Sunday, January 21, 2024

Amazonian "Garden Urbanism": A skeptical account

This new paper in Science is getting alot of publicity, and people are asking for my views (Rostain, et al. 2024) The paper presents fascinating new evidence for a complex settlement system in the Upper Amazon. The press releases say how surprising these finds are, but similar systems have been reported for various parts of lowland South America over the past decade. If you doubt this, please check out the citations in the article for some of these. My perspective on these earlier sites is that Prumers et al (Prümers, et al. 2022) are persuasive in making a case for urbanism in the Bolivian Amazon, whereas the argument made by Heckenberger et al. for urbanism in the southern Amazon (Heckenberger 2013; Heckenberger 2009; Heckenberger, et al. 2008) is deficient. Are these new sites “urban”? 

Follow me in a hypothetical situation here. Suppose you are an archaeologist who has found some complex settlements in a region (like Amazonia) whose indigenous inhabitants are traditionally thought not to have constructed urban or state societies. Here are two paths one might follow. First, you could read the literature on early urbanism, pay attention to how various concepts and models are operationalized in other regions, and then apply those insights to your data. You could test whether they match urban settlement in other areas, and explore whether urban concepts help advance knowledge of the setting. This would be a scientific approach to analysis and argumentation. Or, second, you could start by making a sensationalist claim that you have found urban sites, but without providing a definition of what you mean by urban. 

 I will start with the first option (the one not followed by Rostain et al). The most widespread urban definition is the sociological definition from Louis Wirth: a city is a permanent settlement with high population, high density, and social heterogeneity. These sites are not populous enough or dense enough to qualify. The authors report a platform density within settlement of 125 platforms/km sq; that is 1.25 platforms per hectare. If these were houses (the authors say this), and then at 5 persons per house, the density would have been 6 persons/ha, which is about the same as Tikal and other Maya cities. This low density is not too surprising; Maya cities also fail to fit Wirth’s definition. What about the alternative functional definition? Cities are settlement that contain activities and institutions that affect a broader hinterland (these are called ‘urban functions’). Maya settlements certainly fit here; palaces (and epigraphy) signal political rulership that extended beyond individual capitals, and big temple-pyramids signal religious functions, if people came from nearby smaller sites to ceremonies. These definitions are reviewed by lots of authors; for my contributions, see: (Smith 2020; Smith 2023:chapter 1).
Map of Kilampoe site

So, we can ask whether Sangay (the largest and most complex of the reported sites) had urban functions? The authors fail to present evidence for this. They make a claim that the various sites, large and small, showed “architectural and spatial homogeneity” (p.186). That would be a strong argument AGAINST an urban interpretation, since one of the features of urbanism is that different kinds of settlements have different kinds of activities and institutions. If Sangay had the same set of public buildings and spatial layout as smaller sites, I’m not sure how one could justify the label urban. 

Anyway, these are just some things that I would investigate if I were working with the data on these sites. They are certainly fascinating sites, and a site does not have to be considered “urban” for it to be interesting and important. Indeed, one of the features of my own theoretical approach to urbanism is that it is more productive to investigate a wide range of sites for urban and urban-like features than to try to police the boundaries of urbanism to find ways to keep out certain early sites. See my book on this approach (Smith 2023) 

 The second option—to make a sensationalist claim that one has found urban sites, without bothering to define urban or its material manifestations—is the one followed by Rostain et al. This may have led them to submit to the journal Science, whose coverage of archaeology has long emphasized sensational finds over scientific rigor (see my earlier posts, on the blog Publishing Archaeology, on problems with archaeological coverage in Science:: Post, "Rejected by Science" post: "How archaeology is distorted by Science magazine"). The authors close the paper with the claim that the areas of the central zones “are comparable in size to those of other great cultures of the past, such as Mexican Teotihuacan or the Egyptian Giza Plateau (page 188). I'm not sure why this is of theoretical interest, or what it has to do with a claim of urbanism; to me it is a piece of information that does not help in the task of analyzing these sites. Maybe this claim made sense to the editor and the single reviewer.  What if we make a comparison that does have some theoretical content? My diagram shows the height of some of the major pyramids of those other cultures, with the reported height at Sangay (4.5 m tall) shown in comparison. Why is this theoretically interesting? Read just about anything on early urbanism.

