Pod Insights Short Wave A Lock of Hair Could Rewrite Knowledge Of The Inca Empire About this episode The Inca Empire in South America was one of the most powerful pre-Columbian societies. It was known for the architecture of Machu Picchu, an extensive road network and a system of terraces for agriculture. The society also kept records known as khipu, which involved a system of tying knots to encode sophisticated information.
Literacy in this form of writing was assumed to be something that only the highest levels of Inca society could do. But NPR science correspondentNell Greenfieldboyce https://www.npr.org/people/4494969/nell-greenfieldboyce shares how a new analysis of a cord made out of human hair may change that assumption.
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0:23 Regina Barber? Hey, Short Wavers. Regina Barber here. And today on the show, we are diving into an unusual part of life in the Inca Empire. In the 15th and 16th centuries, this empire ruled over 10 million people in South America, covering modern day Peru, Ecuador, Bolivia, northwest Argentina. At the time, it was the largest empire in the world.
0:44 Speaker 02 So as you can imagine, it had things like an extensive network of roads, impressive architecture. It had a whole bureaucratic system to keep track of everything that was going on.
0:54 Regina Barber? That's NPR science correspondent Nell Greenfield. Boys, hey, Nell.
0:58 Speaker 02 Hey, there.
0:58 Regina Barber? So there is a way that the Inca Empire is unique.
1:02 Speaker 02 Well, maybe there's lots of ways, but we are going to talk about one thing.
1:06 Regina Barber? This intersection of numbers and knots, something I actually learned about last year on top of that, like, famous Inca fortress Machu Picchu.
1:13 Speaker 02 I am so jealous you've been there. I have not. I learned about these knots and numbers when I was talking to a researcher named Kit Lee. She's affiliated with the University of St. Andrews in Scotland.
1:25 Speaker 03 When you're learning about empires in school, oftentimes the way they teach them is that every empire, big civilization, has writing. So the Inca Empire is almost always called out as an exception to this. Oh, they're such a big empire. They covered half the continent, but they don't have writing. How could that be?
1:42 Speaker 02 She says what's often overlooked is that they did have this elaborate system of record keeping, you know, all kinds of records that involved making knots in chords.
1:53 Regina Barber? Yeah, knots in these chords. It's amazing to think that this huge empire kept all these records. And I remember seeing this recreation of one, and there were like colors in the chords. They were really, really beautiful, and those colors were important, too.
2:07 Speaker 02 Right, yeah. I mean, the colors contained meaning, the position of the knots along the chord, the type of knot, the numbers of chords. Like, everything was a kind of code. And literacy in this form of writing or record keeping.
2:23 Speaker 02 Was assumed to be this kind of rare esoteric thing that only the highest levels of Inca society could do, you know, kind of this elite practice by men in the ruling class. But, you know, what Kit and a colleague recently told me is that they came across this one set of really unusual knotted strings that has called all of that into question.
2:47 Regina Barber? Oh, I love where this is going. Today on the show, why anthropologists may have been wrong about which members of the Inca empire made these ancient records, and what that means for understanding how these knots are related to objects that some people still make today. You're listening to Short Wave, the science podcast from NPR.
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4:38 Regina Barber? Okay, now, let's just help people visualize what these Inca knot records look like. I'm sitting here, I'm looking at this picture you sent me from the Smithsonian, and we've got this like, long chord, sort of horizontal in the photo, and then hanging down vertically from that horizontal chord are these other chords with knots in them.
4:56 Speaker 02 Yeah, so, there's the so-called main chord, the horizontal one, and then the ones hanging down from it are called pendant chords. And the whole thing, the whole record, is called a quipu. The word comes from a part of the Inca language that means knot. And everything has meaning in this thing. The placement of the knots along the strings, the order of the strings, their color, everything is thought to be kind of a record, of something that somebody could look at and make and read to look at, you know, a census, or crop records, or whatever they wanted to be counting and keeping track of.
5:32 Regina Barber? And what we're looking at right now is like, half a millennia old. Like, can people still read this today?
