Tuesday, November 22, 2016

Teotihuacan in the news: 1966 and 2016

I was looking for some biograhical material on Rene Millon, director of the Teotihuacan Mapping Project. I came across this story, from Popular Mechanics magazine in July 1966:

This was from the early days of the Teotihuacan Mapping Project, when they were in the middle of making surface artifact collections and digging test excavations.  And now, 50 years later, here is another press item from Teotihuacan:

Wow, knowledge really does advance through time. Back in 1966 no one had any idea they would find rabbit bones at Teotihuacan, and asking questions about animal keeping and diet like this were out of the question. Our analytical methods, as well as our stock of excavated archaeological contexts, are now far beyond what they were in 1966. This rabbit study, by a couple of archaeologists who started out as anthropology majors at Arizona State University, shows the kind of detailed questions we can now ask about the past (see bibliography below).

But as an archaeologist and scholar, I like to try to stand above the weeds now and then and take a broad perspective on the past. Archaeology is not just about mapping a site or figuring out what people ate for dinner. We need to take facts like these--established from rigorous fieldwork and laboratory analyses--and put together a broad view of life, society, and cities in the past. When we do this, it turns out that many things are not all that different from life, society, and cities today. This insight is the basis for the "Wide Urban World."

And when you turn to your turkey dinner for the Thanksgiving holiday this week, don't just think back to the Native Americans and Pilgrims and the first Thanksgiving meal. Think, instead, about the Mayas and Teotihuacanos of ancient Mesoamerica, the ones who first domesticated the turkey in the first place.


Somerville, Andrew D., Nawa Sugiyama, Linda R. Manzanilla, and Margaret J. Schoeninger
2016    Animal Management at the Ancient Metropolis of Teotihuacan, Mexico: Stable Isotopoe Analysis of Leporid (Cottontail and Jackrabbit) Bone Mineral. PLOS-One 11 (8): e0159982.

2016    Leporid management and specialized food production at Teotihuacan: stable isotope data from cottontail and jackrabbit bone collagen. Archaeological and Anthropological Sciences  (online first).

Pyramids of Teotihuacan in the 19th century

Tuesday, November 15, 2016

Energized Crowding Turns Cities into Social Reactors

What is is about cities that makes them exciting and dynamic? Things are happening in cities and people are attracted to them. As Jane Jacobs said, “Cities have the capability of providing something for everybody, only because, and only when, they are created by everybody.” Some cities never sleep. Cities are the setting for activities that just aren't found in smaller settlements. The more people in a city, the more activity and the more excitement. This is not just a feature of contemporary cities:  ancient cities like Teotihuacan were also bustling, dynamic, and attractive places. Architectural historian Spiro Kostof coined the term "energized crowding" to describe this aspect of urban life and society.

Energized crowding doesn't just describe the condition of life in cities - it describes the basic social forces that lead cities to grow and to transform life and society. This is the basis of the work on settlement scaling by the Social Reactors Project: me and Jose Lobo at Arizona State University, Scott Ortman at the University of Colorado, and Luis Bettencourt at the Santa Fe Institute. Check out our website. In our model, the process of energized crowding turns cities into social reactors.

As the number of people in a settlement increases, the number of potential social interactions grows at an exponential rate (see graph). As settlements grow larger, the effects of social interaction are amplified. These include positive, negative, and neutral effects. Let's start with the negative side of things. As we as individuals have to deal with more and more people, we get overloaded. Too many people, too much going on. This is called scalar stress. Some of the effects are highly negative--more people means more crime, more poverty, more social alienation. But scalar stress is offset by one of the big "nuetral" effects of growing settlement: the formation of neighborhoods. As cities grow, people adjust their activities so that they can live life on a smaller scale--the neighborhood. As I have said many times in this blog, neighborhoods are one of the very few universals of the urban experience. Here are a few posts on this (out of many.....):
 But there are also positive effects of energized crowding. Urban economists and economic geographers have known for a long time that when businesses and industries concentrate themselves in cities, it leads to economies of scale and thus major gains in productivity. These effects are called agglomeration effects, as in this diagram:
But it turns out that the positive effects of concentration and energized crowding are not limited to the modern industrial economy. In fact, they occur in cities before the industrial revolution, whether medieval European cities, or cities in the Roman or Inka empires. This fact alone shows that these effects are not due to factories, wage labor, advanced transportation, or other attributes of modern economies. In fact, these effects arise primarily out of the very act of social interaction within the built environment.

This realization was a real breakthrough in our understanding of the nature of city size and its role in generating the social and economic properties of cities. The key paper is Bettencourt (2013). Luis derives a quantitative model that predicts characteristics of cities based on their sizes, within a given region or urban system. The beauty of the model is that its conditions are general enough to fit cities before the modern era. In fact they also should work for non-urban settlements in agricultural village societies (and they do!).

Below is my diagram of energized crowding (from Smith 2017). When population grows, leading to higher densities, energized crowding increases. This can happen from regional population growth, or it can arise from the process of people moving into cities. The three results shown here are the negative, neutral, and positive outcomes of energized crowding.

In the time since Luis's 2013 article, our group has been scouring archaeology and history for cases where we can try out the model. Scott Ortman initiated this work with his studies of the settlement in the prehispanic Basin of Mexico. We've published a number of studies, and a bunch more are in the pipeline. Scott has even found the same scaling effects in village societies. The data requirements are heavy (a sample of 30 or more settlements from a given region and time period, with population estimates and other quantitative data to scale against population). If you think you know of any such cases, please let me know!

