Monday, January 26, 2015

Why Wolves Became Dogs


Why Wolves Became Dogs

PHOTO: Wolves are at least as tolerant and socially attentive as dogs.
There's a good reason why wolves became human companions long before domestic breeding turned them into everything from Great Danes to poodles, scientists in Vienna say.
They wanted to be our friends because underneath that furry hide they were a lot like us.
For several years, researchers at Vienna's University of Veterinary Medicine have been studying wolves that have been raised in captivity just like domesticated dogs, to see how they differ from the canine pets that are in so many of our homes. They have even established the Clever Dog Lab and the Wolf Science Center.
In a study published in the journal Frontiers in Psychology, researchers Friederike Range and Zsofia Viranyi offer their "Canine Cooperation Hypothesis."
According to the hypothesis, ancient wolves already possessed at least three social skills that made them suitable for human companionship: They were tolerant, attentive and cooperative.
Just like dogs.
And they were very social, running in packs, just like humans.
In the latest in a series of experiments, the researchers found that wolves can learn if a human has food, where it is stashed, and even if the human is just fooling.
If the human hid it behind a shed, the wolf went right to it, apparently because it had observed the human's actions. Dogs that participated in the same experiment were more likely to sniff their way to the food, not relying as much on their powers of observation.
PHOTO: A gray wolf is shown in this undated photo.
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PHOTO: A gray wolf is shown in this undated photo.
Wolves also proved to be highly attentive, even to the point of figuring out what the researcher was going to do next just by observing her head movements and where she was looking.
And not surprisingly, the wolves liked to cooperate with the researchers, which made them ideal hunting partners sometime between 15,000 and 34,000 years ago.
Eleven North American grey wolves and 14 young dogs, all raised in similar circumstances, took part in the experiments. These were not wild wolves, so some would question whether their performance was based on genetics or learning from their feeders.
Asked about that in an email, Range said, "Of course the attentiveness towards humans can be a learned response towards the human activity or rather they can probably concentrate on humans because they are not afraid of them."
In that case it may be that social tolerance -- a key trait shared by both wolves and dogs -- helped the wolves learn from their human friends.
The study was based mainly on animal-to-animal interaction, and in a number of cases the wolves outperformed the dogs by being more attentive to humans, "one skill that has been suggested to be a precondition of successful cooperation," the study notes.
Many other studies suggest that wolves were domesticated because they were useful to our ancestors, first as hunting partners and later as workers around the farm.
Beyond that, not a whole lot is known about how this all came about. Experts can't even agree on where the first dogs originated.
Four years ago, an international team of scientists led by evolutionary biologist Robert Wayne of the University of California, Los Angeles, published a study in the prestigious journal Nature claiming that genetic data showed that dogs originated in the Middle East.
A year later Swedish scientists claimed they had "proof" that the wolf ancestors of today's domesticated dogs could be traced to East Asia.
Two years later, UCLA's Wayne and colleagues published another study, this time in the prestigious journal Science, saying new evidence showed that dogs originated in Europe, not East Asia or the Middle East.
Yet a year earlier, Wayne told a science conference in New York that the genomes from wolf breeds from each of those areas turned out to be quite different from the dog genome.
The researchers had expected one of those genomes to be a better match with the dog genome, proving once and for all where the first dogs came from. But there was no joy there.
Wayne has suggested that the progenitor of Fido probably no longer lives on this planet, and may have gone extinct thousands of years ago.
That fits well with a study last year from the University of Chicago Medical Center that found dogs are much more closely related to each other than wolves, so it's likely that the domestication of the wolf was a gradual process, possibly dating back to 34,000 years ago.
At this point, no one knows for sure.
And that's kind of the story of domestication, as incomplete as it is.
A few years ago top scholars from around the world met at the National Evolutionary Synthesis Center to discuss what they thought they knew about domestication processes, not just of wolves but of all sorts of plants and animals.
They ended up with more questions than answers, not an uncommon predicament in science.
For example: There are about 200,000 wild flowering plants around the world, so why have so few been domesticated?
Cattle and pigs once roamed wild, but there are 148 species of large wild mammalian herbivores or omnivores, so why have only about five been domesticated?
All that suggests that once a genetic code has been established, there's not a lot we can do about it. You can throw a saddle on a zebra and call it a horse, but don't even try to ride it.
One conclusion from that meeting: "It almost certainly is not true that people can step in and completely remodel through artificial selection an organism shaped for millennia by natural selection."
And that brings us back to dogs.
Although experts disagree over when it all started, the era of the modern dog, according to many studies, started about 12,000 year ago. Yet in that relatively brief period of time breeders have produced an enormous range of changes in the dog genome. How could that be possible if it is so difficult to "remodel" an organism?
Perhaps the Vienna team has an answer. No matter when or where it started, the wolf came with a set of social skills that made it an ideal companion for humans struggling to survive in a primitive world. It was ready to adapt.
end quote from:
http://abcnews.go.com/Technology/wolves-dogs/story?id=28458597&singlePage=true

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