Doggone it, I now know why dogs hate postmen

I HAVE a dog. He’s a playful, good-natured mutt of dubious ancestry, probably involving a liaison between a pointer and a spaniel. He does have one vice: a deep hatred of postmen. I met our postman the other day and apologised for the dog’s unwelcoming reception every time he made a delivery.

He said not to worry — he was used to it: all the dogs on his round hated him. The mystery of why dogs hate postmen may not be the most pressing scientific question of our generation, but it is intriguing.

The first thing you do when you’re trying to solve a scientific problem is to check the literature. There’s not a lot out there, but I did come up with a couple of suggestions. One was that dogs dislike people in uniforms. This is an unsatisfactory explanation. First, nowadays postmen, at least in rural Ireland, seldom wear uniforms. Then, we are also left with the questions of why dogs dislike uniforms and how they can tell what a uniform is?

Perhaps there are places in this country where the sight, for example, of a garda uniform causes fear in people and this fear is transmitted to their dogs. But it’s not like that where I live. A more ingenious explanation that I uncovered is that the postman is the only person who regularly visits your house, but is never invited inside so your dog assumes that he must be unwelcome.

There’s an increase in the use of American-style mail boxes on the gateposts round here, so the postman doesn’t come to the door as much. I get on very well with our postman and we often have friendly chats. Well, as near to a friendly chat as you can manage while you’re holding on to a snarling, bristling, barking canine that’s making it clear that if you would just let go of that collar he would amputate the guy’s leg below the knee.

However, the fact remains my dog knows the postman and I are friends. The dog was inherited from relatives, so I phoned them up to see if they could throw any light on things. Oh yes, they said, he learnt that from Lucy. Lucy is their elderly sheepdog. This was my first eureka moment. The postman hatred could be learned behaviour and not genetically inherited, and it might be learned from other dogs rather than from humans.

When I thought about it, this was blindingly obvious. Genetically inherited behaviour would have to go back hundreds of generations, probably to a dog’s wolf ancestors. Fifty thousand years ago, there were no postmen roaming the tundra because the postal service was only developed in the 19th century.

I started observing my dog more closely. One strange thing was that he started getting agitated a long time before the postman arrived. He would bristle and growl and look out of the window when the van must have been a kilometre away. And he was hardly ever wrong.

That’s when the penny dropped. My dog was not reacting directly to the postman, he was reacting to the slowly approaching wave of sound created by other dogs. They were telling him that something dangerous was approaching and he was preparing to pass on the alarming message. This is a combination of behaviour learned from other dogs and the genetically inherited instinct to pass on the news of approaching danger to other members of the wolf pack. I must tell my nice postman about this. It’ll make him feel better.

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