about 1 inch in length.
Collies were developed in Scotland in the 17th century as sheep herding dogs. It was their task to keep the herd of sheep together in a fold. Shelties, on the other hand, were developed in the Shetland Islands in the 1800s, and while they were also bred for herding, their task was quite different. Shelties were used on farms to keep the sheep away from fields where they might be tempted to graze on growing vegetables. The reason that collies and shelties are so similar in appearance is because the collie breed, which has been around longer than the sheltie, was one of the breeds used to create the sheltie.
Collies are very docile dogs that possess an air of elegance and refinement in their demeanor. They are quite calm, especially indoors, and may seem somewhat aloof around strangers. Shelties, on the other hand, are very lively and playful. They can have a goofiness about them that collies wouldn't dare to possess. They are more active by nature than collies and friendlier to strangers. Both are very good with children and both are very sweet and gentle dogs. In addition, both are very intelligent and highly trainable. If you're looking for a playmate for your children, a sheltie might be a better choice than a collie. Conversely, if you're looking for a companion for an adult who is not especially active, a collie might be a better choice.
Shelties may seem more suited to apartment life than collies because of their size, but this is not necessarily the case. Though shelties are smaller, they are also more active, so they may need more exercise than the collie, who is quite happy with a walk each day.
Both collies and shelties are excellent choices as family pets. They are similar in personality because of their sweet gentle nature and their willingness to please their owners. Both need early obedience training and both are intelligent enough to learn any task you choose for them.