Dogs: an uncomplicated relationship
Dogs read our body languageHuman babies understand that pointing and gaze direction are indications of what's going in another person's mind. To examine whether this skill is learned or inborn, research has explored these capabilities in our closest evolutionary relatives – chimpanzees and bonobos.
The classic test is to hide a treat in one of two locations then point to where it is. Children from just over a year old will have no difficulty recognising this signal and will come and claim it. Chimps do no better than randomly choosing between the two locations, completely ignoring the cue.
Given that chimps seem to struggle with this task, it was widely assumed that it couldn't possibly have evolved in other, "lower" animals. Do this experiment with your cat and she will probably gaze uncomprehendingly at your finger for a while.
Imagine researchers' great surprise then when it was revealed that dogs, who are miles away from us on the evolutionary tree, passed this task with flying colours. Hide a treat in one of two locations and point at it and dogs will reliably bound over and gobble it up, even when the treats don't smell of anything.
Not only that! If you stand a long distance away and point, dogs will unfailingly go to the right location. If you simply bow or nod in that direction, they get it. If you look at one hiding place rather than another, they get it. Perhaps most impressively, if you walk in one direction and point in the other, they still get it.
Dogs know what grabs our attentionAnother test of mind-reading ability is knowing what someone is paying attention to. Given the option of begging food from two people – one who has seen where the food is hidden and one who has a bucket on his head – chimps will randomly go to either one. Dogs, on the other hand, will consistently choose the person who can see.
If you have a dog you can try this yourself. Throw a ball and then turn away and the dog will almost invariably come round and drop the ball in front of you, where you can see it. This indicates that dogs are not just playing with their humans, they are also keeping track of what their humans are looking at and how best to get their attention. This sort of gaze-reading ability can take months to develop in young children and may never develop in non-human primates.
Dogs love usLike cats, dogs also seem to form strong emotional attachments to their owners in much the same way as human babies do to their mothers. The typical test of babies' attachment is to plonk them down in an unfamiliar environment and see how they fare. If babies have a strong emotional attachment to their mothers they will explore the new environment, returning to her regularly for reassurance, get terribly upset if she leaves the room but be quickly consoled when she returns.
Dogs show an almost identical pattern of responses with respect to their owners – sniffing about, returning to the owner, pawing the door and whining when the owner leaves followed by exuberant greetings on their return. Like babies they are distrustful of strangers in the room with them and tend to show signs of increasing distress the longer their owner is away.
Dogs listen to usFinally there is some evidence that a couple of precocious pooches may have that most quintessential of human skills – comprehending language. Rico, a border collie, has been shown to differentiate at least 200 different labels for objects, an astonishing vocabulary for a canine.
Chaser, another collie, understands more than 1,000 different words! Both will bring you the toy you ask for from a huge selection and will do so even if you instruct them out-of-sight. This means they are not simply picking up on unconscious non-verbal signals.
If you present these dogs with a familiar toy and a new object, then ask them to fetch the "dax" – a word they won't have heard before – they will reliably bring you the new toy rather than one they already know the name for.
This sort of inference is called "fast-mapping" and is thought to be the skill that underlies human children's astonishing speed of language acquisition in early childhood. But even human children don't show this ability to the same degree as Rico and Chaser until about 2-3 years of age.
That dogs are so surprisingly proficient at reading human communication might come as no surprise to dog owners but has been something of a revelation for psychologists interested in how these skills have evolved. What is especially surprising is that they seem much less developed in our closest genetic relatives – non-human primates for humans and wolves for dogs. So these skills cannot be explained by any simple evolutionary model or by straightforward pack behaviour.
What we are finding is that the rudiments of what we thought of as particularly human social skills may have their roots much further back in evolution than previously expected. Alternatively, they may have evolved in different species independently. What seems increasingly clear is that dogs have maintained the reputation of being "man's best friend" not simply through our own benevolence but also through developing an impressive set of social skills that make them ever-sensitive to our whims and fancies.