graph of pyramid size

We seem to have another case where the journal Science has published an unscientific analysis. Perhaps if your definition of science for archaeology focuses on the use of scientific techniques from the natural sciences, then this is science. But if your view is that science is an epistemology—a way of generating knowledge based on precision and operationalization of concepts, based on testing of hypotheses, then this paper is hardly scientific in orientation. Some of my views on these concepts of science can be found in: (Smith 2017), and in the blog posts that preceded that paper. There are three posts; 

 Heckenberger, M (2013) Tropical Garden Cities: archaeology and memory in the Southern Amazon. Revista Cadernos do Ceom 26(38):185-207. 
Heckenberger, MJ (2009) Lost Cities of the Amazon: The Amazon Tropical forest is not as Wild as it Looks. Scientific American 301(4, October):64-71. 
Heckenberger, MJ, JC Russell, C Fausto, JR Toney, MJ Schmidt, E Pereira, B Franchetto and A Kuikuro (2008) Pre-Columbian Urbanism, Anthropogenic Landscapes, and the Future of the Amazon. Science 321:1214-1217. 
Prümers, H, CJ Betancourt, J Iriarte, M Robinson and M Schaich (2022) Lidar reveals pre-Hispanic low-density urbanism in the Bolivian Amazon. Nature 606:325-328. 
Smith, ME (2023) Urban Life in the Distant Past: The Prehistory of Energized Crowding. Cambridge University Press, New York.

Friday, July 21, 2023

Why I rarely get excited by news stories about ancient cities

There is a media story going around this week about the discovery of a new, "hidden Maya city." Here is the story in the NY  Times:

The site was found, and is being analyzed, by Slovenian archaeologist Ivan Šprajc. The various Mayanists quoted in the NY Times article enthused over the site, calling it  "unusual", "a significant site" and "the real deal." I am skeptical. We used to have 100 Maya sites (a vague approximation), and now we have 101 Maya sites. I'd gladly take just 5 Maya sites, properly analyzed with quantitative data available for analysis, than 500 Maya sites with blobby maps (lidar or other).

This case points out the two problems I have with press releases on the discovery of new sites (or pyramids, or tombs, or hieroglyphic inscriptions). The first is the distinction between archaeology as a science of learning about past societies, and archaeology as a celebration of big, exotic finds from the past. Nearly all of the press releases on ancient cities are breathless about past finds, and say little about the scientific knowledge that has been (or has yet to be) established. The second problem is the exaggeration of the importance of finds by the media offices of universities and other organizations.


I'll start with my favorite story of this exaggeration of significance. A few years ago, a reporter emailed me and wanted to know my opinion of the new pyramid excavated at the Aztec site of Tlatelolco. I was puzzled. Tlatelolco is an Aztec ceremonial zone hemmed in by the modern buildings of Mexico City. It had a pyramid even larger than the major Templo Mayor of Tenochtitlan. Tlatelolco has been completely excavated! Where could they have found a new pyramid?

Excavators in the 1940s found about eight construction stages for the main double-stair pyramid at Tlatelolco (pictured above). The earliest platform, Stage 1, was below the water table, so they didn't uncover it. The earliest platform visible today is Stage 2. Everybody knew the Stage 1 platform was sitting there, underneath the excavated Stage 2 structure. The water table had gone down since the 1940s, so archaeologists decided to excavate the Stage 1 platform. The media office said they had found a new pyramid at the site! Give me a break.

Back to the science/exotic distinction for archaeology. In some of my writings, I distinguish "household archaeology" from "monumental archaeology." The former, which many of my colleagues and I pursue, uses a scientific approach to learn about ancient society and the activities and conditions of people in the past. Not just kings and elites but everyday people. We employ hypothesis testing and careful argumentation to make inferences about these things. Monumental archaeology, on the other hand, emphasizes the big buildings and elites of the past. This is the context of the NY Times article on Ocomtun, and the emphasis of the quotes by my Mayanist colleagues. 

