Dogs and yawning

Did you know that there's some evidence to suggest that dogs catch human yawns [1]? That may not sound very interesting, but it could have important implications and might even suggest that dogs experience empathy with humans. Many dogs owners (myself included) insist that our dogs know how we're feeling, and yawning contagion is considered to be related to empathy, at least among humans. For instance, people with autism are less likely to catch other peoples' yawns, and autism is believed to affect the ability to experience empathy.

The links aren't rock solid, though.  First, do we really know why dogs yawn? Is it because they're tired or for some other reason, like confusion? I can imagine if I started making weird yawning faces in front of my dog, she might become confused! On the other hand, it looks as though we're only just getting a good handle on why people even yawn: http://www.blueridgenow.com/article/20100511/ARTICLES/5111013/1018

Beyond that, another study suggests that dogs don't catch human yawns at all [2].  However, the methods were different than in the first study.  While the first study had the humans yawning in the room with the dog, the second study just had video playback of the humans yawning.  That could have affected the results.

Do dogs catch human yawns? Maybe. Does that mean they know how we're feeling? Not necessarily. Has the lack of scientific evidence ever changed the mind of a dog owner on this subject? Not a chance.

References
1. Joly-Mascheroni, R.M., Senju, A., Shepherd, A.J. (2008). Dogs catch human yawns. Biology Letters, 4 (5): 446-448.
2. Harr, A.L., Gilbert, V.A., Phillips, K.A. (2009). Do dogs (Canis familiaris) show contagious yawning? Animal Cognition, 12 (6): 833-837. 

What's the difference between a dog and a wolf?

OK, so wolves and dogs don't really look alike, and the wolf has a bigger brain, and dogs are much better at worming their way onto the sofa. But they are genetically very similar. So what's going on?

Study one: morphological differences between wolves and dogs
You may have heard of this one; it's been getting a lot of press in the past few years.  A group of Russian researchers back from 1959 tried to manipulate Silver Foxes to make them tamer.  At a fox farm, they selected the foxes that were least fearful of the approach of the human hand.  Over the course of several generations, lo and behold, the selected foxes were indeed tamer. But other changes started happening too. For instance, their ears drooped, their tails lifted, their coats changed color, they started barking, and they even started having two 'seasons' per year instead of one. Do these attributes sound familiar?

Study two: social cognitive differences between wolves and dogs
In a two-way object choice task, a dog or wolf subject had to choose a container baited with a treat out of a choice of two, based on pointing cues given by the experimenter. That is, there were two containers on the floor, and one had a treat inside. The experimenter pointed at the container with the treat, and the dog or wolf then made a choice of where to look for the treat.  There was no deception here; the experimenter always pointed toward the baited container. The researchers examined the responses of dogs and extremely well-socialized wolves at the age of eight weeks, four months, and one year.  The results were comparable at eight weeks and one year, but the dogs did better at four months old than the wolves.  Throughout all of this, the dogs learned much more quickly and easily to make eye contact with the human carers and to generally be sweet.  The wolves took much longer, but they did eventually learn to make eye contact and cooperate with the humans, and that could account for their similar performance at one year old.

So, can you turn a wolf into a dog by rearing it like a dog? No. Wolves raised like dogs are still different from dogs.  But, they can still eventually learn to communicate with us, it just takes longer.  It may be that the domestication process has given dogs the inclination to cooperate with us.

The subject of social cognition in the dog has a growing body of literature looking at the interplay between domestication and learning.  I only cite one article on that topic here, but it's worth knowing that there's plenty of good reading on the subject if you're interested. 

References
Belyaev, D., 1979. Destabilizing selection as a factor in domestication.  Journal of Heredity,  70: 301-308.

Gacsi, M., Gyori, B., Viranyi, Z., Kubinyi, E., Range, F., Belenyi, B., Miklosi, A., 2009.  Explaining dog wolf differences in utilizing human pointing gestures: selection for synergistic shifts in the development of some social skills. PlosONE, 4: e6584.

Incentive Contrast in dogs: Or, dogs get really used to having good treats

I just read an article from a research group in Argentina that looked at dogs' reactions to Successive Negative Contrast. This fancy word basically means that if animals (usually mammals) are consistently given a very high-value treat and then suddenly switched to a lower-value treat, they get annoyed about it.

In dogs, it played out this way:  some dogs were consistently given beef liver treats by experimenters, and other dogs were given beef liver treats at first and then switched to the dog's usual meal-time kibble. The dogs that were switched to the kibble were more likely to refuse to eat this lower-value treat, and they also were less likely to engage the experimenter either by making eye contact or approaching him/her. So, the dogs flatly refused to eat food that they ordinarily ate with no complaints, all because they had become accustomed to getting a much better treat.

So, there you have it, if you try to shortchange a dog, it'll get angry. Something to keep in mind when people are training their dogs using food rewards. Make sure that the 'jackpot' treats are used only on special occasions, and also be sure that you don't start out using the Best Food Ever during training, because the result may be a less-than-cooperative dog if you have to switch to a lesser treat.

Reference
Bentosela, M., Jakovcevic, A., Elgier, A., Mustaca, A., and Papini, M., 2009.  Incentive contrast in domestic dogs (Canis familiaris). Journal of Comparative Psychology, 123: 125-130.

What's this blog about?

I am doing PhD research into dog cognition, and this blog will give details about the latest news coming out of this field. There is some interesting and insightful work happening in this area, but many dog owners will not be very surprised with the findings.

Email me at dogresearcher@gmail.com