Video: Teotihuacan and the Making of a World City


In the first century CE, Teotihuacan became the capital of the area known today as Central Mexico. The city grew to include 100,000 people, drawing immigrants from Western Mexico, the Valley of Oaxaca, Veracruz, and the Maya region. Deborah Nichols will discuss how Teotihuacan became the largest and most influential city in Mexico and Central America; how it maintained this position for 500 years through diplomacy, pilgrimages, military incursions, and commerce; why modern scholars consider it a “world city”; and what challenges exist in advancing an understanding of its legacy.

2018 Gordon R. Willey Lecture and Reception Recorded 3/29/18
Presented by Peabody Museum of Archaeology & Ethnology.

Deborah L. Nichols

William J. Bryant 1925 Professor of Anthropology; Chair, Latin America, Latino, and Caribbean Studies, Department of Anthropology, Dartmouth College


Teotihuacan and the Making of a World City

[00:00:06.33] Our speaker tonight needs no introduction to anyone working in archeology in the United States or Latin America, because Professor Deborah Nichols is both a very distinguished researcher in her own field, but also an exceedingly conscientious and insightful member of both the Society of American Archeology, for which she serves as Treasurer after a series of other posts over the past couple of decades.

[00:00:32.78] But also on the Archeology Committee of the American Anthropological Association, where she has been an elected member of the executive board and Chair of the Archeology Division, among other roles. She is or has been on the advisory and editorial boards of virtually all the most prominent archeology journals and several in anthropology, published in the US and Mexico.

[00:01:00.34] At Dartmouth, Professor Nichols-- Deb, to our who are legioned, and whom I consider myself proud to be one, along with Barbara-- serves as the William J. Bryant 1925 Professor of Anthropology and Chair of Latin America, Latino, and Caribbean Studies.

[00:01:21.77] She's held just about any post a good citizen at that fine institution could hold. I see John smiling over there. She's a popular teacher, a great colleague, and friend to all, both in and outside of Dartmouth, and a terrific advocate for archeology, for anthropology, for international studies.

[00:01:42.84] Professor Nichols obtained her PhD at the Pennsylvania State University, with the late, great, Harvard-trained William Sanders, who gave the inaugural Gordon R. Willey lecture. Sanders deeply appreciated Deb's work on the central question of his own dissertation, water management and its role in the evolution of civilization in the Basin of Mexico, among other topics.

[00:02:06.96] She then directed excavations at the Black Mesa Archaeological Project in Arizona, from 1980 to '85, which led to her first two books, before taking up shop at Dartmouth in 1985, where they know they are lucky to have her and her extraordinary ethnographer husband, John Watanabe, who studied the living Maya here at Harvard with another late and great scholar, Professor Evan Vogt.

[00:02:34.41] Their son, Aaron, is also with us, and there must be something in the water around these parts, because Aaron got his BA at the college and is now back for more punishment, getting a PhD in Government under Professor Steven Levitsky. It's great that you're both here.

[00:02:52.62] So it would take the next half hour, which none of us want to do to, list all of Professor Nichols's NSF and NEH and other grants, awards, fellowships, symposia, and invited sessions, articles-- 60-some odd of them on academia alone-- books, field projects, including some really important ongoing work at a site called Altica, online databases, contributions to institutions, and prizes, including the Gordon R. Willey prize of the AAA, editorial boards, classes-- man, I'm getting worn out just reading this list. I don't know how you do all that.

[00:03:34.80] So instead, I'll just read a few of her more recent book titles to give you a sense of the depth and breadth of her scholarship that relates to this evenings Gordon Willey lecture. Most recently, the book, Rethinking the Aztec Economy, with Francis Berdan and Michael Smith.

[00:03:53.28] She's coauthored so many articles and books, and those of you who've done it know that that's a lot more work than just writing the darn thing yourself. So that's a real tribute to Deb as well.

[00:04:03.39] The Oxford Handbook of the Aztecs, the Oxford Handbook of Mesoamerican Archeology, Multidisciplinary Approaches to Social Violence in the Prehispanic Southwest, with Patty Crown. Archeology is Anthropology, how's that for a topic? It was one of Gordon Willey's favorites, actually. And The Archeology of City-States, Cross Cultural Approaches.

[00:04:28.68] So really, it's a wonderful honor to have our pal and great colleague and fabulous researcher, Deborah Nichols, with us tonight. So please join me in welcoming her for this evening's lecture.

[00:04:40.42] [APPLAUSE]

[00:04:51.34] Many thanks to Bill, for a very warm, if not too effusive, introduction that I probably won't be able to live up to. And to many of you, who've come today to talk about one of the places that, for me, it's probably hard to get me to stop talking about it, Teotihuacan.

[00:05:07.03] And actually, it was the first archaeological site I ever saw in Mexico. And I'm going to try to talk a little bit today to put it and the research there in a broader context for you, because Bill asked me to speak on the topic of directions of research at Teotihuacan.

[00:05:22.96] And when he asked me, it was about the same time I was asked to write what's called a memorial for Rene Million, a central figure in Teotihuacan archeology for the National Academy of Sciences, to honor on his passing, his many contributions. And it got me thinking about what we knew, how we came to know Teotihuacan as we do today, and then the directions for where research is going.

[00:05:45.07] So I'll try to put those things in context for you. And let me begin here, by making a couple of observations that, one of which that urbanization, the process of people moving and creating cities, is probably one of the most important social transformations that have taken place in human history.

[00:06:02.57] It's one that we are still in the midst of, as you can see in this graph. The 21st century represents the first time in world history that the majority of the world's populations lived in a city. And yet, this transformation, and it's clearly a historical one, began in a limited number of places in the world, in the Ancient World.

[00:06:23.73] And central Mexico, the area where Mexico City is today, the large geographic basin that it sits in, was one of these core areas for the founding and the development of the earliest cities. And that's what we're going to be taking a look at today.

[00:06:37.34] But giving you some larger context here, but many people are perhaps not aware of, in that Teotihuacan wasn't even the earliest of the cities, there was one slightly earlier one in this region. But it really began an urban tradition that has persisted for 2,000 years, because this part of the world has been one of the most urbanized places in the world for over two millennia.

[00:07:03.52] That itself is a striking fact, particularly when we think of it in the broader terms that Harvard's economist Edward Glaser has done. And who looks at it as cities as one of the great human inventions. And he certainly looks at it from the bright side.

[00:07:18.80] So these have some little bit of downsides occasionally to them. You'll notice a little bit of air pollution in the slide on Mexico City. But nonetheless, these were enormous-- for each, in their day-- enormous urban concentrations. How did people make them work? How did they come into being? And what are the implications of this?

