I’m quite hopeful you, as you read this, have a best friend.
If you don’t, however, you can pick up a best friend from a shelter not too far away: you can get a dog.
Dogs, called “man’s best friend” in a cliché and somewhat sexist statement, hold that special status in our hearts for a reason. Whereas horses can understand and work with humans, and while cats can see us as food and attention sources, dogs are starved for love and want to dole it out in equal – well, let’s admit it, greater – measure. But how did we get to this point? And why the heck are there so many breeds?
Let’s find out by delving into a pre-history that, with modern technology, is only now being discovered.*
This peer-reviewed gene analysis paper shows how researchers analyzed dog genomes of many breeds to determine that the well-beloved race all descended from gray wolves. Yes, that’s right, your beloved Butter Butt is 100%, genuine wolf.
In fact, the genetic clades (clades represent similarities in genomes, and the closer the clade the more similar the genes) show how closely related dogs and wolves really are. In one of the article’s images, the one that describes the haplotypes (or genetic groups) of dogs and wolves, several groups of dogs and wolves are about equally related to one another. Dogs and wolves are also capable of interbreeding.
This interbreeding seems to have been important during the domestication of the dog, as analysis of the mitochondrial DNA indicates multiple back-breeding events (i.e., when domesticated dogs interbred with wolves) added genetic diversity. It may also indicate multiple domestication events. Multiple events makes it really hard to pin down when dogs were domesticated, and even where! The paper I linked above seems to indicate the primary event happening in east Asia, but others (as summarized in this The Atlantic article) claim with what seems to be equal validity, that the event occurred in any number of places. There is a lot of evidence, however, favoring east Asia over other places.
While genetics has shown us what changed to cause the wolf ancestor to split into wolves and dogs, scientists still argue as to how or why those changes were implemented.
What does it take for domestication occur? This review article from Cell (trust me, it’s a high-level scientific journal) says there’s nothing certain about what makes an animal domesticated, and studied traits vary by species, breed, and situation. The sheer number of dog breeds with highly varying traits also leave us wondering what were the things ancient humans did that changed a wolf into a dog.
There’s only one thing we can be sure of: we absolutely needed friends. Humans gave dogs protection, food, and comfort in a harsh and ancient world even before the first agricultural revolution.
And, as you dog owners know, they gave all of that back ten-fold.
Though dog domestication happened something on the order of 15,000 to 30,000 years ago, the divisions of dogs into breeds happened much later.
And it’s the biggest genetic experiment to have ever happened.
From Mastiffs to Chihuahuas, from Shiba Inu to Australian Shepherds, they’re all dogs. Most breeds also didn’t exist until about 150 years ago, when it became a popular hobby in England to breed the perfect pup.
In fact, look at this map where the landmasses are adjusted for size based on the number of breeds from the area:
CRAZY FRIKKIN’ ENGLAND IS BIGGER THAN AFRICA, AUSTRALIA, and ASIA COMBINED. Also, sorry the map’s not zoomed in to see things well, but I couldn’t find a better image (I saw it for the first time at my dog trainer’s place).
In the late 19th century, the English – and, later, much of Europe – got into the whole idea that dogs were pets and could be bred. Now, I don’t want to be too presumptive, but Darwin published his Origin of Species in 1859, otherwise known as “pretty much at the beginning of the dog-breeding craze.” Was this scientific work influential in dog breeding? Did it inspire the middle-class hobbyists to begin creating dogs that had specific traits other than what were needed to do their jobs? There’s no proof, and it’s literally just something I’ve had in my head for a while, but I think it’s fairly coincidental that all of this happened at once.
But, as selective pressures brought about the differentiation between dog and wolf, human-enforced breeding measures brought about the breeds. We can see this still ongoing today as breed regulations change and new traits come into favor. For instance, when you look at the below picture of two chihuahuas, which one do you think is the correct by breed standard?
The answer is both are ok. Both the deer-headed (B) and apple-headed (A) Chihuahua are up to code, but the apple-headed dogs are more popular and more “desirable” (especially if you want more health problems). I take issue with this specific consumer choice due to those associated health issues, but whatever.
As dog breeding continues, issues associated with inbreeding have cropped up. If you choose to get a purebred dog, do your homework. Look up the lineages of the dog you’re considering, and maybe don’t get one descended from the top showdog (for AKC Pomeranians, it’s hard to get away from Prince Charming in your lineage, but I tried to keep greater diversity when I got my dog).
And, every time you pet your friend, remember that someone, thousands of years ago, was brave enough to pet a wolf.
About the Author: H.R.R. Gorman is a PhD chemical engineer with expertise in biotechnology and making drugs. Following science, Dr. G’s greatest passions are writing and history. She has a vicious attack Pomeranian named Hector, who she loves dearly. If you want to know more about this white-trash-turned-excessively-bourgeois maniac, you can go to https://hrrgorman.wordpress.com/.
*If you believe in the young earth theories or disbelieve evolution, I hope this article was interesting to you without being offensive. With or without evolution, it’s clear: dogs were designed to be our friends. 🙂