look up "sampson fox" online. Its a RARE genetic mutation(like birth defect) that sometimes affects normal red foxes. It is very uncommon, but the genetic flaw prevents the fox from being able to grow fur. Sometimes they are completely furless, and sometimes they just have fur patches or a ridge down the back etc. Due to their furless condition, they are forced to hunt during the day to keep warm, which is uncharacteristic of foxes. The sampson fox usually spends its evenings sleeping underground or even under buildings since it has no thick fur to keep it warm at night when "normal" foxes are out and about. We are so used to the image of a fluffy tailed fox, we get freaked out by a naked one, with a long skinny tail, and big pointed ears etc. and "chupacabra" comes to mind.
That said, I DO believe in breeding and species evolution. I have no doubt certain genes get passed on, especially in smaller gene pools, and recessive genes become more dominant due to inbreeding or just plain small genetic diversity of certain species populations. Therefore I dont discount the possibility of the ""chupacabra"" being a type of coyote, fox or whatever, that has evolved through limited genetic population into a sub-species of a more common animal, especially considering the hard times predator animals face with hunting, farming, trapping, and the development of land. Creation of a new subspecies can take several generations of offspring to be consistent. Maybe thats why so many versions of "chupas" are described. If you think about your chickens, there were probably only a few breeds of them a few hundred years ago, but through breeding, small gene pools, and likely a little inbreeding, there are literally hundreds of breeds of chickens, that are all different in there own rights. And 2 barred rocks make another barred rock. And 2 buff orps make another buff orp. But many generations of breeding buff orp/barred rock cross into each other over and over could possibly produce a whole new species, that always produces the same type of offspring (shall we call them barred orps?) And this is because of dominant and recessive genes, and natural selection. It is the same reason Swedish people are known for their blonde hair and blue eyes, and Italians are known for their olive toned skin and dark hair. Of course they are all HUMANS. But they have different genetic backgrounds. Recessive genes in a localized gene pool have the ability to become the norm - the dominant gene-when they are given opportunity to mingle with other recessive genes. And likewise, dominant genes have the ability to overpower recessives and eliminate them altogether in the same fashion. If it can be so obvious in humans, chickens, cats(ever notice how all the stray cats in a certain neighborhood kinda all look the same?)...why not coyotes? or foxes?
Thats my take on it, for what its worth. Evolution at work.
Thats not meant to offend anyone with different beliefs than I have. We should celebrate diversity in ALL aspects, whether its genetic, or otherwise.