[00:07:35.80] Particularly striking in the case of Teotihuacan is the fact that at the time the city began to form and grow in size, in the beginning of the Common Era, it had basically been a pretty marginal place of small agricultural villages. And here, I'm looking actually, off to the one edge of the ancient city, looking down, and you can see the pyramids out in the distance.

[00:07:57.50] So how did that transformation happen? How did this countryside become one of the most urbanized places in the world? And in thinking about that, one thing to bear in mind is that Teotihuacan is not a place that was ever completely lost to history.

[00:08:12.13] Its pyramids were so massive that they have persisted into the modern era. And it is with some good fortune that this part of Mexico has been made relatively more rural, that has given us access to this city as archaeologists in the way that is not the case, for example, at the great city of the Aztecs, which underlies most of Mexico City. And

[00:08:31.57] I encourage those of you have the opportunity to hear Eduardo Matos Moctezuma to come back for his-- what I'm sure will be a fabulous talk on the great temple of the Aztecs. So at the time that the Aztecs began to form their empire in the 1400s, Teotihuacan was still an important place historically, and important place ritually.

[00:08:51.25] The ruler of the Aztecs, Montezuma, made pilgrimages there. They saw this as the place where history had been created, in which the fifth world in which they lived, where the gods had sacrificed themselves to make time to launch the universe. And here, these are representations from colonial period maps, where they believed at the great-- what we now call the Pyramid of the Sun, and the Pyramids of the Moon is where a great Oracle resided.

[00:09:17.53] So this place has played an important role in also providing the historical validation for later cities and later states in Mexico. I've called it a world city, in the sense that there are a handful of ancient cities who had unusually outside influence in their parts of the world.

[00:09:35.74] You can think to Rome, is one, Constantinople is another, where they were important political capitals, but whose influence extended well beyond their political boundaries, and whose influence also persisted in time, because Teotihuacan continues to have an important role in the conceptualization of the modern nation-state of Mexico, and its conceptualizations of its history.

[00:09:59.59] But going back, during the Spanish colonial era, the pyramids of places like Teotihuacan did not-- they were not of great interest to Spanish colonizers. Well, were a place for which antiquities were dug up and things of curiosity, but by and large, they didn't receive much investigation, because that might have raised some questions, of course, about the validity of the Spanish conquest.

[00:10:22.45] But as Mexico established itself as a modern nation-state, Leopoldo Batres-- and Bill Fash has written on this quite eloquently-- turned his attention to these pyramids as part of the way of validating the modern Mexican state, creating a kind of, as Bill has used the term, archeology of state in looking at past states.

[00:10:43.90] And his excavations, whether he correctly reconstructed the Pyramid of the Sun or not, it did put Teotihuacan and this great edifice within the historical consciousness of Mexico. And this really begins to launch an era of investigations where archeology becomes and has a role in the politics of the state, that it doesn't really carry here in the United States as it does in Mexico.

[00:11:13.87] Another young Mexican, Manuel Gamio, who had been educated early, in one of the earliest departments of anthropology at Columbia University, begins to do excavations following something that we all take for granted today, and that's excavating according to layers and stratigraphy, because at this time, they really only believe that there had been two great civilizations in ancient Mexico, the Toltec and the Aztecs.

[00:11:39.87] And actually, many people believed that since they were aware that Teotihuacan was older than the Aztecs, it must have been the capital of the Toltecs. Through stratigraphic excavation, this is before anybody had radiocarbon dating, they looked to try to figure out where to create a kind of history of the past without having written text.

[00:12:00.78] And here he did it using layers in the soil. And also importantly, changes in ceramics. So another point that I'm going to make today is that while Harvard and the Peabody Museum is certainly well known for its importance in Mesoamerican archeology, today it's most often associated with the great work that has been done in the Maya region.

[00:12:22.49] Of course, that's where Gordon Willey carried out his own career. But Harvard and Harvard-trained archaeologists were also, and have been and continue to be, very important in the work at Teotihuacan.

[00:12:34.17] And I'm going to touch on some of those bases today, beginning here with Tozzer, who is, again, one of the leading early archaeologists here. He did work outside of Mexico City. He excavated a mound called Coyotlatelco, in an area near where Gamio had excavated, and identified this style of decoration of pottery that we now know dates to the time just after the collapse of Teotihuacan.

[00:12:58.20] Another Harvard-trained archaeologist, George Valliant, excavated villages north of Mexico City where he defined the period that preceded Teotihuacan and the establishment of the earliest villages. And this is one of his excavations there.

[00:13:13.23] Manuel Gamio goes to Teotihuacan to launch what would really become a signal project that helped found anthropology as a discipline in Mexico. And he began it doing archaic magical excavations, here at the Pyramid of the Feathered Serpent. And we'll see some more images of it, so you come aware of why it gets the name the Feathered Serpent. But he is actually the one who first identified these fabulous sculptures.

[00:13:38.92] This is a period that, again, they're further laying out, they're putting where Teotihuacan fits in time. Of course, today, we have chronologies that look like this, but Ignacio Bernal, one of the great figures of Mexican archeology, who's written about this history, talks about the period from 1910 to 1950. And he calls it the period of when potsherds, broken pieces of pottery were victorious.

[00:14:04.86] Because this was the period of time they used changes in style of pottery and stratigraphy to put Teotihuacan in time. Now, having begun to get a sense that Teotihuacan was older, and much older than the Aztec world, but how old, that it dated after the founding of the earliest farming villages.

[00:14:24.87] But a lot of Mexican archeology was very focused on pyramids and monumental architecture. And Teotihuacan con was not seen as a city in 1940. If you look at books even into 1950-- if you look at books written about the Ancient World into the 1970s, there are virtually no places in the Americas that are presented and included as those as cities of the Ancient World.

[00:14:49.86] They were seen as ceremonial precincts because they conceived of the ancient polities and states of the Americas as theocracies, as led by priests. And therefore, these priests had these places where they conducted their rituals and those formed the political capitols.

[00:15:08.43] But a whole series of events, including the Depression, World War II, the Spanish Civil War, the aftermath of World War II, and ultimately, the Cold War, would come to kind of help to reconfigure and spur the growth of the social sciences in the Americas, and lead a whole new generation of people from very different backgrounds to come to be interested in the archeology of Teotihuacan.

