Has Canine Domestication Been Good for Dogs or Will History Judge it a Disaster?

Posted on April 24, 2018

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The likely origin of all our domestic dog breeds is widely acknowledged to be when people tamed wolves thousands of years ago, but has it been a behavioural and genetic disaster scenario for man’s best friend?

Canine evolution and the domestication of wild dogs are both fascinating and controversial subjects in equal measure. Archaeological and historical records show that humans have heavily influenced the dog’s genetic and behavioural make-up over tens of thousands of years. But how we turned wild animals into close companions remains a mystery.

Science has attempted to make sense of the domestic dog’s origins and to map its trajectory in human society. We may have developed sophisticated relationships with dogs, working with them as hunters, companions, spirit guides, and even using them as food: but we still cannot identify a single point of origin story. Only one indisputable fact remains: canine development is inextricably linked to ours. So has the exchange between man and animal been a positive one?

That depends who you ask. John Bradshaw is a Bristol University behaviourist who has cultivated ideas on canine relations over almost 40 years of study. As an anthrozoologist and author of the book ‘In Defence of Dogs’, he spent the first part of his career researching the dog’s keen sense of smell as a tool for communication and navigation. His attentions eventually turned to highly trained dogs used in the military and drug detection, as well as medical detection dogs that identify disease by its scent.

Dog Noses: a History

“We have made use of the dog’s vastly superior olfactory abilities right through the history of dog keeping,” he says. “People have been imaginative about what they use dogs’ noses for.”
Today dogs are trained to look for contraband including smuggled items like shark fins or ivory. They are also useful in conservation to look for the dung of rare animals and help map out populations. “You could say the dog is experiencing a renaissance in that sense,” says Bradshaw.

Traditional roles in herding animals or as guards are declining in the developed world, but the underlying motivation that glues man and dog together stretches back to the animal’s early domestication. Essentially dogs want to work for humans, says Bradshaw.

“Without that none of these other things – sheep herding or sniffing out bombs – would work,” he says. “That is why dogs are so much easier to train than any other animal. Other animals may have a keen sense of smell, but we use the dog.”

He firmly believes the dog’s perception of humankind has evolved from the pack bonds that young wolf cubs form with their parents and other members of the pack. “Domestication has enabled us to broaden that, so unless dogs have had nasty things happen to them in life, they believe the whole human race is there to be friendly,” he explains. “From the dog’s point of view it is rather straightforward, but that makes it easy to exploit.”

Dog detection

Detection dogs: the dog’s vastly superior sense of smell is one of many attributes humans have exploited.

Kidnapping Wolf Cubs

Understanding this dynamic in the human-canine bond has been a life’s work for another academic. British expatriate James Serpell is an experienced zoologist who runs the Pennsylvania Veterinary School’s Center for the Interaction of Animals and Society. He teaches ethics, animal welfare and shelter animal medicine and has authored books on the domestic dog and human-animal relationships.

Domestication in effect began with an act of kidnapping, says Serpell. People actively captured young wolves and socialised them. “They had to be taking wolf cubs from the den and hand rearing them.” This is in opposition to the idea of gradual domestication based on wolves scavenging from human settlements, he says. “I just don’t see that happening mainly because humans typically are not kind to scavengers, they tolerate them but they don’t encourage them.”

Countless pieces of historical evidence point to hunter-gatherer societies capturing wild animals and rearing them as pets. Large animals such as tapirs, moose and even bears were kept around settlements. If an animal became destructive or dangerous it was driven away, but rarely killed.

“The ones that showed friendly behaviour into adulthood would not have been driven away and would have formed the nucleus of a domestic population,” says Serpell. “A female wolf that mated with either a wild male or a tame male would have had her pups in the village, exposed to people from the start and handled by adults and children. That was a necessary ingredient.”

Bonding in this way has proved as important to dogs as it has to humans. Olfactory recognition played a large part in that process for canines, in the same way that human memories and emotions are strongly associated with certain smells. But there are elements of the dog’s psychological make up that were directly influenced evolution and domestication, which have been neglected.

The Emotional Dog

Gaps in our understanding of visual processing and its link with emotional awareness needed to be redressed. In 2010 a researcher at the University of Lincoln tested the way dogs acquire visual information with a carefully designed psychological experiment.