In my prize-winning 2016 book, At Home with the Aztecs (Society for American Archaeology, Best Popular Book in Archaeology, 2017 I describe how the social and monumental approaches differ in their concept of what constitutes n archaeological discovery:

“A different kind of contrast between monumental and household archaeology involves the timing of the moment of archaeological discovery. In the former approach the major finds come during fieldwork: things like the opening of a tomb or the discovery of a new hieroglyphic inscription. But when excavating the mid­dens of ancient peasant farmers, excitement rarely reveals itself in the field—the houses are similar and the middens all look pretty much the same. The important discoveries come later, in the laboratory stage of research. The artifacts tell the stories of what people were doing and who they were.” (p.129)

For me, finding a new site is rarely exciting or notable on its own. But once the site is mapped, contexts are excavated, and artifacts are analyzed, then a new site might yield important scientific discoveries.

I am also skeptical of new research using lidar, which Mayanists like to say has "revolutionized" the field (that word is used in the NY Times article too). When the Mayanists can point to a body of rigorous scientific findings from the lidar data, then I'll pay attention. But, with the exception of a couple of studies, that is not yet the case. Lidar has given us lots of pretty maps, but very little data on demography or social organization (beyond statements that there were lots of people living in the jungle, something we have known since the 1960s). See my 2018 cranky post here: 

If you want to see what an explicitly scientific approach to ancient cities looks like, take a look at my new book (Cambridge University Press

, 2023):

To me, "science" with respect to archaeology does not mean that one uses "scientific" techniques. Rather, it is an epistemological label for research that is rigorous, quantitative, and based on testing. If you are interested, I did a series of 3 blog posts on this a few years ago:

I also published a paper on this topic, available here:

Saturday, January 14, 2023

Nailing my theses to the internet, part 2 of 2


This is the second of two posts on my fundamental “theses”: the basic principles of my approach to premodern cities and urbanism.  See the first post here:


(4) Cities and urban life are structured by the interplay between two sets of processes: centralized, or top-down, processes originate with kings, elites, and central institutions, whereas generative, or bottom-up, processes arise from the grass-roots actions of individuals not under the control or direction of institutions or authorities.


Urban life and organization is made up of a constant interplay of these two kinds of processes of change. My usage is based on common approaches in the social sciences outside archaeology.[1] I distinguish two types of generative process: Grassroots activity refers to the intentional efforts of people to organize and coordinate their activities in pursuit of a goal (Chapter 7). Spontaneous organization describes actions of daily life, including social interactions, that create some kind of order or outcome that was neither planned nor created by authorities (Chapters 3, 7). My prime example of this is energized crowding.

Figure 7.1, from Besim Hakim

While both top-down and bottom-up factors are typically in play, some realms are closer to the institutional or upper domain of society, while others lie closer to the generative realm. For example, most premodern urbanites paid taxes, and taxation is primarily an activity of the state, a top-down institution. While the generative actions of individuals and groups may affect tax collection, these are typically of less importance than the top-down demands at play. Political protest, on the other hand, is primarily a generative process; nevertheless, top-down forces may affect the nature and outcomes of protests. My discussion of urban life proper is divided along these lines: Chapter 6 focuses on institutions or top-down processes, and Chapter 7 is about generative processes. This division flows from my basic definition of cities as settlement where population and activities are concentrated.


(5) Social interactions within cities and other settlements create “energized crowding,” which is one of the fundamental causal mechanisms in urban life.


As in the case of Thesis #4, this principle also flows from my basic definition of cities. The importance of face-to-face social interaction, in the form of energized crowding, in generating social outcomes is a fundamental component of many theoretical approaches in the social sciences (Brower 2011; Glaeser 2011; Ostrom 1990; Storper and Venables 2004). This perspective has been developed into a set of formal theories with quantitative predictions, known as settlement scaling theory (Bettencourt et al. 2007; Pumain et al. 2006; West 2017). I have participated in one branch of this approach, which views cities as “social reactors” (Bettencourt 2013). We have extended research from contemporary cities into the deep past, revealing broad continuities in the role of settlement size between ancient and modern settlement systems. In this book I explore the nature and implications of social interactions for premodern cities.[2]


           An additional consideration that colors how some archaeologists write about ancient cities is what I call the “urban prestige effect.” As a legacy of rigid and universalist schemes of cultural evolution popular form the 1950s through the 1970s