[00:15:35.43] And I'm going to mention some of those. So the first of these is Pedro Armillas. He was Spaniard, he participated and he fought in the Civil War, fled to Mexico after the Civil War, but was very influenced by readings on a book, and several books by V. Gordon Childe, who coined this term the urban revolution.

[00:15:55.68] The recognition that there was a period of time in human history where there were no cities. And cities came into being, and that this was one of the great transformations. And that archeology could contribute to understanding these historical developments.

[00:16:08.52] This is a slide of him. I've discovered that in the age prior to cell phones, it is much more difficult to find photographs of many people than today, where there is all of them on Facebook. But finding of, actually, photographs of many of my older senior colleagues has proved a little more challenging.

[00:16:27.39] This is one with Pedro Armillas from 1967. It's up in the hills above where Mexico City is located. But Armillas comes to Teotihuacan and, having read Childe's book, he begins to think about these pyramids in a different way.

[00:16:43.62] He undertakes and is involved with excavations at some of its big residential areas in the city. And he recognizes, and he is the first archaeologist to actually recognize Teotihuacan as a city. He actually takes a lot of Mexican archeology to task for an overwhelming preoccupation with pyramids, with aesthetics, and he tries to bring archeology into a larger social science and comparative perspective.

[00:17:11.64] He is a very charismatic individual. I had the opportunity early in my life to have met him. I can understand, when you did-- I was with Bill Sanders-- that you just listened to him talk for two hours. And he was full of ideas and great thinking.

[00:17:25.98] And what happens on the heels of World War II, and one of the great social reformations that came out of World War II in the United States was the GI Bill. The GI Bill had a significant democratizing effect on US higher education, particularly, at least for, Euro-American men, who were able to attend universities like Harvard and Columbia, who had come out of working class, in many cases, immigrant family backgrounds.

[00:17:58.62] And I'm going to introduce some of those cast of characters, because they come a role in the making of the city. One of them was René Millon. His father was born in France. He was a photographer, and a very early aerial photographer, here in the United States.

[00:18:13.41] René was interested in history, wasn't sure what he wanted to do with his life, but was able to go to Colombia on the GI Bill, was fascinated with China. And finally, he goes to the University of Michigan after he gets his undergraduate degree, takes some anthropology courses, including some by one of the great figures, Leslie White.

[00:18:32.49] And this draws him, he thinks, anthropology, this is a really interesting discipline. They're new, they're not set in their ways, I can think creatively. They'll let me do things comparatively. And he begins to think archeology is a way to do comparative history.

[00:18:45.03] Well, he can't work in China. This is the media post-World War II era. And Gordon Willey offers him data from the Viru Valley Project for a Master's thesis at Columbia. And having written his Master's thesis, Willey suggests to him that he actually go to Mexico and he meet this young Spanish archaeologist who's full of ideas, Pedro Armillas.

[00:19:06.06] So it's the 1950s-- early 1950s. Million had served in the Pacific during World War II. He doesn't particularly want to get drafted again for the Korean War. So he and a bunch of other graduate students from Columbia get in a car and they drive to Mexico City.

[00:19:24.12] He goes with Pedro Armillas to Teotihuacan. Armillas shows him around, and to use René's words, "That was it. I was hooked. I knew where I was basically going to spend the rest of my life." And that was the case.

[00:19:36.45] At the same time, a son of an Irish immigrant who grew up on Long Island, who read a book by another famous Harvard historian, William Prescott, who wrote books about the conquest of the Aztecs and the conquest of Peru. Bill Sanders had read these.

[00:19:52.83] As a kid, he was fascinated. That actually began his interest and the Aztecs. So when he came to Harvard, he knew exactly where he wanted to go and where he wanted to study, and that was over here to the Tozzer Library.

[00:20:05.97] And at this time, Gordon Willey-- who's in this lecture-- had done work in Peru that proved to be path-breaking for archeology, because it established a new method in the field of what we call settlement pattern survey, of actually looking at the distribution of archaeological sites over the landscape.

[00:20:26.36] Willey introduced Sanders to this idea, who was also getting ideas. The GI Bill allowed them actually to take courses in Mexico at the School of Anthropology. So there, he met Pedro Armillas, there he met René Millon. There he met another important figure, Eric Wolf.

[00:20:42.99] And he began to see Teotihuacan as a place where you can take Willey's idea of settlement patterns and use it to think about creating a history of the development of these ancient cities by looking at changes in settlement over time. And what happens next in this 1950s, is he writes a paper for a volume that Gordon Willey put together from a conference on settlement patterns in the Americas.

[00:21:11.84] And Sanders begins to lay out his idea of conceiving thinking about approaching cities, not just looking at their buildings, but putting them in a much larger regional context. While he's doing that, Millon is running around Teotihuacan.

[00:21:28.19] And among a couple of things that he did, is he and another archaeologist teamed up, and they decided to do a survey in the area just what is now to the north and west of the Pyramid of the Moon. And they discover that there's more mounds, that this place is much bigger than anybody thought. They also go on and do some work with another archaeologist. Millon persuades the National Institute of Mexico to let him go back in and look at a tunnel that had been dug in the Pyramid of the Sun.

[00:22:01.40] And they do this, and they look at the stratigraphy. And they realized this Great Pyramid was built very early in the history of the city. Now this is a time when most of my students at Dartmouth, when they come in to take a class, look at these pyramids and they have visions of slaves. All right, of people being enslaved to build these massive, monumental pyramids.

[00:22:20.99] And Millon quite astutely thinks this is built really early in this city's history. These people must have built it, in part because they believed that what they were doing was building something good. And he had a very different conceptualization for what these pyramids might have meant and the meaning that they had for people.

[00:22:41.51] In 1960, Eric Wolf, who was now a young faculty member of Columbia University, convened at the University of Chicago, a conference on the future of archeology in the Basin in Mexico, the area around Mexico City. Teotihuacan was the place they thought that they should begin their investigation of this whole series of ancient cities, this ancient urbanism. There's Eric's book.

[00:23:05.34] And so in that conference, it was decided that René Millon would try to make the first comprehensive map of Teotihuacan, that Bill Sanders would try to conduct the first regional settlement pattern survey of the Teotihuacan Valley.

[00:23:20.72] As all this was getting underway in 1960, and 1961, and '62, the Mexican government initiated another major special project at Teotihuacan, led by two of Mexico's most prominent archaeologist Ignacio Bernal, seen here, and Jorge Acosta.

[00:23:38.36] They excavated along the main avenue of Teotihuacan, reconstructed facades of public buildings. Acosta the excavated this building, for example. What's commonly in English referred to as the Butterfly Palace, which we now know has all kinds of military emblems and insignias associated with it.

