No one trainer or person "debunked" the theory of dominance hierarchies in dogs. I like to think of it less that it's been "debunked" and more that once, it was the leading theory in the behavioral biology understand on dogs, and we have since grew out of it as dog behaviors has been studied more intensively.
The model itself grew out of very, very early scientific inquiry into dog behavior in the 40-60's, when the popular scientific understanding was that dogs could be best understood by looking into wolf behavior. Prior to that, there was little to no inquiry into the biological behavior of dogs- how they thought, how they learned, how they behaved with humans and with each other. It was considered a waste of time to think about those things in the scientific community. One of the very first scientific studies done looking into canine behavior was in the 40's on Wolf Park captive wolf packs- this is the study from which this idea of dog/canine behavior stems from. Since the study in the 1940's, other studies have introduced new information and leading scientific minds (including the scientist who did the original study in the 40's, and many well known dog trainers) have come to the general consensus that:
- dogs are not best understood through wolf behavior because dogs are not wolves (remember: the dominant/submissive/pack leader whatever model of dog behavior is based largely on studies done
on wolves)
- Why? Because many thousand years of divergent evolution separate dogs from wolves (it seems plausible that early proto-dog populations and wolves diverged sometime before the advent of agriculture, at least 14 thousand years ago, and possibly began to diverge as early as 20,000 years ago. The earliest fossil records of animals that can confidently be described as "dogs" based off of skull/skeletal markers are around 14,000 years old. Genetic evidence places the divergence more like 20-100,000 years ago. Geneticists will usually argue that date, while archeologists will usually argue the date suggested by the fossil record. The scientific community at large has mostly agreed on 14-20,000 years ago as the approximate date of divergence.)
- furthermore, the grey wolves of today are not the grey wolves dogs "evolved from" (which is a simplistic explanation of evolution but adequate for this explanation)- the conditions that determine the best fit animals/behavior (and thus the best fit genes) have changed drastically in that time (including a global take over by our species) and make it likely that the grey wolves of today are not representative of the behavior of grey wolves prior to the beginning of the divergence between wolves and dogs, or the wolves whose genes dogs "share". Some genes remain static between dogs and wolves today, but those are genes inherited by a common ancestor prior to their divergence-
not genes dogs have inherited directly from the grey wolves of today
- the way to understand dogs is to do studies on dogs, not to do studies on wolves
When the model of dominance theory was first proposed, it was ground breaking stuff, and it fit very well into the training methods used in the day, which included a whole lot of punishment and physical manipulation and not a whole lot of reward other than praise/petting. If you look at early stuff being put out by people who are now ground breaking in the positive reinforcement world, such as Ian Dunbar, you'll see them using what people who idolize them today would think of as pretty knarly punishment based techniques. The entire understanding of the best ways to train dogs has changed drastically since the advent of dominance theory. Dominance theory training has not done a whole lot to absorb these changes, which have all occurred because of increased scientific inquiry and understanding of dogs behavior.
My bone to pick with dominance theory- and the issue most of its critics have with it- is not that what they call "dominant" and "submissive" temperaments do not exist in dogs or should not factor into the kind of owner/training a dog or breed or type is best suited to or do not on some level determine how a dog interacts with its world. Anyone who has spent any time around dogs knows that this kind of thing exists. I've seen the scientific community refer to it as a "shy/confident" temperament spectrum sometimes, which I prefer. I really like the term "domineering" or "assertive" to describe a confident animal (what dominance theory trainers call "dominant") and "soft" to descrive what they'd call "submissive". It is more the way that dominance theory trainers view that temperament spectrum that I take issue with- because dominance theory trainers are viewing that temperament spectrum through a lens colored by assumptions about dog behavior that are based on extrapolations of (somewhat flawed) studies done on wolf behavior, they are assuming that temperament spectrum is the absolute most important factor in dog behavior and the most important thing to determine their training and how easy they will be to train. I have already explained why I- and many scientific minds/ trainers- find wolf behavior to be a faulty lens through which to understand dogs, and also explained why those extrapolations of wolf behavior are faulty (namely: that is now how wolves actually behave in the wild).
When I say things like "dominance theory has been debunked" on this forum, I don't mean that an animal's personality and where it sits on the shy/outgoing (or "submissive"/"dominant/assertive") spectrum of behavior doesn't factor into the kind of ownership, management, or "leadership" (which are all fairly intertwined words, IMO) that it needs to thrive/live safely in human society. I also balk at using the words dominance theory trainers use because "dominant"/"submissive" have very specific scientific meanings, and they relate to individual situations and resources, not universal relationships. Obviously they have come to have a colloquial meaning that is different from that, but that doesn't change the fact they already meant something specific and different, so I avoid using them in those situations.
Overall, in both wolves and dogs, there is not a whole lot of evidence that suggests that animals have to fight for social status or that the struggle for social status is the single most important factor in determining dog-dog and dog-human relationships. There is also strong support for the social status of an animal to be mostly reinforced by the lower ranking animal offering spontaneous appeasement displays.
(cont. in next post)
http://www.clickersolutions.com/articles/2001/dominance.htm