5:39 Speaker 02 It's hard. I mean, some quipus are thought to contain numerical information. So they can sort of tell that the knots are arranged in a decimal system, with like, a place for tens, a place for hundreds. I mean, there's lots of things you would want to count like that, right?
5:52 Regina Barber? That makes a lot of sense, that decimal system, to me.
5:54 Speaker 02 But the thing is, there aren't really a lot of quipus still in existence from the Inca Empire. I mean, they were made of cotton, so a lot just kind of degraded in the environment.
6:03 Regina Barber? Yeah.
6:04 Speaker 02 And then the Spanish colonizers actually destroyed and burned a lot of them.
6:07 Regina Barber? Oh, geez.
6:08 Speaker 02 So, in museums and universities worldwide, there's only about 1,000 quipus still in existence.
6:14 Regina Barber? Ooh.
6:14 Speaker 02 And there's often no information about where they originally came from.
6:18 Regina Barber? Yeah, I can see how that would make it very hard to like, learn more about them to be able to read these records.
6:24 Speaker 02 I was talking to Harvard University quipu researcher Manny Madrano, and I asked him, like, to what extent can people today read quipus?
6:32 Speaker 05 Well, it depends which khipus we're talking about, right? Because of an Inca khipu that came out of a grave, for example, you know, from the 1400s, I'm not aware of any modern reading, let's call it, of an object of that age that is universally agreed upon.
6:46 Speaker 02 But then you've got khipus that have been made by communities in the Andes in more recent times. You know, there is this tradition of kind of symbolic nodding.
6:54 Regina Barber? So you could just ask them, right?
6:57 Speaker 02 And researchers do. I mean, Kit Lee told me, you know, some are related to agriculture, like keeping track of herds.
7:03 Speaker 03 But you also have during COVID, you had a resurgence of funerary khipus, which are more of a cultural religious signifier as well. So both of them are happening.
7:14 Speaker 02 Like, people are buried with a sort of long khipu string tied around their waist. But Lee told me it's been thought that these modern practices weren't really related to the more ancient khipu records from the Inca Empire.
7:26 Regina Barber? Yeah, why do they assume that?
7:28 Speaker 02 Well, for one thing, the modern khipus just look different, like they have a different shape. And then there's the people who make them.
7:35 Speaker 03 And modern khipus tend to be made by lower status people. So hacienda workers, peasant laborers, herders.
7:43 Speaker 02 And like I said before, you know, records from the colonizers said that khipus in the Inca Empire were made by elite men. So, you know, this high-level bureaucracy at the top levels of the ruling class of this empire.
7:55 Regina Barber? Yeah, and you said that this may be called into doubt with like this one set of knotted strings, right?
8:02 Speaker 02 Exactly. So it's a khipu acquired by the University of St. Andrews. And Sabina Highland works there. She told me she initially thought this thing was a modern khipu. But then she did scientific dating, and it showed that this khipu was about 500 years old.
8:20 Speaker 06 Which astonished me. That was the first surprise. Then Kit, I was showing it to Kit, and this was the second surprise. Kit looked at me and said, Sabina, this primary cord is human hair.
8:32 Regina Barber? I love her enthusiasm, but like, human hair, how is that the key here?
8:38 Speaker 02 Well, you know, they had thought like, okay, maybe it's animal hair. But when Kit was looking at it, she's like, no, it's too long and glossy to be, you know, animal hair, like from a llama or something. I mean, this is a long, dark brown cord made of long, human hairs, like three feet long. So it's like years of hair growth.
8:57 Speaker 06 What it is, is a person cut off a hank of their hair. And then they doubled it over and twisted it.
9:04 Speaker 02 The reason this is important is that she knew of some historical information suggesting that herders and others would sometimes tie human hair to a quipu as a kind of signature, right?
9:15 Regina Barber? Okay.
9:16 Speaker 02 So she thought, maybe this hair came from the person who made this quipu.
9:20 Regina Barber? But, but there's no way to know for sure that it was the person who made it?