[00:23:58.61] But Acosta was also the first person to argue the Teotihuacan was not the capital city of the Toltecs. That the capital city of the Toltecs, in fact, was the city of Tula, located well to the north. Although, conceptually, Teotihuacan may have been seen as a conceptual early beginning of civilization.

[00:24:19.58] So you have this massive project going on that begins to put Teotihuacan in the face, for those of you who have been there, that it takes today, as Millon and his crew, sets out to map this city. Now René Millon's father was an early aerial photographer. And from that, Millon used what he learned from his father to use aerial photography to actually map the city with.

[00:24:43.49] They used aerial photography also as a base on which to walk the entire area, try to figure out the boundaries of the city, and collect examples of artifacts from the surface everywhere they found concentrations of artifacts or remains of mounded architecture. It was an enormous undertaking. There had never been such a comprehensive map of an ancient city ever attempted on this scale so far.

[00:25:11.34] And as Millon himself with later go one to say, had I known how big an undertaking it would, I never would have done it. It really preoccupied his life for the next several decades. He recognized that he was going to need some help with this project.

[00:25:28.88] And both brought in a generation of younger archaeologists to work on various stages of the project, but also another important figure who had gotten his education at Harvard, George Cowgill.

[00:25:42.05] George Cowgill had followed in good Harvard tradition, going into Maya archeology, but he had been a physics major as an undergraduate student, coming off of an Idaho farm. And he had this quantitative background, just as computers were coming to play in a bigger role in archeology, allowing us to computerize massive data sets to apply quantitative analyzes.

[00:26:07.34] Millon's survey had collected a million pieces of pottery. They started in a place called "The Lab,", which we still refer to the place where it's stored as The Lab, but now it is a two-story high building containing all of these collections. And Millon knew that he was in over his head in terms of being able to analyze this massive amount of data.

[00:26:28.43] And so he sought the help of George Cowgill, who became the other the part of this team that led to the publication of the map in the early 1970s. Now this map is important and several important features that came to light in their course of doing these collections and making the survey.

[00:26:45.58] One of which was to discover this entire city was oriented to a single grid plan, into a single astronomical orientation that lies 15 degrees, 30 minutes east of astronomical north. The original old city was-- let's see if I can find a pointer here-- was up in the very northwestern corner. And we'll figure out how to turn it on.

[00:27:11.14] OK, over in here, and that soon as the city began to grow, its rulers audaciously laid out this central avenue. And they began the construction of massive monumental architecture. Virtually every river, smaller streams, and buildings were all eventually built to conform to this grid plan.

[00:27:33.94] And this kind of orthogonal grid plan is actually relatively rare in ancient cities. But it's one of the reasons why, when people go to visit, they see and recognize Teotihuacan is a city, because don't cities have orthogonal grid plans? Well, it turns out, actually, 2,000 years ago, no. In fact, most of them didn't

[00:27:51.38] Boston still doesn't.

[00:27:52.68] And that's right, and some cities are still trying to use cows paths as its arteries for transportation. So he recognizes this, recognizes that this must have had some significant organizational implications about the ability of Teotihuacan rulers to undertake this. That it must have some ideological, it must have had some meaning for them, in terms of how they oriented the city.

[00:28:17.32] And so for Millon, this told him that religion was playing an important role in early cities. He also recognized another early feature. There were all these little squares on this map. These little squares each represent an apartment compound, a multifamily one-story dwelling.

[00:28:36.73] They vary in size and degree of elaborateness of architecture, and yet they follow a similar architectural canon. And there are 2,000 of these in this city. So you have a standardized architectural form that had never existed before in Mesoamerica.

[00:28:52.29] The city is reorganized with this architectural form. And here is little layout of the city street, along the Street of the Dead, as we call it today, standing here at the Pyramid of the Moon. There's the Sun Pyramid, with, of course, people standing on it, because it's still an icon of Mexico. And here's the interior courtyard, where you have one of these smaller versions of a temple.

[00:29:14.56] So that these apartment compounds he recognized were the important social group in Teotihuacan. There were individual families. The families who lived in an apartment compound shared similar occupations, they often shared some more ethnic and class orientations, they were integrated with one another through ties of kinship and marriage as well.

[00:29:34.99] And I'll point out another feature which will come important about Teotihuacan, is that it has a distinctive style of architecture that it didn't create, but it used it over and over again, repetitively. So this style of architecture became a signature of the city.

[00:29:50.59] And abundant uses of white plaster, in an area where there is no limestone to make white plaster. So that's an interesting thing in itself, where it got this from.

[00:30:00.28] So Millon creates this comprehensive map. We understand the apartment compound is fundamental as an architectural and social unit in the city. At the same time, Sanders is doing the archaeological survey.

[00:30:12.28] Sanders's vision was to survey the Teotihuacan Valley, systematically, walk over most-- they cheated-- they didn't really cover the whole entire valley, but they covered 600 square kilometers of it-- to map all traces of archaeological remains of all time periods that they could find, up to the period of the Spanish conquest.

[00:30:31.93] He envisioned this to be the first in a series of surveys that eventually would cover the entire Basin of Mexico. When they began the surveys, much like Millon had the daunting task of figuring out how to map this big city, they had the daunting task of figuring out how to actually implement pedestrian survey on a large scale.

[00:30:51.91] Again, today we take for granted that you can just turn to Google Earth and get an aerial photographic view of the landscape. That was not the case in 1960. There were small-scale aerial photographs that were available.

[00:31:04.72] And Jeffrey Parsons had been an undergraduate student of Bill Sanders at Penn State. Bill sent him on to Michigan to work on his PhD, but Parsons had worked with a geologist one summer. And this geologist used aerial photographs for orienteering and mapping geological features.

[00:31:21.88] And he said, we could use aerial photographs to do the same thing as mapping archaeological sites. Willey had used aerial photographs, but in a slightly different way, when he had done his work in Peru.

[00:31:32.65] Well, just to give you some sense of the changes in technology, in order to get an aerial photograph large enough that you could map features onto while doing field survey, they had to figure out a way to enlarge the photographs, because when you bought them, they were only about this big.

[00:31:48.71] So they bought a photographic enlarger. And one of the graduate students, they put a bed on a chair in a room, in the town of Teotihuacan. And they stood up on the chair. And then this graduate student, with others holding on to him, took his camera and made other photographs that they enlarged of the aerial photographs to take out into the field, typically on a piece of board like this.

