"The dog who growls at a human could some day bite and, if bred, is likely to produce offspring with the same problem--or worse...|
"...breeding for higher levels of showmanship and other types of competition produces greater aggressiveness, which in turn leads to greater likelihood of growling and biting...
"Unconscious selective breeding in dogs is the production of traits that were not especially bred for but which evolved by accident, such as the difficulty in housetraining some toy breeds" (Metzger, Susan. "Flat-Coated Retrievers," Breed Column. AKC Gazette, Oct. 2003, 53-54).
Colby Glass, MLIS