I am always amused by the number of my friends on Facebook who post about dogs. Sometimes, on a given day, half the posts are canine related. I don’t often read them as I dislike dogs (I must be one of a tiny minority in the population, and you will have to wait till the end of this post for the reason for this). But it makes me wonder what this obsession with dogs is all about. What is the nature of the bond between my friends (otherwise rational and sensible individuals), and their canine companions that they want to share their doings so often? It must be pretty important to the readers as well, as these posts always attract many comments.

We certainly know that keeping pets, and particularly dogs, is good for your health. A study done in 1991 looking at whether people’s self reported health improved over 10 months after acquiring a dog, as measured by the General Health Questionnaire, found that it did. Headaches, hay fever, nerves, palpitations, indigestion and constipation, all reduced markedly in this group. The study also looked at people who had acquired a cat, and found that though their self reported health also improved, it was not as great and did not last nearly as long. The researchers marked up the beneficial effects of having to walk the dogs as a major contributor to the positive health effects for dog owners over cat owners. But the main benefit was thought to be the improvement in psychological health of having a companion to share their social life and experiences.

Some people say that their dogs are incredibly intelligent, and that they really understand their owners’ commands and needs. But we don’t now think that is the reason why humans and dogs get on so well. Many birds, especially parrots, and of course chimpanzees, have much better problem solving abilities than dogs. But domestic dogs are unusually skilled at reading human social and communicative behavior – even more so than chimpanzees. If you hide a piece of food or an attractive object in one of several opaque containers, and then look at or point to that location in an attempt to help the subject find the hidden object, a dog will usually do this task very easily, and it is instinctive – they do it from early puppyhood. Human infants find this task trivially easy from around 14 months of age, but chimpanzees find this very hard; they seem to have difficulty with understanding the human’s gaze. Dogs, like human infants but unlike chimpanzees, only use the human head and eye direction cue to locate hidden food if the person is gazing directly at one of two possible hiding locations; they ignore a human’s gaze if the person stares into space above the correct hiding location. So dogs really do know how humans communicate and use similar methods..

Apparently dogs evolved from wolves many times over the centuries, and the first thing that had to happen was that the wolf/dog had to learn to overcome its natural fear and aggression on encountering humans. This must have been selected for because those individuals who did so were able to get food remnants from around human habitation. Once this had happened there would be biochemical changes in systems mediating fear and aggression, such as hormonal and limbic changes, so that dogs can develop emotional reactivity and human-like social skills. Thus human and dogs subsequently co-evolved to enable them to understand each other in ways that other more intelligent animals such as chimpanzees could not. It has been suggested2 that a similar situation had to evolve in hominids before they could co-operate with each sufficiently to develop human social skills and communication including speech.

Cats of course don’t do any of this, and I don’t see many cat posts on Facebook (though there are some). I quite like cats, as they are very undemanding. But I have been put off dogs for life, after years and years of visiting patient’s homes and having to negotiate dogs which insisted on protecting their human (my patient) from me! They are usually harmless of course, although it is difficult to examine a patient properly with a dog barking and jumping up trying to stop you doing it. But sometimes they are not so harmless. One of our nurses had to visit an eighty-year-old lady who was very immobile and had many medical problems, twice a week. Unfortunately the lady lived with her husband and a Rottweiler. The husband was supposed to exercise him, but was equally elderly and probably didn’t. The dog was bundled into a back room whenever the nurse came and for some time there were no problems. Then one day the lady forgot to shut the back room door and the dog got out, immediately sinking his teeth into the nurse’s leg. There was quite a bad bite that needed treatment in hospital and the nurse was off work for three weeks. Then of course the question was – is the nurse required to visit? The couple refused to get rid of the dog, and the replacement nurse refused to go. Her employers, the Health Authority first insisted that the new nurse had to go if the patient needed a visit, but she still refused, and there was a long bad tempered argument about this. In the meantime the lady still needed treatment (she had leg ulcers) and eventually she went in by taxi to have it done in the surgery. We couldn’t understand why she wouldn’t get rid of the dog – having a Rottweiler cooped up in a small house with no exercise seemed like cruelty to the dog. So we called the RSPCA but they said the dog was healthy and took the side of the elderly couple. But the nurse still refused and the first nurse then I think threatened to sue the Health Authority under Health and Safety legislation, and so there was stalemate. It ended some months later when the couple decided to get rid of the dog and visits resumed. I am personally of the opinion that any person visiting a home for professional purposes should be entitled to be safe and I think this has now been accepted – in the case of postmen at least!

I have known patients go into a deep depression on the death of their pet, and we used to try to remember the name of the pet in order to talk about it in the surgery, just as we would with a family bereavement. And people will spend the earth on veterinary treatment for their pets that they certainly wouldn’t spend on themselves. Yes, I think the dog/human relationship is a very fundamental one, and isn’t going to stop anytime soon. But I still don’t think I am going to read these numerous posts on Facebook about them!

References
1. Serpell, J. A. (1991). Beneficial aspects of pet ownership on some aspects of human health and behaviour. Journal of the Royal Society of Medicine, 84, 717–720.
2. Brian Hare and Michael Tomasello Review Human-like social skills in dogs? TRENDS in Cognitive Sciences Vol.9 No.9 September 2005