(Service 1975; White 1959), many archaeologists assign a high value, with a high level of prestige, to the categories of cities and urbanism. This signals an unfortunate emotional association with the objects of their study (settlements). Urban sites are seen as “better” than non-urban settlements, resulting in attempts to categorize non-urban settlements as cities. Non-urban villages are not infrequently declared urban by one scholar or another, whether ancient sites like Çatalhöyük (see Case study 2, below) or modern Amazonian villages (Heckenberger et al. 2008). It is almost guaranteed that complex early settlements—such as the Tripalyan “mega-sites”—will be viewed as urban (Chapman and Gaydarska 2016; Diachenko and Menotti 2017), regardless of the nature of the evidence; see Chapter 2. This urban prestige effect only muddies the waters of premodern settlement analysis, contributing little to our understanding of the settlements in question, or to comparative urban studies.




Bettencourt, Luís M. A.

2013    The Origins of Scaling in Cities. Science 340: 1438-1441.

Bettencourt, Luís M. A., José Lobo, Dirk Helbing, Christian Kühnert, and Geoffrey B. West

2007    Growth, Innovation, Scaling, and the Pace of Life in Cities. Proceedings of the National Academy of Sciences 104: 7301-7306.

Brower, Sidney N.

2011    Neighbors and Neighborhoods: Elements of Successful Community Design. APA Planners Press, Chicago.

Chapman, John and Bisserka Gaydarska

2016    From Domestic Households to Mega-Structures: Proto-Urbanism? In Trypillia Mega-Sites and European Prehistory,  4100-3400 BCE, edited by Johannes Müller, Knut Rassmann, and Mykhailo Videiko, pp. 289-299. Routledge, New York.

Diachenko, Aleksandr and Francesco Menotti

2017    Proto-Cities or Non-Proto-Cities? On the Nature of Cucuteni–Trypillia Mega-Sites. Journal of World Prehistory 30 (3): 207-219.

Glaeser, Edward L.

2011    The Triumph of the City: How our Greatest Invention Makes us Richer, Smarter, Greener, Healthier, and Happier. Penguin, New York.

Heckenberger, Michael J., J. Christian Russell, Carlos Fausto, Joshua R. Toney, Morgan J. Schmidt, Edithe Pereira, Bruna Franchetto, and Afukaka Kuikuro

2008    Pre-Columbian Urbanism, Anthropogenic Landscapes, and the Future of the Amazon. Science 321: 1214-1217.

Ostrom, Elinor

1990    Governing the Commons: The Evolution of Institutions for Collective Action. Cambridge University Press, New York.

Pumain, Denise, Fabien Paulus, Céline Vacchiana-Marcuzzo, and José Lobo

2006    An Evolutionary Theory for Inerpreting Urban Scaling Laws. Cybergeo: European Journal of Geography  (article 343).

Service, Elman Rogers

1975    Origins of the State and Civilization: The Process of Cultural Evolution. Norton, New York.

Storper, Michael and Anthony J. Venables

2004    Buzz: Face-to-Face Contact and the Urban Economy. Journal of Economic Geography 4 (4): 351-370.

West, Geoffrey B.

2017    Scale: The Universal Laws of Growth, Innovation, Sustainability, and the Pace of Lifein Organisms, Cities, Economies, and Companies. Penguin, New York.

White, Leslie A.

1959    The Evolution of Culture: The Development of Civilization to the Fall of Rome. McGraw-Hill, New York.

[1] I wish to distinguish my usage of top-down and bottom-up from a particular archaeological usage in which “top-down” refers to studies of kings and elites, while “bottom-up” denotes studies of households. My usage, in contrast, is based on drivers of change and causal mechanisms (Chapters 3, 6, 7).

[2] The research and publications of the Social reactors project are presented at:

Nailing my theses to the internet, part 1 of 2

Martin Luther nailed his theses to the door of the church to mark the public expression of his ideas. I believe that scholars should similarly make their fundamental principles public. My book, Urban Life in the Distant Past, is built on a foundation of five “theses,” or fundamental principles. These describe the major outlines of my theoretical and comparative approach to premodern cities. In this post, taken from chapter 1, I describe the first three of my theses; the other two will be in my next post. This is the modern version of nailing one’s thesis to the wall (a custom that survives in Swedish universities, where they still must nail completed thesis to the wall!).


