Domesticated dogs have been described as a “genetic cocktail” due to the variety and diversity of breeds. Every breed was developed by humans to serve specific helper roles such as hunting or herding. Dogs are bred for physical traits as well as for consistent temperaments. Some breeds are naturally more independent or aloof while others are friendlier. You’ll want to choose a breed known for being affectionate with people if you’re looking for a companion or service dog.
Dogs desired for companionship and partnership with humans were bred to reduce the natural instincts of predation, dominance and aggression which are heritable traits. According to Michael D. Breed in his article What is the Basis for Aggression in Dogs?:
Certain breeds have been selected for enhanced dominance and aggression. Pit bulls and Rottweilers currently receive the most public attention in this regard, and pit bulls have been banned in many locations because they are perceived as being dangerous. While advocates of these breeds claim that maltreatment is a more likely underlying cause of the kind of aggression leading to biting incidents (some of which involve human fatalities), in fact we know that personality is fairly unresponsive to environment.
Working from Stanley Coren’s dog intelligence study, Hellmuth Wachtel categorized dog breeds into these groups of heritable trainability:
Any companion or service dog must have a high level of bite inhibition. Puppies should be tested for aggression and dominance, as well for other personality traits, because you cannot change your dog’s genetic blueprint. What you get from your dog’s breeder is what you will have to work with. That’s why it’s so important to research and locate a breeder able to show success in breeding dogs suitable for service work or companionship.
Geneticists emphasize what we see as one heritable behavior actually results from a complex interaction of multiple genes. For this reason it is important that working dogs must be bred for their purpose at every generation otherwise the combination of genes required to produce the desired behavior may become separated, and subsequently lost.
Never underestimate puppy aggression; it is a good indicator of what to expect from the dog as an adult. Since pit bulls and Rottweilers are the most likely to kill people, they are not suitable choices.
Body language signs of an aggressive puppy:
CASE STUDY: The Russian Fox Study
A fifty year study by a Russian scientist hypothesized that breeding “for tameness and against aggression would result in hormonal and neurochemical changes, since behavior was ultimately rooted in biology. It could be that the genetic differences that led to the morphological changes that biologists noticed in domesticated dogs (particularly, they noticed differences in fur coloration, and increased skull size relative to body size) were related to the genetic changes that underlied the behavioral temperament that they selected for (tameness and low aggression). He believed that he could investigate some of the questions about domestication by attempting to domesticate wild foxes. Belyaev and his colleagues took wild silver foxes (a variant of the red fox) and bred them, with a strong selection for inherent tameness.”
“And so it was that selecting for a single behavioral characteristic – tameness (or, put another way, selecting against fear and aggression) – resulted in changes not only in behavior, but also in correlated and unselected physical and physiological changes.”
“In the middle of the 19th century, there was a family of pit dogs in Ireland that were known as the ‘Old Family’. At that time, all the strains were closely inbred. Being a small genetic pool of that type, it was likely to have a slide toward the recessive traits, because the dominants, once discarded, were never recaptured. Since red is recessive to all colors but white, the ‘Old Family’ eventually became the ‘Old Family Reds’. When the dogs began coming to America, they were beginning to show the red nose.
Many strains have been crossed with the Old Family Reds at some time in their existence. Consequently, nearly any strain will occasionally throw a red-nosed pup.
To many dog owners, these red-nosed individuals are Old Family Red Noses even though the great preponderance of their blood is that of other strains. Sometimes such individuals will fail to measure up and thereby reflect undeserved discredit on the red-nosed strain. Originally renowned for its gameness, some of the most reputable breeders in all Pit Bull history such as Lightner, McClintock, Menefee and Wallace have contributed to the preservation and development of the strain.”
Below are some videos showing very young puppies displaying their inherited behavior.
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