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Name: Roberto
Status: Other
Grade:  Other
Location: TX
Country: United States
Date: May 2006


Question:
I was watching a show on wolf/dog evolution and a point was made that the dog genetics contain much variability - implying that dogs carry many unexpressed genes which can be expressed by controlled breeding.

So I got to wondering - does a chihuahua, say, actually carry -unexpressed- the gene for a great dane or its parent wolf? More importantly, if this is true, could we turn a chihuahua back to a wolf with selective breeding? And most interestingly, could we -over the course of many generations- ultimately breed for dog/wolf ancestors that are already extinct?



Replies:
No doubt they have unexpressed genes...also, in outbreeding you would see at least some of the "ancestral" body shape reapear. Recall that there is very little genetic difference between all dogs since they can interbreed...including with the wolf...in my opinion, by definition the common domestic dog should be classified as the same species as the wolf...because they can readily interbreed. As far as resurecting extinct ancestors from extant species....it seems unlikely...but when it come to genetics, I am never surprised at what seemed once impossible is now fact.

PF


All breeds of dogs were derived from wolves as a result of mutation of wolf genes and selective breeding by man. These mutations were not carried by the ancestral wolf but arose during the 15,000 years they have been under domestication by man. Theoretically, it would be possible to evolve a wolf-like dog from Chiuauas, but it would take thousands of generations waiting for the right mutations to occur. The resulting "wolf" would look like a wolf but would not be genetically identical to wolves.

Ron Baker, Ph.D.


You couldn't turn an individual dog into another kind. Individuals don't evolve. But if you kept selectively breeding one dog to another, after many generations its descendants would begin to look different over time. You would also have to breed many individuals and have many many offspring because you couldn't always be sure of what traits the offspring are going to express. There is no guarantee that you could back cross to the original wolf type.

vanhoeck


A very interesting question. While I am not a geneticist, my understanding is that yes, with enough generationg - and it might be a great many -some breeds of dog could be derived from others. I don't know if a specific breed could be recreated. The question of breeding back to extinct ancestors has been brought up in theory and I believe has been attempted with some species.

This site has an article about breeding the extinct quagga from zebras.

http://www.nac.ac.za/stac/quagga.htm

J. Elliott



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