[00:32:11.23] This all seems almost, by today, 50 years later, pretty crude technology, but this was cutting edge at the time. And as Parsons writes, there were only about a handful of archaeologists anywhere in the world who were using aerial photography in the way they were doing it and the way Millon had done it.

[00:32:28.36] What this mapping-- and they did this in the 1960s. They would go on to do the rest of the surveys of the Basin of Mexico over a period of about 15 years, with Sanders completing the final stage of it in the mid-1970s. And what they discovered was one of the most dramatic changes in regional settlement patterns of any time, anywhere in Mesoamerica.

[00:32:53.69] If you look at these maps, and the size of the circles roughly kind of represent the size of different archaeological sites. So as Teotihuacan is beginning to grow here, there's another major city in the southwestern corner of the basin named Cuicuilco. And there are a lot of smaller capitals of local regional polities.

[00:33:15.19] You turn the clock, and as Teotihuacan explodes in the first century of the Common Era, you notice that there are hardly any sites. 85% of the people in this region of some thousands of square kilometers are all living in the city of Teotihuacan.

[00:33:36.20] There's another-- I don't know-- 5% or so clustered around here. And then a small group distributed down here. Eventually, the city of Cuicuilco itself will be completely abandoned. So it had acted like a giant vacuum, pulling people into the city.

[00:33:51.87] And at a really extraordinary change, and you couldn't have known this if you hadn't surveyed the whole region. Because when I was first exposed to archeology in Mexico, I worked on the last stages of this survey as a graduate student-- well, now everybody can figure out how old I am.

[00:34:09.91] And Bill was still wrestling with the fact of were we going to find sites of this time period over in the northern part of the basin? And we didn't. But soon after, everybody is pulled into the city of Teotihuacan, you begin to see Teotihuacan imitation sites out in the countryside.

[00:34:28.21] So back to our Teotihuacan map here. So by the 1970s, we have now gone through this period of time where we've gone from Teotihuacan as a ceremonial center to Teotihuacan as a city. And conceptualizing future investigations on the basis of seeing it as a city.

[00:34:48.28] There was one other key player in this. Or two, really, others. First the Institute of Anthropology and History that has an archaeological council in Mexico, over this period of time, grows. They become responsible for major archaeological sites and the care and protection of them.

[00:35:05.74] But they're also going through a professionalization of the training of archeology, how you do archeology, and beginning to create their first generation of doctoral students coming out of the National University in Mexico.

[00:35:19.87] And one of the earliest students was a woman, one of my contemporaries, Linda Manzanilla, who would take courses when Bill Sanders was in Mexico. So the Harvard connection continued to yet another generation in another continent, about the importance of survey, about the importance of excavating residential architecture.

[00:35:40.54] Another important institutional development that had nothing to do with Teotihuacan, but had everything to do with the Cold War, was the National Science Foundation.

[00:35:50.35] The National Science Foundation was created after World War II to spur scientific research in the United States in response to the Cold War with the Soviet Union. And they created a division-- a relatively small division-- for the Social Sciences. And within that, created a small anthropology division.

[00:36:12.64] All of the funding for the Teotihuacan mapping project, the funding for the Basin of Mexico survey project, and for generations of research since, the principal source of it for American archaeologists has come from the National Science Foundation, in the same way that INAH has been the principal support of research at Teotihuacan by Mexican archaeologists, and for Canadian archaeologists, the Canadian Research Council.

[00:36:37.81] These were not institutions that were necessarily created to do inspiring work in an ancient city like Teotihuacan, but we have been very much the beneficiaries of this institutionalized support for research. And for their seeing archeology as having a contribution to scientific understanding in the Americas.

[00:36:57.82] So we have this map. And from the 1970s onward, once this map is published, this becomes a key way for archaeologists to think about their research, to think about where to investigate, and to begin to ask the bigger and deeper questions about how did this city function? How was it first formed? And why did it come to an end?

[00:37:19.33] So I'm going to take you through what I've identified as some of the themes of research that I see being particularly salient now, that come out of the late 20th century. And the late 20th century sees some changes in scholarship within the field of anthropology.

[00:37:38.83] Explanatory frameworks have come to emphasize more about ideas about agency and not just the structure of states leading people to act in certain ways, but how both bottom up and top down work. It's also a period in which Mexican archaeologists has written that we've seen a kind of theoretical and methodological diversification in archeology.

[00:38:02.05] Manuel Gándara refers to it as the time of thematic archeology, household archeology, the archeology of gender, geoarchaeology, you can go down the list. Others have used the term, this is the period of ism's in a lot of social science research.

[00:38:19.51] And you couldn't decide, evolutionism, feminism, you can go down your isms. But we've seen this kind of diversification of theories. And Gandara makes an important point about it, that with regard to places like Teotihuacan, archaeologists have engaged in a kind of theoretical eclecticism. In part, because they're trying to understand a very complex phenomena. And they'll use conceptual frameworks that help them do that.

[00:38:50.54] They move ideas over time, in the same way that our toolkit has expanded. So there's not a simple kind of dominant ideology about how we explain Teotihuacan as there may have been earlier in the 20th century, or mid-20th century or late 20th century.

[00:39:07.82] But there is a way in which this is not just a free-for-all, because one of the other things that I note about this period of theoretical diversification is that the archaeologists who work at Teotihuacan are also very rooted in those archaeological remains. That the ideas that come up with that those remains also drive and guide our ideas.

[00:39:29.83] And this has also been a place that has continued to be one of methodological innovation. That just as René Millon conceived of mapping an entire ancient city, little potsherds on the ground, to not just pyramids, we think about walking over entire landscapes to plot the distribution of archaeological sites and to see how that history was formed.

[00:39:52.09] Now we moved into an era where we're looking at isotopes, and DNA, and very, very tiny things to help us answer, still, what are some very big pictures. So one of the themes that emerges out of the late 20th century, and here, I tagged my colleague Emily McClung de Tapia, is what is the relationship of a big city like this to its environment?

[00:40:14.17] And she conceives of it in a framework that we call historical ecology, to recognize that the landscape that Teotihuacan even grew on had been shaped by the early farmers who live there, just as Teotihuacan would shape that landscape. The late 20th century early 21st century has also seen a great increase in funding about environmental research and particularly in the area of climate science.

[00:40:41.59] So we now have had a number of models done by geophysicists, in some cases, other kinds of climate scientists, that note periods of increased temperature, decreased temperature, greater rainfall, and drought. And our colleagues in geology like to look quickly through their textbooks on archeology and see if they can find a correlation between something in an ancient civilization and their climatic reconstructions. I'm being a little simplistic here, knowing which part of the building that I'm in here.

