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Human beings and dogs, Aug 6th 2011 P67 N5P146 ゛人間と犬゛(書評)?

The relationship between people and dogs is unique. Among domesticated animals, only dogs are capable of performing such a wide variety of roles for humans:herding sheep, sniffing out drugs or explosives and being our beloved companions. It is hard to be precise about when the friendship began, but a reasonable guess is that it has been going strong for more than 20,000 years. In the Chauvet cave in the Ardeche region of France, which contains the earliest known cave paintings, there is a 50-meter trail of footprints made by a boy of about ten alongside those of a large canid that appears to be part-wolf, part-dog. The footprints, which have been dated by soot deposited from the torch the child was carrying, are estimated to be about 26,000 years old.

The first proto-dogs probably remained fairly isolated from each other for several thousand years. As they became progressively more domesticated they moved with people on large-scale migrations, mixing their genes with other similarly domesticated creatures and becoming increasingly dog-like (and less wolf-like) in the process. For John Bradshaw, a biologist who founded the anthrozoology department at the University of Bristol, having some idea about how dogs got to be dogs is the first stage towards gaining a better understanding of what dogs and people mean to each other. Part of his agenda is to explode the many myths about the closeness of dogs to wolves and the mistakes that this has led to, especially in the training of dogs over the past century or so.

One idea has governed dog training for far too long, Mr Bradshaw says. Wolf packs are supposedly despotic hierarchies dominated by alpha wolves. Dogs are believed to behave in the same way in their dealings with humans. Thus training a dog effectively becomes a contest for dominance in which there can be only one winner. To achoeve this the trainer must use a variety of punishment techniques to gain the dogs submission to his mastery. Just letting a dog pass through a door before you or stand on the stairs above you is to risk encouraging it to believe that it is getting the upper hand over you and the rest of the household. Mr Bradshaw argues that the theory behind this approach is based on bad and outdated science.

Dogs share 99.6% of the same DNA as wolves. That makes dogs closer to wolves than we are to chimps (with which we have about 96% of our DNA in common), but it does not mean that their brains work like those of wolves. Indeed, outgoing affability of most dogs towards humans and other dogs is in sharp contrast to the mix of fear and aggression with which wolves react to animals from other packs. ゛Domestication has been a long and complex process,゛ Mr Bradshaw writes. ゛Every dog alive today is a product of this transition. What was once another one of the wild social canids, the grey wolf, has been altered radically, to the point that it has become its own unique animal.゛If anything, dogs resemble juvenile rather than fully adult canids, a sort of arrested development which accounts for the way they remain dependent on their human owners throughout their lives.

But what makes the dog-wolf paradigm especially misleading, Mr Bradshaw argues, is that until recently, the studies of wolves in extremely artificial conditions. In the wild, wolf packs tend to be made up of close family members representing up to three generations. The father and mother of the first lot of cubs are the natural leader the pack, but the behavioural norm is one of co-operation rather than domination and submission. However, the wolves on which biologists founded their conclusions about dominance hierarchies were animals living in unnaturally constituted groups in captivity. Mr Bradshaw says that feral or ゛village゛ dogs, which are much closer to the ancestors of pet dogs than they are to wolves, are highly tolerant of one another and organise themselves entirely differently from either wild or capative wolves.