9:24 Speaker 02 No, you don't know for sure, but she knew that in the Inca Empire, hair had a lot of meaning.
9:29 Regina Barber? Hmm, okay.
9:30 Speaker 02 As a sort of personal signifier, like the emperor's hair clippings were saved during his lifetime and worshipped just as he was, you know?
9:37 Regina Barber? Oh, okay.
9:38 Speaker 02 And so she thought, here I have this hair that could be from the maker of this quipu, and she realized she could do a chemical analysis of the elements, like carbon and nitrogen, in this hair to get clues about what kind of food this person ate. This is a kind of analysis that's been done a lot in the past on like, things like mummies.
9:57 Regina Barber? This is so fascinating, I love it. What did she find?
10:00 Speaker 02 Well, she says it didn't look like a rich person's diet.
10:03 Regina Barber? Wow.
10:03 Speaker 06 This person who personally made this quipu had the diet of a commoner.
10:09 Speaker 02 So not a lot of meat, and not beer made from maize, which was the popular ritual drink of the ruling class.
10:15 Regina Barber? Okay.
10:16 Speaker 02 And I asked her, I was like, look, maybe this person was just a vegetarian, you know? And she was like, sure, you could theoretically avoid meat.
10:23 Speaker 06 But maize beer is different because these very high-ranking elite quipu officials, as part of the process of getting record-keeping, they were involved in rituals in which it was mandatory to drink a lot of maize beer.
10:42 Speaker 02 She just doesn't think that was avoidable if you were in the ruling class.
10:46 Regina Barber? So then this means that this person must have not been, right, an exalted person? They might have been a commoner, right?
10:53 Speaker 02 I mean, that's the idea, and if that's true, then maybe the Spanish colonizers got it wrong when they wrote these accounts of what they thought was going on in the Inca Empire.
11:02 Regina Barber? Very possible.
11:03 Speaker 02 I mean, maybe literacy in quipu-making and reading was more widespread. And Kit Lee told me that, you know, the Inca Empire and the quipus have really been mythologized to a certain extent.
11:16 Speaker 03 There's this idea of it being a glorious past of the Andes, that it's a bygone day, you know, because the Spanish destroyed it. Colonia doesn't destroy it.
11:23 Speaker 02 And, you know, if it was destroyed, then there's this assumption that, of course, these not records that people make today are just this kind of like degraded form of what used to be this like glorious past. Sabina Hyland told me.
11:35 Speaker 06 Everyone knew, right? The quipus were only made by high status elites who were wiped out by the Spanish. So quipu use stops. And anything modern people do is just almost like a triviality.
11:47 Regina Barber? I assume she doesn't feel that way at all.
11:50 Speaker 02 Not at all, not at all. Like, last year, she was invited to this community called Hakul. It's this remote village in the Andes.
11:58 Speaker 06 That has quipus. They asked me to look at it. They'd never shown their quipus to outsiders before.
12:04 Speaker 02 And for one thing, these ancestral quipus she saw had human hair tied to them, which the people told her was like a signature of the maker.
12:13 Regina Barber? Oh, this is fascinating.
12:15 Speaker 02 Yeah, and these quipus also had a lot of tassels on them. And she told me that ancient Inca quipus can have tassels on them, too. And so she's hoping to go back next year and learn more about the tassels and like what kind of meaning they have by just, you know, talking to people there.
12:30 Regina Barber? I know, talking to people, it's a radical notion.
12:32 Speaker 02 Very old school. It's not like using AI. It's just talking with people.
12:39 Regina Barber? Nell, thank you so much for bringing us this story.
12:41 Speaker 02 Oh, it's my pleasure.
12:43 Regina Barber? This episode was produced by Rachel Carlson and lightly edited by our showrunner, Rebecca Ramirez. Tyler Jones and Nell checked the facts. Maggie Luthar was the audio engineer. Beth Donovan is our senior director and Colin Campbell is our senior vice president of podcasting strategy. I'm Regina Barber. Thank you for listening to Short Wave from NPR.
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