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Comment by Emily & Daisy on October 15, 2012 at 10:53pm

John-  Lol about the explanation why they have short legs. Thanks for adding all this great info in the comments everyone! That was really cool. :)

Comment by John Wolff on October 15, 2012 at 3:03pm

@Julia, it's Diamond, "Guns, Germs, and Steel".

This website is kinda technical. 

http://www.angelfire.com/in/wolfblud/canineevolution.htm

They study the mitochondrial DNA because it's inherited only through the mothers (mitochondria are those tiny energy organelles inside cells; they have their own DNA, and were once free-living bacteria, now commensal symbionts).

They seem pretty sure that dogs come from wolves, not coyotes or foxes or other canids.

We, of course, know that corgis are a gift from the faeries.  The whole wolf thing is just a cover story. Faeries like their privacy.

 

The evolution of the domestic dog
The earliest remains of the domestic dog date from 10 to15 thousand years ago²¹; the diversity of these remains suggests multiple domestication events at different times and places. Dogs may be derived from several different ancestral gray wolf populations, and many dog breeds and wild wolf populations must be analysed in order to tease apart the genetic sources of the domestic dog gene pool. A limited mitochondrial DNA restriction fragment analysis of seven dog breeds and 26 gray wolf populations from different locations around the world has shown that the genotypes of dogs and wolves are either identical or differ by the loss or gain of only one or two restriction sites²². The domestic dog is an extremely close relative of the gray wolf, differing from it by at most 0.2% of mtDNA sequence^15,22,23.

In comparison, the gray wolf differs from its closest wild relative, the coyote, by about 4% of mitochondrial DNA sequence¹⁴ (Fig. 4). Therefore, the molecular genetic evidence does not support theories that domestic dogs arose from jackal ancestors²⁴. Dogs are gray wolves, despite their diversity in size and proportion; the wide variation in their adult morphology probably results from simple changes in developmental rate and timing²⁵.

If you like this stuff, also google "belyaev", the famous silver fox domestication experiments.       Belyaev

Comment by Tomahawk and Fences on October 15, 2012 at 11:12am

I know of one breed of dog that was in the Americas before Columbus called the Xoloitzcuintli, aka the Mexican hairless dog. They were used as companion animals, bed warming, food, and sacrificial offerings by the Aztecs and the Mayans. I believe they go back 3,000 years and are considered one of the oldest breed of dogs. 

I actually got to meet one on Saturday at a dog fair benefiting local rescue organizations. That sucker had a bottle of sunscreen just for him.

I know if I was crossing the Bering Strait to a whole new world, the first thing I would put in my sack would be my little four legged friend.

Comment by Julia on October 15, 2012 at 2:10am

I'm curious to know if there were domestic dogs in the New World pre-Columbus. As far as I know llamas and guinea pigs were domesticated, but they may have been the only ones, unless there were dogs.

Which brings up another book, the name of which I can't think of right now. The premise was that successful societies were in areas with large domestic animals - Europe, Southeast Asia, Northern Asia. The water  buffalo, the cow, the horse. These allowed for better agriculture. I'm sure the domestic dog helped a lot, as well. The New World, on the other hand, without these domestic animals did not develop large scale successful agriculture and industry. This is why I wonder about dogs in the Americas.

Itty-bitty dwarf dogs might not be all that helpful in developing a society, but they sure have a cute smile :)

Comment by John Wolff on October 14, 2012 at 1:12pm

Isn't the mascara and the black gum line written into the breed standard for corgis?  They don't look like they're smiling by accident.

Next time somebody asks what happened to your dog's legs, tell them this, it will shut them up:  an expressed  fibroblast growth factor 4 retrogene is associated with chondrodysplasia in domestic dogs. 

The leg-dwarfing mutation that creates the short legs is the same in all 16 domestic breeds with short legs.  It is obviously a one-time event.  Somebody long ago found a dwarfed puppy, thought it was cute, and they bred it.  Dachshunds, bassets, beagles, corgis, etc. all have this tiny piece of common ancestry.  

Interesting technicality:  a retrogene is an extra copy of a gene already present in the genome.  The retrogene that causes the leg dwarfing has a 1-base silent point mutation (just 1 bit changed, makes no difference) that is not present in the source gene in dogs, but is present in wolves from eastern Europe and the Middle East.  It's a molecular fossil of their lupine ancestry.  Don't let the short legs fool you.  They're little wolves.  Just give them the food, and nobody gets hurt.