Anais Racca, a specialist in cognition and the brain, used the same non-verbal methods applied to young children to test dogs’ ability to recognise faces. “They live with humans and are exposed to us, so it would make sense to them to be able to recognise human faces,” she says.

Facial recognition

Dogs can recognise positive and negative emotion in human faces.

Studies were designed to assess how dogs would react to facial expressions, using the concept of brain lateralisation, where the right hemisphere is thought to process negative emotion and the left positive emotion. By recording which side of a picture dogs looked at Racca could assess which hemisphere was processing the information.

“We know already that dogs are interested in human faces,” she says. “They look back at us all the time and not just generally at the body, they look at our face.” Her research shows that they pick up information from faces for identity, but they may also be picking up information about our emotions. “We found that if you present a picture of a face that is either angry or neutral then dogs preferentially look at the left side of the picture.”

This ‘left-gaze’ bias shows the dogs needed to determine the emotional state of the faces using the right hemisphere of the brain. Just as in humans, negative or neutral expressions are registered as potential threats. “This is important for survival,” she continues. “If you want to adapt to new environments then you have to adapt to others’ emotions. If you want to avoid harm and adapt your behaviour to read intentions, linked to empathy, then reading others’ emotions is the basis for a lot of things in social life.”

Interestingly, says Racca, dogs living in a human environment have to cope with the same challenges as children do. By making comparisons we can see the way humans evolved and how we develop through our environment.

Another crucial aspect is that it allows researchers to make a comparison with dogs’ direct ancestors, wolves. “It offers a valuable understanding of the evolution of cognition and how domestication has changed the dog’s behaviour and cognition.”

Soviet Foxes

Evolution in that sense has been more than just a benign relationship between man and dog’s joint ambitions and emotional needs. There has been a certain amount of forcing square pegs into round holes. Take a look at Soviet Russia for evidence. In a strange mirror of the social engineering of the Soviet regimes, a similar process took place in fur fox populations in Siberia.

In the 1950s fur farming took place on an industrial scale, but handling wild animals was a fraught affair. Geneticist Dmitry Belyaev was appointed head of a breeding programme in the Siberian city of Novosibirsk with instructions to breed aggressive traits out of the foxes and make the fur farmer’s task easier.

Successive breeding with relatively tame foxes produced tamer animals. But a number of other undesirable traits also emerged. Tame foxes developed pie-bald, black and white coats – colours that nobody wanted in the farming trade – as well as curly tails, floppy ears (like some breeds of dogs) and softer coats that were less like the bristly wild-type coat. These changes were the result of selecting for tameness.

Belyaev reasoned that the emergence of these traits was unavoidable. Selecting for behavioural responses meant selecting for certain brain neurotransmitter and hormonal activity in each animal. Genes controlling the balance of behaviour occupy a high level position in the genome, he said. Slight alterations in these regulatory genes resulted in the wide developmental changes that he and his team observed, changes that mirrored those of other domestic animals. In this case, docile and floppy-eared with softer coats – just like domestic dogs.

“People have argued that if you look at the wolf population there is a certain amount of variation in colouration: but basically a wolf is a wolf,” says Serpell. “There is not a lot to select for. If you imagine ancient people trying to select for wolves that exhibited certain types of behaviour or wolves that had curly tails, it was not there to begin with.

“The argument posed is that the early process of selecting for tame animals introduced variation that humans could then select from, animals where they liked the behaviour or the appearance.”
Both Serpell and Bradshaw believe that the process of taking wolf cubs from the wild and hand-raising them as pets was the first act in this causal chain. Yet the time frame for this chain of events is a little harder to determine. Evolutionary geneticist Carles Vila suggested in a 1997 paper for Science that domestication could have taken place 100,000 years ago.

Dog burial

Iron Age dog burial

After studies on other species, John Bradshaw believes this was an over-estimate due to misunderstandings about how to calculate mitochondrial DNA evidence. “Archaeological evidence to suggest 100,000 years is very flimsy, but there is still a discrepancy with molecular evidence pointing to perhaps as long ago as 30,000 years,” he says.

Geographic location for the first domesticated wolf is another contested fact. Some point to the Americas, while others say it is eastern Europe or the near east between Turkey and Iraq. Peter Savolainen, molecular biologist (and an author on Vila’s 1997 paper) conducted his own research into mitochondrial DNA and places domestication origins in east-Asia around 15,000 years ago. Speaking to American broadcasters PBS, Savolainen speculated: “One thing is that southern Asian wolves are generally smaller than north-Asian and European and North American wolves, so perhaps they were easier to handle.”