[00:41:10.21] And in Teotihuacan, what Emily has tried to do is to do this in a much more subtle and nuanced way. To take a look at some of those models and say, well, do I see any evidence of a drought? Either in the plant remains, in pollen remains-- her specialty are plants.

[00:41:28.54] But she took this further and not just looked at the plant remains from the city, but has gone out into the countryside to look at how soil and plants have changed over the long history of the time of Teotihuacan. And here, I'm just giving you a few images here, irrigated maize plant remains, and you can see all the trees. And this is an area near the permanent springs at Teotihuacan.

[00:41:50.20] Here, to this very eroded landscape that we often associate with the effects of Spanish colonialism and the introduction of sheep and massive sheet and gully erosion. So you can't look at the landscape today and think this is what it looked like to Teotihuacanos.

[00:42:04.94] Moreover, their ecological footprint, as we use today's parlance, extends well beyond the Teotihuacan Valley. There were too many people in that city to feed it from the lands immediately around the city. They had to bring in food from other parts of the Basin of Mexico.

[00:42:23.88] And that probably had something to do with why they may have established colonies in places. But it wasn't just food, there were other kinds of resources they needed. All that lime plaster, for example, had to come from an area where there are limestone deposits. You don't get lime any other way. And there are none of those around Teotihuacan.

[00:42:42.51] They went areas to the north, particularly around the Toltec city of Tula. And if you do the calculations of the amount of wood they had to have burned to create that line, probably Teotihuacan's biggest environmental impact came from lime extraction up around the Tula area. And I suspect they left some parts of the Tula area looking like this after a couple of hundred years when they'd removed the trees.

[00:43:07.98] So Emily's work has looked at it in terms of historical ecology. That is an ongoing project. She now has several generations of students. And that's another point I want to make about our understanding of Teotihuacan as a city, is that the research has been multigenerational by teams of people collaborating together and bringing in new generations of students.

[00:43:28.47] I want to turn your attention now to another Harvard trained archaeologist, Evelyn Rattray. The Teotihuacan apartment compounds been a major focus of research. About the social life of the city, about the organizations of its economy, how its own ideology was playing out in households.

[00:43:47.61] One of the observations that René Millon made during the mapping project is that there were parts of this city where there were unusually high concentrations of foreign style pottery. And we refer to these now as ethnic neighborhoods, including one, the Oaxaca Barrio, where people who had originally come from the Southern Highlands of Mexico.

[00:44:07.83] And she went on to investigate both the Oaxaca Barrio. She went on to do important investigations in another that we refer to as the Barrio of the Merchants, where there were merchants from the Gulf Coast who seemed to have married elite Teotihuacan women. The women sort of stayed in charge, they went off on their merchant expeditions.

[00:44:25.89] But you see great concentrations of foreign pottery in this area and what they're trading. Evelyn was also a ceramicist. She loved all those potsherds in Mexico and did key work in reconstructing the chronology of ceramic changes that help us date things. And also investigated and took her work outside of Teotihuacan to other parts of the Basin of Mexico to try to identify where some of the styles and types of pottery came from.

[00:44:55.06] And I'm just giving you a few shots here, that maybe-- this is an older photograph from the Oaxaca Barrio of a tomb. Teotihuacanos and people in central Mexico do not bury their ancestors in tombs like this. But people in the Southern highlands of Mexico do.

[00:45:11.11] And here you have people living in Teotihuacan apartment compounds, but burying their ancestors in Zapotec style tombs, and practicing Zapotec style burial practices, because underneath this bowl were remains of the infant's umbilical cords. Zapotec people placed their children's umbilical cords inside of bowls.

[00:45:30.84] So this neighborhood of people from Oaxaca, we know there were neighborhoods of people from the Gulf Coast, we know there are neighborhoods of people from Western Mexico, Guerrero and Michoacán. We also know, and has only been reaffirmed by very recent work that some Harvard archaeologists are involved in, about the presence of people from the southern Maya region.

[00:45:50.82] So this was a multiethnic city. And it was a city that depended upon immigration as part of its lifeblood. Ongoing from the local region and beyond, Linda Manzanilla has taken up through a series of excavations of apartment compounds to also ask questions about how was the city organized internally.

[00:46:11.25] She's particularly pointed to the role of who she calls intermediate elites. OK, these are not the rulers who were still kind of having trouble finding a Teotihuacan, but elites who organized neighborhoods, who were probably the administrators of neighborhoods within the city, through a long series of excavations.

[00:46:31.81] What has particularly struck me about the work she has done is they probably represent some of the finest household archeology done anywhere. She applies everything from ancient DNA to residue studies on floors to figure out what people were eating, where they were not only throwing their trash, but what they were doing in different rooms.

[00:46:53.97] And to actually connect this up to ties and connections they had to people outside of Teotihuacan. Again, this theme of immigration and ongoing relationships. And she argues that these intermediate elites not only helped administer neighborhoods within the city, but they actually organized long-distance trade.

[00:47:13.29] Within this context of household archeology, here is, again, an example from one of the Teotihuacan apartment compounds. Those are here to give you some familiarity with them. But I also want to show how, in the way ethnicity, how different class differences, these were also expressed by people who lived in a standardized residential unit, and yet also expressed their own individual identities in interesting ways.

[00:47:39.56] So this is an apartment compound that was excavated by one of Bill Sanders's students, Rebecca Storey, for her dissertation work about 30 years ago now. But you'll notice something about this apartment compound. This is an area, it's all been plowed, the big mounts have been leveled by tractor plowing.

[00:47:55.55] But you don't see any white plaster here. And when they started excavating this compound, they were really surprised. And if you look close up here on the bottom, the walls of this compound, many of them were made out of adobe bricks. They have dirt floors. The people who lived here did not have the means to have nicely lined plaster floors.

[00:48:14.72] They were, for a period of time, jewelry makers. They later on became potters. Probably farmed out in this area. But if you look here, at this part of the side, there is a feature that's not typical of Teotihuacan. And that's a shaft tomb burial.

[00:48:30.02] So they created a nice floored pavement. They placed one of their founding ancestors there. And that's something people in west Mexico do. We now know from isotopic studies that some of the people in this apartment compound had their ties to west Mexico.

[00:48:45.28] So this is one end of the social spectrum. Here's another end of the social spectrum. This is from a neighborhood that Rubén Cabrera excavated along the Street of the Dead called La Ventilla. You can see, again, the lovely plastered floors, remains of wall buildings, stairs there, and lo and behold, something else that he found on the floor, glyphs [? of room. ?]

