Julien d’Huy, of the Pantheon–Sorbonne University in Paris, talks about the use of evolutionary theory and computer modeling in the comparative analysis of myths and folktales, the subject of his article in the December 2016 Scientific American. We'll also hear from Nick Matzke, an evolutionary biologist currently on a fellowship at the Australian National University in Canberra, about how to use phylogenetic analysis to create relatedness trees. 

Steve Mirsky:  Welcome to Scientific American’s Science Talk, posted on November 15, 2016. I’m Steve Mirsky. On this episode -

Julien d'Huy: Myth, an organism are formed by discreet heritable units which evolve over time.

Mirsky: Myth, an organism are formed by discreet heritable units which evolve over time. That's Julien d'Huy. He is a doctoral candidate in history at Pantheon Sorbonne University in Paris. He uses evolutionary theory and computer modeling in the comparative analysis of myths and folktales. It's very interesting stuff and he has an article about it in the December issue of Scientific American. Julien d'Huy was kind of enough to provide about 20 minutes' worth of audio. Unfortunately, my ear is not good enough to catch everything that he was saying, so what I did was go through the audio and pick out a few sections that I thought were clear enough for my American ear to follow. I'll try to fill in some of the rest with the idea here.

The basic idea that he explicates in the article is that we can track the evolution of myths and folktales with the same techniques that we use to establish evolutionary relationships and evolutionary history. It's very interesting stuff. Imagine a giant game of telephone. We probably all played telephone in school when we were kids. Maybe there were 20 people. You start at one end and they whisper in each other's ear and it comes out the other end and you see what happened to it. Imagine that game played over thousands or even tens of thousands of years with thousands or even millions of people. The striking thing to me is just how much of the original story actually is maintained after all those iterations.

d'Huy: Myth, an organism change over time. This is a most important thing. Myth, an organism, are formed by discreet _____ units which evolve with time. Most species are myth diverged geographically and _____ the more distant the genetic relationship is. If you agree with these two proposals, you can use the genetic tools to study myth _____.

Mirsky: Let me just tell you very briefly how he begins the article. He talks about the Greek version of a familiar myth. It starts with Artemis, the goddess of the hunt. Artemis demands that Calisto and her other handmaidens take a vow of chastity. Zeus tricks Calisto into giving up her virginity and she gives birth to a son named Arcas. Now Zeus's jealous wife Hera turns Calisto into a bear, banishes her to the mountains. Meanwhile, Arcas grows up to be a hunter. One day, he happens on a bear that greets him with outstretched arms. He doesn't recognize that this bear is his mother so he takes aim with his spear, but just in the nick of time, Zeus comes to the rescue and then because he's Zeus and he does things like this, he transforms Calisto into the constellation Ursa Major, the great bear, and places Arcus nearby as Ursa Minor, the little bear. So that's from ancient Greece.

Meanwhile, in the Iroquois culture of the Northeastern United States, they have this story. Three hunters pursue a bear. The blood of the wounded animal colors the leaves of the autumnal forest. The bear then climbs a mountain, leaps into the sky. The hunters and the animal become the constellation Ursa Major.

Then again among the Chukchi, a Siberian people, the constellation Orion is a hunter who pursues a reindeer, Cassiopeia.

Meanwhile, in the Finno-Ugric tribes of Siberia, the pursued animal is an elk and takes the form of Ursa Major.

d'Huy continues, "The animals in the constellations may differ, but the basic structure of the story is pretty much the same. These sagas all belong to a family of myths known as the cosmic hunt that spread far and wide in Africa, Europe, Asia, and the Americas among people who lived more than 15,000 years ago. Every version of the cosmic hunt shares a core story line. A man or an animal pursues or kills one or more animals and the creatures are changed into constellations."

What d'Huy did was use phylogenetic software that's used for evolutionary tree building to analyze the extant versions of these myths and see how related they are. To give you an idea how you do that, I'm going to go back to a podcast that we ran last December with Nick Matzke, an evolutionary biologist who also used the phylogenetic software in an unusual and interesting way. He analyzed the relationships among some 60 bills in various state legislatures around the U.S. that all deal with trying to disrupt the education of evolutionary theory in our public schools. We have these 60 bills which are clearly quite related to each other. Somebody writes a bill in one state and maybe it almost gets passed so somebody in another state pretty much copies the bill and makes a few little changes to it. What Matzke did was plug all these bills into his software that analyses usually genetic sequences and established a relationship tree among all these bills. I'll let him explain how he did that and then I'll be back with more from Julien d'Huy.

