Thinking....Doggiestyle

Thinking Doggie-Style
Has our long shared history with dogs shaped their brains - and ours?
By David Hambling
December 2010

Photo by Etienne Gilfillan

FT271

A common – if unlikely – claim made by dog owners is: “He understands every word you say.” But scientists are increasingly finding that it might be truer than you think. The evidence suggests that the two species have moulded each other over a long period of co-evolution, and have developed sophisticated communications in the process.

Archæological findings show that dogs were first domesticated at least 10,000 years ago, with one find at the Goyet Cave in Belgium recorded in 2008 possibly pushing that back to 30,000 years. Genetic studies indicate that the process of domestication that split dogs from wolves may date as far back as 100,000 years. And the relationship may have started long before that, as some archæological finds put humans and wolves in the same place 400,000 years ago.

The aptly named biologist Wolfgang Schleidt suggests that the two came together in Northern Europe at a time when humans – either Homo sapiens or the earlier H.erectus or H.heidelbergensis – existed in small nomadic groups. Humans joined wolves in their following of migratory reindeer, and the two races of hunter-scavengers started working together.

The success of the wolf pack hinges on the members’ ability to work together without conflict and share the kill. Recent work with dogs shows that they have a sense of ‘fair play’, previously thought to be limited to primates. The experiment at the University of Vienna involved training dogs to extend a paw. The dogs were happy to perform this trick with or without a reward when on their own. But if they were with another dog which received a reward when they did not, the dogs quickly refused to play.

We don’t know yet whether wolves share this attitude. Some have suggested that dogs became attuned to fairness as an adaptation for living with humans. This seems questionable: the phrase “a dog’s life” dates back to the 17th century, meaning “a life of misery, or of miserable subservience”.

Perhaps humans gained their own notions of fairness from their companions during the period when the two worked together. Wolfgang Schleidt sugg­ests that “wolves and dogs, with their remarkable capacity for co-operation and loyalty, were both role models and companions on this long trek toward humanity.”[1]

Sherlock Holmes once noted the curious silence of a dog, which failed to bark in the night (clear evidence to the great detective that an intruder was known to the dog). However, what is really curious is that dogs bark at all. Barking is rare among wolves, whose vocal commun­ications are generally howls or growls. Barking appears to have been evolved to talk to people.

Barking is more effective at getting human attention than growling. Peter Pongracz, a behavioural biologist at Eotvos University in Budapest, has shown that the pattern of barking is different for aggression, loneliness and happiness. Pongracz’s team recorded hundreds of different barks from different situations. Not only were the barks consistently differ­ent depending on the dog’s emotional state, but even people who had never owned a dog were able to correctly interpret them. Our long association with them means that understanding dogs is hardwired into the human psyche.

Humans and dogs also share the ability to follow a gaze or gesture to see what someone else is looking at or indicating. This is very unusual in nature – even chimpanzees have trouble with pointing tasks. However, the same team at Eotvos University also showed that dogs are capable of following both gaze and pointing. This should not come as any great surprise when you consider what Pointers are bred to do. Wolves are also capable of learning the same tricks, but it is much harder for them: unlike dogs they are not used to looking at humans.

Again, it would be interesting to know if pointing or gaze-following is a natural skill in wolves that humans – being mere primates and a bit slow – gradually acquired over time.

Dogs also read human facial expressions. A team at the University of Lincoln has found that dogs show what is termed ‘left gaze bias’. This is the tend­ency, when looking at a human face, to look left (i.e. at the right-hand side of the face) first, and to spend more time looking at this side. Left gaze bias has already been established as a human trait and only occurs when looking at faces. The reason for it is that emotions register more clearly and more intensely on the right side of the face. And dogs have been around humans long enough to have face-reading in their genes.

However, while it might seem that dogs and humans have evolved to understand each other very well, there is one huge gap. Children under the age of five have very little understanding of dog body language or barks and can’t tell a happy dog from an angry one. An excited child may try to hug this big fluffy toy, with disastrous results. Dogs and small children should always be supervised; possibly ancient humans didn’t leave children alone with dogs the way their modern descendents are prone to. Or perhaps evolution still has some work to do.

So far, research into dog-human communication has only scratched the surface; but the indications are that, even if they don’t catch every word, dogs understand us very well indeed because they shaped our brains as we shaped theirs.



NOTES
1 WM Schleidt: “Apes