Anyone who has or has had dog Have you ever seen how your furry friend greets you with a wagging tail when you arrive home. Or when she approaches him with a bowl of food. This and many other reactions have always led us to think that dogs wag their tails when they are happy. However, the truth is that there is no scientific consensus on the matter.
In fact, a team of Dutch and Austrian scientists just published in Biology Letters an alternative hypothesis, based on the analysis of more than 100 studies on the subject. It should be noted that theirs is not a typical study, but rather an opinion article in which they also follow a scientific method to state a hypothesis about the reason why dogs wag their tails.
According to them, although it is true that they move it when they are happy, the reality is somewhat broader. Possibly, it is a movement resulting from the process of domestication, which responds to almost any emotional impulse, not necessarily happiness. This is supported, above all, by a study carried out with foxes. But let’s see how they arrived at this hypothesis.
Background on why dogs wag their tails
In this new article, its authors cite several studies about the causes why dogs wag their tails. Several stand out. For example, one in which it is shown that aggressive dogs They are the ones who tend to wag their tails the most. Also another one in which they generally do this movement when they want food, so it could be a way to make a petition, more than showing happiness. In fact, this behavior has been detected with other many emotions.
But, without a doubt, the studies that have taken the most into account are the experiments carried out with silver foxes. This is actually not a different species of fox. This is a case of melanism, like that of black panthers. They are foxes that are born with an imbalance of normal pigment levels, so instead of looking brown, they develop a grayish black color.
They are very well known in science, since in recent decades Several domestication experiments have been carried out with them. That is, they have been bred and selected, generation after generation, to demonstrate how this behavior can change a species. Exactly like wolves They turned into dogs.
In one of these experiments, developed during 40 generations, It was observed that most foxes had the characteristic movement of the tail that dogs also have. When the desired features were selected, there was never a thought about that. The main idea was for the foxes to become docile and friendly. However, they ended up wagging their tail, why?
A question of rhythm
The hypothesis of the authors of this last article is that dogs wag their tails for a unconscious domestication. That is, when generation after generation were selected, from wolves to dogs, humans selected those that moved their tails, but they did not realize it. This is because human brains have a natural preference for rhythmic stimuli. That’s what makes us such musical animals.
Although we are not the only ones. There are studies which show that other mammals, such as mice, also prefer these stimuli. It is possibly due to an ancestral form of timing. So your dog may not wag his tail out of happiness when you get home. Or maybe yes. But, in reality, if he does it, it is because a very distant ancestor, without realizing it, decided that it was better to perpetuate those little wolves that moved their tails for almost any emotion.