(1) Definitions are tools; one’s definition of city or urban depends on one’s goals and questions.


Scholars of cities today spend little time agonizing over how one defines the terms city and urban. In fact, they typically use the term “definition” to refer to operationalization: the measures that capture the phenomena scholars want to study. Premodern cities exhibit far more variability than modern cities in the size, form, functions, and activities; in addition, their political and economic contexts are more varied. For example, virtually all cities today exist within nation-states. But premodern cities could be part of a chiefdom, a city-state, an empire, or a weak state (Chapter 4). Cities today are embedded in a globalized, capitalist world system, whereas premodern cities could be part of a command economy, a small-scale commercial economy, or a far-flung globalized early commercial economy (Chapter 5). Because of this variability, the ways premodern cities may be defined also vary greatly. There is no “best” definition of city or urban (Smith 2020). This principle is often neglected by scholars of ancient cities, who may agonize over the “correct” definition of urban, or how to document and study the essence of cities and urbanism, which leads to my next principle.


            (2)  Do not reify the concepts of city or urban.


Cities and urbanism—particularly in the premodern domain—are not real things. Settlements, on the other hand, are real. They exist in this world. Archaeologists excavate their remains, and it is usually obvious whether a given site was a place where people resided. “City” and “urban,” on the other hand, are categories or concepts that we apply to some settlements, when it suits our goals. If we have different goals, we may use different definitions. In the language of philosopher John Searle (1995)

John Searle
settlements are brute facts, while cities are institutional facts. One of Searle’s examples is money. The fact that a piece of paper in my wallet has value and can be exchanged for goods and services is an institutional fact. It depends on the existence of institutions and beliefs that allow particular kinds of pieces of paper to be used to purchase things. But the physical properties of this same dollar bill—its ability to be folded or rolled up, or burned, or marked with a pen—are brute facts. They do not depend on an institutional framework or common beliefs within a community of people. There is no “brute fact” of “citiness” or “urbanity” as intrinsic attributes of a settlement, something waiting to be discovered; these are institutional facts that only make sense from a given perspective, with a given definition. The consequence of this principle is the following:


(3) The settlement should be the primary unit of analysis, not the city. We should acknowledge that some “urban” attributes and practices apply to non-urban settlements.


If settlements are “brute facts,” then it makes sense to use them as a basic unit of analysis. When our research shows that a given settlement was large and complex, or served as a hub in a regional economy, then we may want to classify it as an urban settlement; in Searle’s framework, this is an institutional judgment. The fact that some key features of cities also characterize smaller, non-urban, settlements is a further warning about the dangers of reifying the concept urban. Settlement scaling research shows that key quantitative outcomes of social interactions in settlements characterize both urban and non-urban settlement systems (Ortman and Coffey 2017); see Chapter 3. Similarly, comparative work on neighborhoods shows that this urban social-spatial unit is also found in non-urban settlements (Smith et al. 2015; Tuzin 2001); see Chapter 7. These findings suggest that we can proceed with analyzing settlements without agonizing over definitions or worries about whether or not they are urban.[1]

            See the next post, Part 2, for the rest of my theses.

Swedish theses nailed to the wall


Ortman, Scott G. and Grant D. Coffey

2017    Settlement Scaling in Middle-Range Societies. American Antiquity 82 (4): 662-682.

Searle, John R.

1995    The Construction of Social Reality. Free Press, New York.

Smith, Michael E.

2020    Definitions and Comparisons in Urban Archaeology. Journal of Urban Archaeology 1: 15-30.

Smith, Michael E., Ashley Engquist, Cinthia Carvajal, Katrina Johnston, Amanda Young, Monica Algara, Yui Kuznetsov, and Bridgette Gilliland

2015    Neighborhood Formation in Semi-Urban Settlements. Journal of Urbanism 8 (2): 173-198.

Tuzin, Donald

2001    Social Complexity in the Making: A Case Study Among the Arapesh of New Guinea. Routledge, New York.

[1] Perhaps ironically, this caveat has not stopped archaeologists—including me—from arguing about definitions of city and urban; see discussion below.