[muawiyah]

Splits and fusions within the realm of chromosomes though technically a sort of "mutation", do not require any gene mutations ~ which means that at the point where you started talking about "mutations" you steered right off the cliff into a pile of macacca.

[Rurudyne]

Not precisely true. Take the instance of the Petawalksi's horse and the domestic horse, for example.

The fusion of on two base pairs from the one seems to have occurred in historic times, and the two are compatible with few fertility problems. A mating results in an animal with 65C where one domestic horse chromosome is the same as two in the wild pony.

As a result of this fusion the domestic horse has become similar enough to an older branch of the family, the donkey, to make it possible to cross breed (producing an animal with 63C); however, these are normally sterile because of differences between the genes.

The point that should be made is that even if a fusion is an otherwise harmless mutation (fissions would appear to be more problematic) there is still no multiplicity of canids with similar sexual function and behavioral tendencies between the canines and the vulpines. At least not as there is for the extended family that includes horses.

Given the range of these species, as well as the success of the basic design––even their response to domestication is similar given one Russian experiment––it would seem inexplicable that there are just those with 78C or 34C.

Again, there is no good explanation for this as far as I know.