Everything Everywhere Daily: History, Science, Geography & More - The Domestication of Dogs (Encore)

Starting point is 00:00:00 The following is an encore presentation of Everything Everywhere Daily. It's been said that a dog is man's best friend. This might be true, but why? How is it that this particular animal developed such a special relationship with humans? How did they go from being wild to domesticated? And how is it there are so many different breeds of dogs that all came from the same original source? Learn more about the domestication of dogs and how it happened on this episode of Everything Everywhere Daily. What if your perceptions about the past were wrong?

Starting point is 00:00:47 ThruLine is a podcast that takes you back in time to uncover the parts of the story that may have gone unnoticed. It effectively turned day into night. And how it shaped the world now. Time travel with us every week on the ThruLine podcast from NPR. The story of humans and dogs goes back to before the dawn of civilization when our ancestors were hunters and gatherers. Dogs were the very first animal ever domesticated by humans. They were domesticated long before horses, cattle, sheep, or even cats. Whenever we go back that far, details become sketchy because we have no written or even oral records.

Starting point is 00:01:30 It was the onset of DNA analysis that gave us our first real glimpse of when dogs were first domesticated and where they probably came from. The domesticated dog has the scientific name Canis Lupus Familiaris. One of the most shocking things about domestic dogs that not everyone knows is that all domestic dogs are the same species. As radically different as dog breeds are, they are all fundamentally the same thing. A 120-pound Irish wolfhound is the same species as a five-pound chihuahua. This is seen in the fact that different breeds of dogs can interbreed with each other. One of the definitions of a species, although it can be a bit fuzzy around the edges, is the ability to breed with other members.

Starting point is 00:02:13 of the same species. Birds might look as different from one another as dogs do, but birds don't interbreed. The closest living wild relative of domestic dogs are gray wolves or timber wolves. Today, they can be found in North America and northern Eurasia. The point when dogs genetically split off from wolves occurred about 20 to 40,000 years ago. This was around the last glacial maximum. This period doesn't necessarily represent the point where dogs were domesticated, however, because that occurred later. Everything I just described were able to know via genetic evidence. It might be vague, but it is solid. Where there is a great deal of debate is how, when, and where dogs were domesticated. There are several theories on the domestication of dogs, and most of them

Starting point is 00:02:58 suffer from the same dearth of evidence. The when is one of the least contentious things. The domestication is generally believed to have occurred around 15,000 to 11,500 years ago. That 11,500 year point is one that's come up before in many episodes, as it was truly a turning point in the history of the earth and of the human race. It was the end of a period known as the Younger Dryas, but I will leave that to another episode. Where the domestication took place is where the real debate is. One camp holds that dogs were domesticated somewhere in East Asia around 12,500 to 11,500 years ago. Another theory holds that the domestication event took place in Europe around 15,000 years ago.

Starting point is 00:03:43 These two theories are not necessarily mutually exclusive with each other. If there were two independent domestication events, then the Asian variant probably migrated west and supplanted the European domesticated dog. And yet there's another theory that dogs were domesticated in Central Asia and spread both East and West simultaneously. And finally, a study published in 2021 claims that dogs may have been domesticated in Siberia as far back as 20,000 years ago.

Starting point is 00:04:10 If this is true, it might explain how domesticated dogs made it to both Europe and the Americas during the last ice age. The earliest evidence we have of dogs and humans living together was found in Europe. There was a grave site found in Bonne-Obercastle, Germany that dates back to 14,000 years ago. In China, a grave with a domesticated dog was found that dates back about 8,000 to 9,000 years ago. And the earliest evidence of dogs in the Americas comes from a grave found in Utah, which dates back about 11,000 years ago. These dates of dog and human burials puts a lower bound on when we can be certain domestication occurred, but we have no idea what the upper bound is and why there's so much uncertainty. One problem with excavating remains in southern China, for example, is that a hot, wet climate

Starting point is 00:04:56 isn't good for the preservation of fossils. So basically, we know roughly when they were domesticated, but we don't know where. The next big question is how and why dogs were domesticated. Here we can really only speculate, but the standard story goes something like this. Early humans were out hunting, processing their kill, or perhaps they were sitting around a fire eating the rewards from that day's hunt. Some wolves, which, for whatever reason, had no fear of humans, would try to sneak up and take some of the leftovers and scraps. Over time, humans became comfortable with these wolves, and the wolves found this to be a winning strategy. Hanging out with the humans was easier than being low on the totem pole in a wolf pack. Humans fed you. You could stay next to a warm fire, and in return, all you had to do

Starting point is 00:05:41 was help warn the humans of danger and maybe help them drive animals during a hunt. The key here is that being docile and not afraid of humans was a trait that the dogs had. As the dogs bred, usually with other docile dogs that they were hanging out with amongst the humans, this trait would have been passed down. Dogs would eventually be born and grow up amongst humans. An interesting side note, while domesticated dogs are related to wolves, they have been interbreeding with wolves for thousands of years. Remember when I said that one definition of a species is if the animals can interbreed? Well, I also said that the lines can sometimes be fuzzy, as is such a case. You could argue that wolves and dogs are still the same species for this reason, although they are very different.

Starting point is 00:06:28 Anyway, one of the odd things about the gray wolf is that not all of them are gray. occasionally there are black wolves and sometimes white wolves. Geneticists believe this mutation may have come from domestic dogs who bred with wild wolf populations. There are even more of these non-gray wolves in North America than there are in Eurasia, indicating that domestic dog wolf interbreeding might have occurred more frequently there. Another interesting thing about the ancient remains of dogs that have been found with humans is the size of the skeletons can vary considerably. Very small dog remains have been found as well as very low.

