That's fascinating, especially this bit at the end: The gene for chondrodysplasia in various short-legged breeds has been confirmed to trace back to a single a

That's fascinating, especially this bit at the end: The gene for chondrodysplasia in various short-legged breeds has been confirmed to trace back to a single ancestral mutation [presumably from Egypt, as the Egyptians since short legged dogs had been found in Egyptian households dating back thousands of years. Egypt was also thousands of years in advance of modern pet keeping by quasi-domesticating Ball Pythons.