== who came up with this theory? at the genetic level??? == 

 "Domestication (from Latin domesticus: "of the home") is the process whereby a population of living organisms is changed at the genetic level, through generations of selective breeding, to accentuate traits that ultimately benefit the interests of humans." Yes, certainly over many generations there will be changes at genetic level, but this certainly is not a criterion for "domestication". A broader definition is required for the intro before going into more technical definitions. I can rescue orphans lion cubs or elephant calves, take them home and raise them. These will grow up as domesticated and might even no longer be able to adapt back into their natural conditions. No genetic change has occurred and even if these cubs and calves grow up to have young, still nothing will have changed over and above any changes that would have happened regardless of not living in the wild or not.