Q& A with Dr. Brian Hare and Vanessa Woods, authors of SURVIVAL OF THE FRIENDLIEST: Understanding Our Origins and Rediscovering Our Common Humanity (Random House, New York) and New York Times Bestselling authors of the 2013 book: THE GENIUS OF DOGS: How Dogs Are Smarter Than You Think (Oneworld Publications, U.K.)
Dr. Brian Hare, Biological anthropologist at Duke University, North Carolina, USA and Vanessa Woods, Science writer and researcher.
WHY WERE DOMESTICATED ANIMALS IGNORED BY SCIENTIST IN AN EFFORT TO INVESTIGATE THE PROCESS OF DOMESTICATION?
Domesticated animals were ignored for studies on intelligence, because it was thought that domestication made animals dull and stupid since they no longer had to make a living in the wild. As Jared Diamond wrote, brains presumably got smaller in domesticated animals because brains were a ‘waste of energy in the barnyard’.
CHARLES DARWIN WAS FASCINATED BY DOMESTICATION -- EVEN DEDICATING AN ENTIRE VOLUME TO THE PROCESS THAT HELPED READERS TO BETTER UNDERSTAND HIS THEORY OF BIOLOGICAL EVOLUTION. BUT HE DID NOT UNDERSTAND ITS UNDERLYING MECHANISMS.
Darwin had used domestication to beautifully illustrate the main principles of his evolutionary theory. After publishing The Origin of Species, he wrote The Variations of Plants and Animals Under Domestication where he used domestication to demonstrate that there was tremendous variation for natural selection to act on.
He spent years collecting examples of all the variation in traits created through artificial selection. But even Darwin was unsure of when, where and how animals first became domesticated. Ever since, domestication has been an evolutionary puzzle. But someone had figured out how domestication got started, and this gave us the chance to test our hypothesis. What we found changed how I thought about everything.
HOW DOES DOMESTICATION CHANGE AN ANIMAL'S APPEARANCE?
Domestication is usually defined as what an animal looks like. They change in body size – eventually leading to dwarf breeds like Chiuahuas and giant breeds like Great Danes. They have smaller heads than their wild cousins. Smaller canine teeth. Their hair changes color, losing the camouflage of wild animals. They are covered in random splotches of color, sometimes with a star mutation on the forehead. Tails curl upwards, sometimes in a full circle, like huskies, and sometimes in several loop de loops, like pigs. Their bones are more slender. They have floppy ears, which no animal has in the wild, except elephants. Their snouts are shorter. They have more babies. Not all domesticated animals have all of these traits. Instead, an assortment of these traits pops up in each domesticated species. It was incredible, how varying these traits were. They affected the appearance, behavior, and brains of domesticated animals.
FOR OVER A CENTURY NO ONE KNEW WHY THESE TRAITS APPEARED IN DOMESTICATED ANIMALS.
The only trait all domesticated animals have in common is that they are friendlier towards people than their wild cousins. But no one knew what connected these seemingly random traits, or whether they were connected at all. Some thought people bred for these changes deliberately. Biologist Eitan Tchernov thought smaller animals would have been easier to handle, and would have required less food. Geneticist Leif Andersson said that farmers bred animals with splotchy coats to reduce their camouflage when they wandered off. Zoologist Helmut Hemmer said domesticated animals had weaker visual and sensory system that lowered exploratory behavior, stress, and fear responses. But everyone tended to look at each trait associated with domestication individually and most considered them deleterious.
DO WE NEED TO RE-THINK OUR ROLE IN ANIMAL DOMESTICATION?
Everyone tends to agree that domestication was something that we intentionally did to animals; that we deliberately chose ‘animals more useful to humans than other individuals of the same species. Although researchers could not explain what unified the different traits of domesticated animals, they proposed a set of conditions that would predispose animals to domestication. [Jared] Diamond, [the popular science author and a professor of geography at UCLA], proposed that they had to be able to eat food that can be easily supplied by people, grow quickly and have a short birth interval, have a friendly disposition, breed easily in captivity, have follow the leader dominance hierarchies, and remain calm in enclosures or when faced with predators. Diamond insisted that to qualify for domestication, an animal had to meet all these criteria. Other researchers added that suitable animals should be polygamous, readily controlled with a small home range, and live in large groups with the males.
SO WHAT’S YOUR BEEF WITH DIAMOND’S CONDITIONS FOR DOMESTICATION?
These criteria exclude a lot of animals. Of the world’s 147 large mammals (over 100 pounds) with the potential to be domesticated, only 14 were domesticated, and we relied on only five of those for any length of time (sheep, goats, cows, pigs, and horses). Smaller animals were also domesticated - wolves were one of these – but they were still relatively few.
This school of thought became a dominant explanation for why different animals were domesticated, helping to usher some societies into agriculture, while others remained hunter gatherers. According to this view, domestication is a human centric process where animals come under our control and become economically useful.
This human centric definition of domestication might explain things from a cultural and economic perspective, but not from a biological one. And there is one big problem - dogs. Wolves do not fit the essential criteria. Their food is difficult for people to supply, they definitely panic in enclosures, and while they are not nasty, they definitely bite when threatened.
DO YOU BELIEVE THAT ICE AGE WOLVES DOMESTICATED THEMSELVES IN THE WILD, A PROCESS THAT FIRST LED TO PROTO-DOGS OR WOLF-DOGS AND THEN ULTIMATELY TO DOMESTICATED DOGS, AND IF SO THEN WHAT WAS THE ROLE, IF ANY, OF HUMANS IN THE PROCESS?
Yes, [I do believe that wolves domesticated themselves into proto-dogs or wolf-dogs].Genetic analysis show us that wolves, 15-30,000 years before we became agriculturalists, [were already becoming domesticated living alongside hunter-gatherers]. When we arrived in Eurasia 50,000 years ago with our shiny projectile weapons, we wiped out every predator of the Ice Age. Wolves back then were bigger than they are now. There was no way anyone was going to take a puppy back to camp, raise it, and leave it with their kids.
We did not choose wolves, wolves chose us because they realized we make a lot of trash. Even today, hunter gatherers throw their garbage and go to the bathroom outside camp. As our population increased, there would have been more tempting morsels for a hungry wolf to feed on at night. Discarded bones would be nice, but people poop is equally delicious. Because we cook our food, our poop is kind of like an energy bar.
The least fearful wolves would have been the most successful dumpster divers. They also had to be friendly. Given the way we behaved towards other predators, any aggressive wolf would have been killed on sight.
After only a few generations, these super friendly wolves would have started to behave differently, and also look different to regular wolves. Just like the foxes, there would have been slight variation in coat color. Later they would have floppy ears, smaller snouts, and smaller teeth. Eventually, these proto-dogs would reveal that they had an extraordinary ability – they could understand us in a way other animals could not. Wolves could use the social gestures of other wolves, but they were too busy running from us to pay attention to our gestures. With their fear of people replaced with an intense attraction, these social skills could suddenly be used with new flexibility – towards us. An animal that could respond to our voices and gestures, now that was a good hunting partner.
We did not domesticate dogs. They domesticated themselves.
IN SURVIVAL OF THE FRIENDLIEST, YOU STATED THAT BELYAEV’S WORK PREDICTS THAT OUR INCREASING POPULATION WILL BE ENOUGH TO DRIVE THE NEXT GREAT SELF-DOMESTICATION EVENT THROUGH NATURAL SELECTION.
[Yes], because urban species must live close to humans, the selection pressure will be on friendly, non-aggressive individuals, simulating the conditions for Belyaev’s experiment