Margaret Cho

Border collies predate the British Kennel Club. They've been bred consistently for 100 years. They're the last working dogs in the world, with some minor exceptions. Bench shows, dog shows have ruined the other breeds, like the hunting dogs. Border collies are peasant dogs, and that's protected them.

The historical novelist has to consider what has actually happened, while the SF writer is dealing in possibilities, but they are both in the business of imagining a world unlike our own and yet connected to it.