[00:49:04.77] So there have been some big books written about how Teotihuacan didn't have a writing system. And yet, they interacted with people from Oaxaca who had a writing system. They interacted with the Maya who had a writing system. But we had a long book about how Teotihuacan didn't have a writing system.

[00:49:21.90] And then Rubén finds these glyphs on the floor. Now we may still debate about the nature of that writing system, or what language they were writing, that's our favorite thing to debate with each other. But they clearly had some system for writing and recording both history and information in this city.

[00:49:40.26] While there are 2,000 apartment compounds that have been mapped, this was probably not the home of everyone. René Millon noted on the surveys that there were areas where there were concentrations of artifacts that didn't seem to have architecture.

[00:49:53.37] For want of a better word, these are called insubstantial structures. We still don't know them in great detail. But I strongly suspect that this is where probably some of the very poorest people at Teotihuacan might have resided.

[00:50:09.90] The last big theme that I want to point to here has to do with pyramids again, at Teotihuacan. Teotihuacan archeology, beginning in the late 1980s, re-entered a pyramid age. But with a big difference than before.

[00:50:27.90] This was not about excavating pyramids to necessarily celebrate the modern state of Mexico, it was about excavating pyramids to understand the Teotihuacan ideology and to understand its system of government.

[00:50:43.96] We don't have large written texts, as do my colleagues in the Maya region, esteemed rulers or kings. What kind of government did they have? Particularly striking to René Millon and George Cowgill was this pyramid called the Pyramid of the Feathered Serpent. That, on its exterior, had these great carvings of the Feathered Serpent on the outside of this.

[00:51:04.00] And this led them to a hypothesis that perhaps this pyramid was, in fact, a royal burial tomb. And that the early Teotihuacan rulers had been engaged in a cult of rulership, much like we think of the pharaohs in Egypt. And that the Teotihuacanos rejected this, covered over the building.

[00:51:25.35] And maybe this question could be resolved by excavating a tunnel into it. And this is George Cowgill standing on the outside of the tunnel. As they excavated the tunnel, and Saburo Sugiyama led these excavations in the tunnel, they discovered, as they had on the outside, sacrifices of young adult warriors, richly regaled.

[00:51:46.23] They entered and discovered a chamber-- I was actually working in the lab the day they broke into the chamber, and they called Mexico City, and they brought in the engineers. And there was a scene of great to-do. This was going to be the burial chamber, finally answer the question.

[00:52:01.98] And they got in there and they discovered the Teotihuacanos had looted it. They'd gone back into the chamber. So we were left still with a question of had it been a royal burial chamber? Or had the ruler been buried outside? Or maybe this is not where the rulers were buried at all, because they cover over the pyramid.

[00:52:22.27] And this led people to speculate, OK, a big change in governance. But it also launched further excavations of pyramids. This is a tunnel that was excavated by Saburo and Rubén Cabrera into the Pyramid of the Moon, which allowed them to reconstruct the stages of the history of the development of the Moon Pyramid.

[00:52:42.99] It was the earliest one. And you couldn't measure the expansion of the Teotihuacan state and city as they enlarged the Moon with each excavation. Growing up around all this was a young woman, so Nawa Sugiyama, she accompanied her father to Teotihuacan, ultimately came here.

[00:53:01.38] Another Harvard graduate who would go on to do her own dissertation research using remains from those Moon Pyramid excavations, where she analyzed the animal bones. What, to me, has been really striking about these studies of the monumental architecture at Teotihuacan is the sophistication by which, even without extensive written documents, the archaeologists have been able to get an understanding of the cosmology and political ideology of this ancient city.

[00:53:29.73] She looks at animal bones. She actually used MRI, isotopic analyzes, detailed contextual studies to talk about how these animals and the images of the animals help sort of empower the pyramids as great temple mountains that bring moisture and nutrients to the world. And a very sophisticated, abstract argument that comes out of looking these bits and pieces of things we find in the ground.

[00:53:56.46] To the most recent of the pyramid excavations, only this one's going below ground. The archaeologists working around the Feathered Serpent noticed that on a really rainy day, when the plaza flooded, there was water that kept going down a hole, Sergio Gómez investigates that hole.

[00:54:13.55] And discovers that there was this great tunnel excavated down under, and underneath the Pyramid of the Feathered Serpent. I had the opportunity to see the inside of it, but I'll make two comments. First of all excavating, this tunnel by the Teotihuacan, was this with monumental archeology done underground.

[00:54:31.88] And it was monumental archeology by Sergio Gómez and his colleagues to excavate and study this and the offerings that have come from it. Out of it has come now a slight modification of our interpretations of ideas, because he argues that this tunnel was a place of rituals.

[00:54:49.82] And what they did was when they finished building the Feathered Serpent Pyramid, they moved these rituals above ground. And these were rituals tied into celebrating Teotihuacan as the place where time began. And where the government was created.

[00:55:04.40] Here we've had another project done at the Pyramid of the Moon. Oops, gone here in the wrong direction. Here is the tunnel underneath the Sun Pyramid. The Sun Pyramid work has been done by Alejandro Sarabia, also further working on this ideology and the meanings of these pyramids.

[00:55:23.95] Two of the most recent projects involving two archaeologists here at Harvard, Nawa Sugiyama, who got her degrees from here, and is now holding her own tenure line position. And Bill Fash, in the Las Columnas Project, and David Carballo, who's also sitting here.

[00:55:38.76] Again, on these issues and questions about Teotihuacan governance. And the details of their story are yet to be told, as they're continuing into the field. But I think this slide also captures the image of the archeology as a collaborative endeavor at this great ancient city.

[00:55:56.28] And now I just want to kind of conclude the latter part of my talk about talking about that to understand Teotihuacan as a city, you can't just look at the city. You have to go out into the countryside. And out in this countryside-- and this was a map that Bill Sanders originally created-- they had to provision the city.

[00:56:12.88] They had to bring resources in from the outside areas of the city. And that probably is what encouraged the colonization of selected parts of the Basin of Mexico, because when Teotihuacan pulled everybody into that city, there wasn't anybody out there to bring resources into this city. There wasn't an infrastructure to do it with.

[00:56:33.03] They had to create it. And Justin Jennings is an archaeologist in Canada, who's written, I think, an important book, because he makes the argument that maybe these early cities made states, instead of early states making cities. That in trying to create an infrastructure in order to provision themselves, they had to come up with administrations.

[00:56:52.02] They had to form colonies and create this larger entity that we call the state. And at its height, Teotihuacan probably governed an area of central Mexico that had between 300,000 and 500,000 people living in it.