Domestication is a Disaster

For biologist Ray Coppinger this seminal event is hardly the point. For him domestication has been a disaster. It resulted in an unequal relationship between men and dogs that was tainted from the start.

Professor emeritus of biology at Hampshire College in Massachusetts, he says there are seven or eight categories of co-evolution or symbiosis. “One symbiotic relationship that is studied more than the others is parasitism, which is bad for one species and good for the other. Often parasites are obligatory parasites meaning they [are associated with] a particular species and even a particular part of a species. So sheep and stomach worms have a symbiotic relationship.

“An ethologist studying dogs would say that the dog has a commensal relationship – eats at the same table – with humans. For dogs it is obligatory. That means if dogs disappeared from the world today it would make no difference whatsoever to the reproductive health of humans. But if humans disappeared dogs would immediately become extinct.”

The adoption of dogs as pets escalated after the end of World War Two with the burgeoning middle class. Their popularity as pets stimulated growth in popular myths about how, when, where and why evolution happened and what it means to us. A more interesting question, he says, is why dogs are so reproductively successful and why wolves, dingos, jackals and other wild dogs are headed for extinction.

“There are about half a billion dogs in the world and about 45 million of all the rest,” says Coppinger. “That means 500 million dogs living and breeding like any wild population and obeying all the rules of nature; natural selection, survival of the fittest, over-reproducing, population explosions, population crashes. Now that is an interesting story. At least for me.”

He is dismissive of the popular image of dogs and humans living in a mutually beneficial symbiotic relationship. “That is hype,” he says. According to the Centers for Disease Control there are approximately 4.5 million dog bites in the United States each year and 900,000 of those bites become infected. Dogs. The World Health Organisation says more than 95 per cent of rabies deaths in humans result from virus transmission through the bites of infected dogs, and an estimated 59,000 people die from rabies infections annually.

Dog bite

Dog bites account for 95% of all rabies infections in India and rural Africa according to the UN World Health Organisation.

In countries like India or in rural parts of Africa, infection rates are huge and treatment patchy – more than 95 per cent of human deaths occur in Asia and Africa. “You have to treat for rabies on day zero,” says Coppinger. “A day late and you’re dead.”

Besides the risk of infection from dog bites there are a whole host of other problems associated with domestic dogs, says Coppinger. “I live in a small town and we have a board of selectmen that meet every week. Fifty per cent of what they do is dog problems: barking, running loose, pulling little kids off bicycles, defecating all over the place. The neighbouring town is the same and I assume it is the same all over the country. Man’s best friend: what a stupid cliche.

Not for all the Tea in China

‘Canines run amok’ is an interesting alternative to the dog-friendly message of animal charities, breed clubs and pet magazines. Archaeozoologist Juliet Clutton-Brock returns balance to the argument. She would never get rid of her chocolate Labrador, despite the fact that he is “inbred” and costs “an absolute fortune” in veterinary fees.

“My dog is a partner, a friend, a companion, a substitute child,” she admits. “It is a terribly important relationship for people. I could not live without a dog and I’ve had one since I was eight years old.”

Clutton-Brock was fascinated by animals and archaeolgical digs during her early years in Rhodesia (now Zimbabwe) surrounded by ancient rock paintings and tribal artefacts. Persuaded to study medicine in her native England, she took courses in archaeology and zoology, gaining her PhD under the tutelage of famed archaeologist Frederick Zeuner.

Thirty years at the Natural History Museum provided her with plentiful opportunities to consider the early evolution of our relationship with canines. She has a pet owner’s passion for dogs and a background in their scientific study. Clutton-Brock says the modern relationship simply has its ups and downs. Some cultures treat the dog as a food animal. Others put appearance and breeding at a premium.

“It is a difficult situation,” she says. “To produce breeds like my chocolate Labrador, they must have selected for an odd colour and then inbred it to keep that colour. After 30 generations they may not be inbred on the pedigree but they are suffering from a genetic bottleneck. That is a dangerous situation for these dogs.

Dog weimaraner-puppy

Many pedigree breeds suffer the ill-effects of line breeding – genetic diseases can be in-bred.

