10 amazing facts and theories about dogs

Image credit: Flickr/JASEN MILLER

I saw an amazing documentary on Netflix over the weekend about the genetic makeup of dogs and the bond that has evolved between humans and our canine friends.

The Nova program is titled "Dogs Decoded," and even though I've had dogs for much of my life and think I know them fairly well, I learned some interesting things watching this PBS production.

Below, for your education and entertainment, are 10 amazing facts and theories about dogs, including two I made up.

10 amazing facts and theories about dogs (including two I made up)

* There are nearly half a billion dogs in the world.

* Mitochondrial DNA sequences show that dogs are descended from gray wolves. (This rules out theories that the wide variety of dogs in the world may be in part due to genetic contributions from numerous canine ancestors such as the African wild dogs, jackals or coyotes.)

* Based on bone studies – particularly of canine skulls – scientists estimate that wolves began to be domesticated 12,000 to 13,000 years ago. But mitochondrial DNA puts domestication 100,000 years ago or more.

* Wolves, like ancient humans, were carnivores who hunted in groups during daylight. Scientists believe this may have spawned a symbiotic relationship -– “we became much better hunters with dogs,” says one researcher -- that not only gradually enabled domestication, but increased human population.

* Dog domestication may have paved the way for a monumental change in human lifestyle. Some researchers believe without dogs to help herders move and guard their flocks, agriculture may never have developed and humans would have remained hunter-gatherers.

* Despite a common misperception whose origin was traced back to the art world, dogs cannot play poker.

* Humans are the only species that uses pointing as a gesture of communication. And dogs are the only other species that understands it. Research with wolf puppies showed that they don’t understand human pointing, so it is a skill dogs developed.

* A border collie in Austria named Betsy can understand nearly 340 words.

* A ongoing domestication experiment on silver foxes in Siberia indicates that when you breed for non-aggression, many other physical traits associated with dogs – floppy ears and curlier tails, for example – follow along.

* Stan, the dog that stars in the Disney Channel show "Dog With a Blog," is a Six Sigma black belt.

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