[00:57:08.10] Extended to the south into the cotton growing areas, extended over to the west, and to the east, where David Carballo has worked, along major trade routes to at least control or assert its authority.

[00:57:22.63] And this is a reconstruction of what the settlement looks like at the time that Teotihuacan is at its height. And we'll notice something else. Is that out in the countryside, our sites that are now being built with Teotihuacan-type architecture. This is the remains of a Teotihuacan mound that's underneath a chapel north of the city.

[00:57:44.50] You can see the plaster floor. This was done as part of a salvage project. This is another salvage project located to the northwest of Mexico City. The outlines of Teotihuacan rooms and plaster floors.

[00:57:57.58] And that brings me to another point. And that is 85% or 90% of the thousands of sites that were found on the archaeological surveys had been covered over by the growth of Mexico City and surrounding cities. So the maps and things that were done in the 1960s and 1970s, and collections made in combination with salvage archeology is really how we're going to understand the larger regional context of Teotihuacan.

[00:58:23.83] But this is another Teotihuacan period site along its trade route. And finally, to the work of David Carballo, that has finally helped to resolve a big debate about how important was the role of making Aztec tools to the economy of Teotihuacan?

[00:58:40.39] We knew there were concentrations of obsidian, but there were great debates about whether Teotihuacan attempted to monopolize the obsidian industry all over Mesoamerica, or maybe it was just the trash of a few flintknappers.

[00:58:52.69] And finally, after 30 years of arguing about it, David Carballo and Ken Hirth decided to actually excavate one of these and resolve it. We certainly have-- these are concentrations of workshops. But we now know from technological studies, it doesn't take very many people to mass produce lots of obsidian tools.

[00:59:08.65] And this is part of David's larger investigations of the Tlajinga neighborhood. This is the obsidian source that lies near Teotihuacan. We now recognize that markets and commerce were part of Teotihuacan's economy, at least within the city.

[00:59:22.87] And these are bowls that they imported, that Evelyn Rattray originally identified. This thin orange pottery is made in southern Pueblo. And the bowls were meant to be stacked, to be carried by traders from southern Pueblo into Teotihuacan and other sites.

[00:59:36.67] And this is an image from an outlying site that was dug in the 1950s, that has brought us, also, a new understanding of Teotihuacan's larger regional relationships, as maybe not as centralized as we once thought they were. The site of Cerro Portezuleo was dug in the 1950s. It has a small Teotihuacan platform on it, Teotihuacan style ceramics, This little water jar.

[01:00:02.38] They're imitations. They're copies of what was made from Teotihuacan. But what we discovered when we reanalyzed the material from this excavation is that the people there were copying Teotihuacan, but they were actually importing half as many ceramics from the western side of the Basin of Mexico as they were from Teotihuacan.

[01:00:22.99] That Teotihuacan did not really dominate the regional economy and they were bringing things in from outside. So we have a more complex, I think, picture that's being painted of its regional relationships.

[01:00:35.92] And now, I'll say just a little bit about the founding to bring me to one of our last and more recent PhDs out of Harvard archeology. Thanks to an undergraduate student at Dartmouth, who got interested in doing material science studies, she analyzed some of the early village pottery that Bill Sanders had collected in 1961 from a site called Altica.

[01:00:59.44] We recognized, and she identified, that some of this pottery was imported, but from only knows where, and we didn't even know whether this site existed. We went back into the field, found it, with my colleague, Wes Stoner, and this is Bridget.

[01:01:12.22] She was an undergraduate student at Dartmouth, so she's dressed in green here, for her thesis presentation. Of course, she would now be dressed in crimson. But at the time, some of her blood, at least, still runs green. And it was her honors thesis research that launched our project, that dated for the first time the earliest farming villages at 1250 BC.

[01:01:33.61] Maize farmers move into this area. They are part of a larger exchange networks. So the trading systems that Teotihuacan took to a whole new scale were established from the beginnings of these earliest villages. We came to understand that even this early village was not socially homogeneous.

[01:01:52.27] We found one individual who had been buried with a jade bead. And I've worked with a lot of sites out in the hinterlands, and at Teotihuacan, and I never found a jade bead in a village or site. But here, these earliest villagers had access to them, as well as to a little possum pot.

[01:02:08.02] And to the final piece of our story about Teotihuacan and its beginnings and its origins, when I was a graduate student, the story line when that Teotihuacan grew so big because the city of Cuicuilco was destroyed by a volcanic eruption.

[01:02:23.39] Well, volcanic eruptions did have an impact on the city. But we now know that volcanic eruptions probably lead people to flee to Teotihuacan, it didn't necessarily destroy its, perhaps, biggest rival. But when Popo shot off its head, the impact it might have had was actually to cut off the trade routes of Teotihuacan biggest rival city, Cuicuilco.

[01:02:47.53] And René Millon and had made a very astute observation from the mapping project at Teotihuacan. In that when they laid out the Street of the Dead and they reoriented the city, the only low pass out of the Basin of Mexico is through the Teotihuacan Valley, where you don't have to go over steep mountains.

[01:03:07.17] And he said they essentially laid out the city so that it was right at this pass. You didn't have to control the state merchants. Anything moving in and out of that part of the region would go through Teotihuacan. And moreover, if Cuicuilco's trade routes were blocked by the lava flows and the ash flows from Popocatépetl, that would have given Teotihuacan even more of a strategic advantage.

[01:03:34.11] And so I'll conclude with my final slide. Is one that I take, that Teotihuacan, even after its collapse and destruction at AD 550, continued to be part of the historical memory of later states and cities. It has continued to be part of this historical consciousness of Mexico, part of their own ideology of the modern nation-state, and their very deep and rich history.

[01:04:01.08] And that history extends as far north to a little town of Hanover, New Hampshire, in which José Clemente Orozco was invited to be the visiting artist at Dartmouth, early in the 20th century. And if you've never had the opportunity to see the only national landmark in the state of New Hampshire, it is the Orozco murals in the library at Dartmouth, where he has a room bigger than this one, which are covered with his view of modern and ancient history.

[01:04:30.27] And this is where he paints the Pyramids of the Sun and Moon and the rising of the great figure of Quetzacoatl. And David told me today there's at least one interpretation now, around that maybe this was known as the City of the Feathered Serpent.

[01:04:43.39] Orozco didn't know that when he painted it, but perhaps he captured something more about the city's identity. He thought it was a Toltec city, but now we know it takes much earlier than that. So thank you very much.

[01:04:53.64] [APPLAUSE]