The quantitative aspect is more important than the qualitative one. Take dog races (breeds) for example: "We also showed that the genetic variation between dog

The quantitative aspect is more important than the qualitative one. Take dog races (breeds) for example: "We also showed that the genetic variation between dog breeds is much greater than the variation within breeds. Between-breed variation is estimated at 27.5 percent. By comparison, genetic variation between human populations is only 5.4 percent. Thus the concept of a dog breed is very real and can be defined not only by the dog's appearance but genetically as well." - http://www.americanscientist.org/issues/feature/2007/5/genetics-and-the-shape-of-dogs/2 http://www.americanscientist.org/issues/feature/2007/5/genet...