Is the tailless look enough to guess Manx heritage, or do bobtailed mixes confuse things?

The tailless look alone is a gamble if you're trying to peg a cat as a Manx. I've seen plenty of bobtailed mixes-especially from random barn cat lineages-that carry a shortened tail from a different gene mutation, not the specific Manx one. The Manx gene is dominant and linked to that complete rump of missing tail, but it also comes with a distinct body type: a rounded, compact build, a noticeably longer back, and a bit of a hop in the hind legs like a rabbit.

What most people miss is the feel of the spine. A true Manx has a hollow or dimpled area at the tail base where the last vertebrae are absent, not just a stump. Bobtailed mixes usually have a rigid, bony nub that's still connected to the spine. I've had folks show me a cat with a three-inch tail and insist it's a Manx, but it was clearly just a random mutation from a mixed litter. If you're guessing heritage, look for the whole package-the body, the gait, and that tail socket-not just a missing tail.