Starting point is 00:07:02 large dog remains. This would seem to be evidence of dog breeds. However, there's a DNA test that is run to genetically distinguish dog breeds called the SNP or single nucleotide polymorphism test. Using this genetic test on the ancient remains that have been found, the different size dog remains do not seem to be different genetic breeds. One of the biggest changes to humans was also a huge change for dogs, the creation of agriculture. Humans became sedentary. Humans became sedentary. and this changed dogs as well. Dogs had been naturally selecting their own traits to live with humans. This was replaced with humans purposely breeding the traits that they wanted,

Starting point is 00:07:42 this including size, docility, and intelligence. Dogs began to be trained to perform particular functions, such as herding sheep, goat, and cattle. Dogs also managed to provide protection against wild animals who might otherwise try to eat animals or crops that were being grown by farmers. Dogs were also assigned the task of killing rodents on many farms, even though this was a service that was later assigned to domesticated cats, but that's another episode. In the Americas, dogs were some of the only domesticated animals in many civilizations.

Starting point is 00:08:13 Dogs were the only pack animals available north of the Andes where they had llamas. Dogs of Polwood was known as a travois, which was just two sticks that dragged on the ground. Dogs were the primary method of moving goods and supplies when native people had to migrate from one camp to another. Most dogs were still not kept as pets as we think of them today. They were working animals in a world where almost everyone lived on farms. In fact, it's estimated today that three quarters of all domestic dogs worldwide do not live with any specific humans, but rather live communally amongst humans. I've personally seen this all over the world where dogs who don't seem to have any obvious

Starting point is 00:08:50 owners will just run around the streets of a city. One of my first international trips I ever made was to Argentina, and I remember seeing homes with elevated metal baskets outside their house. I had no idea why they did this and eventually someone told me it was so the dogs wouldn't get into the garbage. Up until about the middle ages, the domesticated dogs that existed would certainly be recognized as dogs, but what you didn't see were the wide variety of breeds that exist today. Everything was probably what we would define as a mutt, with some exceptions for highly specialized dogs such as water dogs. In fact, almost all breeds of dogs can only be dated back about 500 years.

Starting point is 00:09:28 and the majority of breeds less than 150 years. Certain categories of dog breeds, such as toy dogs, would have served no real function prior to the modern era. In particular, the 19th century saw massive growth in selective breeding for particular phenotypes. As dogs can reach sexual maturity within a year, it's possible to rapidly develop breeds with certain traits if it's the intent of the breeder. The World Canine Organization, which is an international association of National Cal clubs, recognizes 360 different dog breeds.

Starting point is 00:10:00 There are still new dog breeds being registered today. In just the last couple of years, the American Kennel Club has recognized the Barbette, a very hairy dog from France, the Azawak, a hunting dog from West Africa, and the Dogo Argentino, a muscular hunting dog from Argentina. So while dogs and humans have had a long relationship with each other,

Starting point is 00:10:19 the question still remains, why dogs? Why were dogs the first animal to be domesticated, and not something like a lion or horse. There are several attributes which wolves had, which made them rather natural candidates to cozy up to humans. For starters, wolves are naturally social animals. Wolves usually live in a pack and are accustomed to interacting with other creatures. This ability naturally lent itself to socialization with humans.

Starting point is 00:10:43 Other animals like lions tend to be more solitary. Second, wolves are predators. Animals that are prey tend to be much more skittish and run away from anything that approaches them. A predator would be much more likely to approach another animal or show curiosity. And finally, wolves are the right size. An animal like a lion would have probably scared even a good-sized group of humans if it approached them. A solitary wolf, however, isn't as much of a threat.

Starting point is 00:11:09 Even a small group of humans could probably take on a wolf, especially if they have spears. Anything smaller than a wolf probably wouldn't have been noticed. I'll end with a very interesting experiment that was conducted in Russia to determine just how fast it would take to create. domesticated dogs. Russian scientist Dmitri Believ began an experiment in the early 1950s, where he was trying to breed a domesticated fox from an initial population of wild silver foxes. And I should note that there was no such thing as a domesticated fox before this experiment started. For over 50 years, the experiment ran, and each generation was selectively bred based on how little they feared humans. By the early 2000s, they had a population of foxes that basically showed no fear of humans at all.

Starting point is 00:11:55 They would lick the hands of humans, wag their tails, and exhibit many of the same behavioral traits that domesticated dogs do. This isn't to say that they're a totally domesticated animal yet, but their behavior has changed radically compared to their ancestors just 50 years earlier. The behavior wasn't the most interesting thing, however. They also started to show changes physically. They had tails that were more curly. their ears started to be more droopy, and their coats began to develop spots. All of these are traits often found in domesticated animals of all types. It's believed there might be a collection of genes that work together,

Starting point is 00:12:31 and if you breed for behavior, you'll also get these physical changes. Wherever and whenever dogs were originally domesticated, what is undeniable is that dogs and humans have grown together and that humanity's four-legged friends have played a role, however small, in the creation of the world that we have today. The executive producer of Everything Everywhere Daily is Charles Daniel. The associate producers are Peter Bennett and Cameron Kiefer. I wanted to give a big thanks to everyone who supports the show on Patreon.

Starting point is 00:13:03 Your support helps me put out a new show every day. And if you're interested in Everything Everywhere Daily merchandise, Patreon is currently the only place where it's available. And if you'd like to talk to other listeners of the show and get notified of future episodes and projects, please join my Facebook group or Discord server. Links to everything are in the show notes.

Everything Everywhere Daily: History, Science, Geography & More - The Domestication of Dogs (Encore)

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