“Of course a lot of them are physically abnormal, a complete disaster. The only way out for some breeds, like the chocolate Labrador, is to get rid of them. If you watch Crufts on television you see that it hasn’t moved much in the past 50 years. They are still bred to a standard shape and size. It is terribly wrong, biologically.”

Popular images of the ‘dog as companion’ are in fact a relatively new construct. Go back 150 years and most were kept as working dogs. Companion animals were the preserve of the rich and aristocrats. Dogs typically worked for their dinner as sheep dogs or rat catchers with close human contact and owner supervision, says John Bradshaw.

“We expect dogs now to be well behaved companions,” he says. “We expect them to be able to cope on their own in a way that our predecessors did not. They did not need to leave dogs on their own because there was always somebody at home. It was even expected that every now and then a dog would bite you.”

Pressure created by this situation has built a less than ideal platform for canine development. Though dogs and owners have coped remarkably well with modern life, there is scope to breed animals strictly for companionship, says Bradshaw.

“If you are a new owner and want to get a dog where do you go?” he asks. “You go to a pedigree breeder where there may be potential genetic problems, sometimes the dog is not as well socialised as it should be. If you go to a pet shop you get a puppy-farmed dog. If you go to a shelter you get a dog that may have been mistreated and show problems when you take it home. There is no guarantee anywhere of an ideal companion dog.”

Dog eyes

Dogs have become “non-human social support providers” for most owners in the west, according to James Serpell.

Dogs have become “non-human social support providers” for most owners in the west, adds James Serpell. “There are additional components to it, for instance the role of the dog as a guard dog, a protector or a watch dog,” he says. “People may not even be aware of it but they like it.

“They like to have an animal that is more aware than they are in case there is danger nearby. That has been a consistent value added element with dogs throughout history. The dog’s more acute senses, its sense of hearing, its ability to detect danger or something suspicious long before people can detect it.”

Complex roles such as military explosives detection or dogs that sniff out cancer are a significant advance, at least until humans can develop technology as sensitive as the dog’s nose, says Serpell. “It seems to me that there are a lot of new opportunities to exploit this ability and it has uses in medicine and detection. There is a world shortage of detection dogs, especially explosive detection. People want them.”

And yet the veterinary profession seems to have taken a back seat when it comes to promoting the benefits of more specialised forms of the canine relationship. “I’ve been struggling all my life to get the profession to acknowledge the value of these animals,” says Serpell. “They find it hard to get their head around the complexity of it. When you look at farm animals it is easy to see the benefit of people keeping them.

“When you look at a Pekingese or a Rottweiler it is much less easy, because what they contribute to their owner’s quality of life is not as measurable. It still exists but it is harder to measure in a reliable way.”

Too Close for Comfort

Generally this swing from working dog to companion has been the predominant trend in developed nations. The domestic dog’s use as a pillar of emotional support is perhaps the latest expression of that trend. For Anais Racca this has been distorted in a way that she finds slightly ominous. “We want things that are less useful, we don’t think ‘I want a dog because I feel lonely’ but maybe subconsciously that happens. Ownership becomes more and more for psychological reasons.”

“We have breeds that look more and more like little children,” she says. “Toy dogs often display an extreme level of what is termed ‘neoteny’, resembling not just infant, but foetal wolves. We create breeds that are so cute that they don’t exist naturally. I find it scary. We want things that are incompatible.”

Dog toy breed

Toy dogs often display an extreme level of ‘neoteny’, resembling foetal wolves.

In the final analysis we have to ask whether this level of psychological need is bad for dogs. Can we say with certainty what we expect to find when human neuroses or destructive drives are so closely tied together with our closest animal companions? “I think people need more information about what we can and cannot do,” says Racca sensibly.

The jury is out. We may look back on the past two centuries of pedigree breeding and showing as a period of human folly that irreparably damaged our relationship with man’s best friend. Or instead view it as an adaptive era where dogs were moulded in ways that best suited their changing role as companions rather than working dogs.

“If people were more aware and breeders were more careful, then it would be headed in a better direction,” Racca summises. “For instance, guide dogs or dogs that detect cancer, that is great and the bond is amazing. Dogs seek the presence of humans because of domestication, but in the end we have to respect the animal.

This is a previously published and updated article by Robin Fearon.

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