Matzke: I went to Berkeley and got a PhD. I studied phylogenics, which is the study of phylogenies – phylogenies of the evolutionary trees, showing the relationships of different species through common ancestry. I learned a lot about that and then I went off to do a post doc in Tennessee. In Tennessee, they ended up passing one of these bills in 2012. We had always talked about – we're like, "These bills that look like they're just being copied and modified, we should do a phylogeny at some point – do an evolutionary analysis of them." It became clear this year that there were enough of these bills to do a phylogeny. It had gotten up to being about 60 bills so that we can show how these policies have evolved – how the anti-evolution policies have evolved through time. I dropped everything back in July and August and for about a month, crashed through this analysis where I took all those bills, lined up all the text, coded all the characteristics – all the variations between these texts – and then ran them through the standard phylogenetic analyses that we use for DNA. We use them for dinosaurs. They get used to study virus evolution. Those same programs can be used on texts that have been copied and modified. That's basically how this paper came about.

Mirsky: What did you actually uncover when you did this laborious text analysis?

Matzke: There's a couple main results that are sort of the technical results of this. Part of the point was, yeah, ha-ha, creationism evolves. I think it's a useful point to make, but there were some technical results which was, "How strong is the signal of common ancestry when you have something –" with animal species, we know they have common ancestry. That's been immensely well-established. But if you have a collection of textual documents, you don't know starting out how much of that is due to copying and modification and how much of it is due to independent composition by different writers and things like that.

Mirsky: Again, these are bills in various legislatures around the country.

Matzke: Exactly. Every legislative session in every state, which is either every year or every two years, hundreds of bills get proposed on all sorts of topics. Each one of those gets published. These days, they all go online when they're published. So the publication just means the bill has been introduced by somebody. So you have that text and it has a date on it. If you Google, "Creationism legislation database," you'll see this database of all these bills that have been proposed and sometimes passed through the years. I took those and – yeah, you take those texts and you do this kind of exhaustive analysis where you line up all the characteristics and say, "Does it have this word? Does it not have this word? Does it use this phrase? Does it not use this phrase?" Those are just characteristics that when a text is copied – those characteristics get copied – and on occasion they get modified. By tracing which bills share these variants, you can tell what the copying history is.  

Mirsky: In his article, d'Huy talks about the fact that Jung argued that these myths are part of the collective unconscious. But d'Huy says that the dissemination of cosmic hunt stories around the world can't be explained by such a universal physic structure because if that were the case, they would be everywhere. But they're not everywhere. They're nearly absent in Indonesia and New Guinea. They're very rare in Australia, but they're present on both side of the Behring Strait which geologic and archaeological evidence indicates was above water between about 30,000 and 15,000 years ago. The most credible working hypothesis therefore is that Eurasian ancestors of the first Americans brought these myths with them over the Behring Strait.  

d'Huy: It's a fact that similar and complex myths could be recognized in Eurasia and America shows that evidence of shared ancestry could be found around 10,000 to 50,000 years ago. Because this myth could ____ ____ immigrants from northeastern Asia when Beringe was above sea level.

Mirsky: When Beringe was above sea level. So to calculate his tree, d'Huy used 47 versions of the cosmic hunt story and 93 myth themes within those stories.

d'Huy: Following the biological model of a tree shows the relationships among various biological species. _____ ____ trees showing the relationships among various versions of the same myth among many traditions. By this way, I can test hypotheses about human prehistory. The process is explaining the current geographic distribution of the myths ______.  

Mirsky: One of the interesting things about this work is that we've always been able to look at fossils and try to establish evolutionary relationships there by comparing what was actually left in the ground. Now we can look at genetic sequences and try to establish relationships, but behaviors and ways of thinking are often lost because they don't leave concrete evidence. Because we can examine these ideas, and folktales, and myths, and then map those using the same instruments that we use to map evolutionary history, we might actually be able to go back in time and get into the minds of our ancestors and that's pretty interesting stuff.

d'Huy: A careful use of the ________ methods give us an opportunity to shed new light on the beliefs of our ancestors. For instance, on the very odd belief of a master of animals I have one final point. In several of my databases, I have found a strange and strong signal just after the moment that humanity left Africa.

Mirsky: He's found a strange and strong signal just after the moment that humanity left Africa.

d'Huy: There could be many reasons for this. One of them is that it could be an ______.  

Mirsky: It could just be some noise.

d'Huy: But it could also be a sign of a cultural contact between homosapiens and a previous human species, maybe Neanderthals. It's fun, isn't it?

Mirsky: But it could also be the sign of a cultural contact between homosapiens and a previous human species, maybe Neanderthals. And then he finishes – and I agree – "It's fun, isn't it?"

Mirsky: That’s it for this episode. Get your science news at our website, www.ScientificAmerican.com, where in the December issue you can read the story about the evolution of myths by Julien d'Huy. And follow us on Twitter where you’ll get a Tweet whenever a new item hits the website. Our Twitter name is @SciAm.  For Scientific American Science Talk, I’m Steve Mirsky. Thanks for clicking on us.

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