We have found the same quantitative relationships in modern and ancient settlement systems. This suggests that the same or very similar fundamental social processes operate when humans come together in settlements, whether today or two thousand years ago. Energized crowding--which is at a much higher level in larger settlements--has measurable effects on the density of settlement, and on the levels of economic and social outputs. In this figure, Graph A shows economic output measures for the modern U.S. economy, while Graph B shows wealth output for the ancient Inka economy. Quantitatively these two graphs are nearly identical. Both exhibit "superlinear scaling," with beta coefficients of 1.13.

So, how far can we push these relationships? Are they universal? Well, not quite. Hunter-gatherer campsites show very different patterns from the agricultural societies we have studied so far. This is something we are working on now. But for most systems we have examined, we find similar patterns, and when we apply Luis's model, we conclude that energized crowding turns settlements into social reactors.

For some other posts on the scaling work, see:
See our project website for more information.

Bettencourt, Luís M. A.  2013    The Origins of Scaling in Cities. Science 340: 1438-1441.

Cesaretti, Rudolf, Luís M. A. Bettencourt, Jose Lobo, Scott Ortman, and Michael E. Smith 2016    Population-Area Relationship in Medieval European Cities. PLOS-One: 11:(10) e162678.  .

Ortman, Scott G., Andrew H.F. Cabaniss, Jennie O. Sturm, and Luís M. A. Bettencourt
2014    The Pre-History of Urban Scaling. PLOS-one 9 (2): e87902.

2015    Settlement Scaling and Increasing Returns in an Ancient Society. Science Advances 1 (1): e1400066.

Ortman, Scott G. and Grant D. Coffey  2015    Universal Scaling: Evidence from Village-Level Societies. SFI Working Paper, vol. 15-10-044. Santa Fe Institute, Santa Fe. 

Ortman, Scott G., Kaitlyn E. Davis, José Lobo, Michael E. Smith, Luis M.A. Bettencourt, and Aaron Trumbo  2016    Settlement Scaling and Economic Change in the Central Andes. Journal of Archaeological Science 73: 94-106.  .

Smith, Michael E.  2017    The Generative Role of Settlement Aggregation and Urbanization. In Coming Together: Comparative Approaches to Population Aggregation and Early Urbanization, edited by Attila Gyucha. State University of New York Press, Albany.

Saturday, November 12, 2016

Anthropologist Anthony Leeds on cities

Anthony Leeds (1925-1989) was an urban  anthropologist back in the days when anthropologists made important contributions to understanding cities and urbanism (today "urban anthropology" means studying globalization in this city, studying neoliberalization in that city, but never looking at urbanism or cities from a comprehensive perspective).

Leeds was a productive ethnographer of the favelas of Rio de Janeiro. But for this blog, his claim to fame is the conceptual advances he made in understanding the nature of cities and rural-urban relations.I blogged about his ideas on rural-urban relations last year. I recently came across some notes I took on his publications, and they reminded me of some of his other creative ideas. Here I will go over three of his contributions, all of which are discussed in his 1979 article listed below: (1) his criticism of urban studies for being overly dependent on modern western cities and ignoring early and non-western cities; (2) his discussion of the different types of specialization that are associated with urbanism; and (3) his rural-urban framework.

(1)  Urban studies.  Here are some quotes from Leeds (1979). I sometimes think that in this blog I am channeling his ideas:
  • “Most current discussion of ‘urbanism’ and ‘urbanization’ can be shown to be ethno- and temprocentric and based on a historically particular class of urban phenomena and urban forms of integration.” (p.227)
  • “Generalizations are then made about ‘urbanism’ and ‘urban society’ based essentially on the urban experience of the past few hundred years, apparently without the realization that all urban phenomena of the past four or five hundred years have been ineluctably affected by the expansion of the capitalist system, in short by the development of what Wallerstein calls the ‘World System.’ The generalizations are, then, in fact not about ‘urbanization’ in general but about a single form of ‘urbanism’ or ‘urbanization,’ its evolution, and its acculturational by-products.” (228)
This is one of the critiques anthropologists make of the other social sciences: you cannot look only a modern western society and use that to generalize about all of humanity. Our ancestors lived for millennia in very different ways that people live today. If you want to generalize about humanity or human society, please do so from a reasonable sample! And while you are at it, please don't make up imaginary patterns of non-western or early human behavior (this last is directed at economists......).

(2)  Specialization.  People are always tossing around the term "specialization" when they talk about cities or complex societies. But there are different types and concepts of specialization, with different implications for society. We need to be clear which type we are talking about. Leeds (1979) identifies three types of spcialization:
  1. Specialization of localities. Different places within a system are often the settings for different types of activities or institutions. When a particular type of activity is limited to a few locations, and/or those locations are the setting for a high level of that type of activity, then we can say that the place is specialized. There is a differentiation of functions among places.
  2. Specialization of the components of technology. In this sense, the various aspects of technology can be specialized. Tools, materials, techniques, housings, tasks, activities, labor/skills, and knowledge can all be specialized, often (but not always) within a single large settlement.
  3. Specialization of institutions. This kind of specialization highlights differences between large complex societies and small-scale societies. In complex settings such as today's western nations, institutions such as government, religion, and education are specialized. But in small-scale societies, these institutions tend to be bundled together and their activity spread widely among the people. Instead of schools, everyone is responsible for education; instead of having an organized religion, religious knowledge and activities are widely distributed among people.
Leeds goes on to relate these to the concept of urban:  "I define 'urban' as the interacting confluence of all three of these specializations." (p. 230) I'll stop here, because I'm not sure this is a productive way to define urban or cities. But the concepts of specialization are important.

(3) Rural and urban. In the 1979 article I am writing about, Leeds briefly outlines his ideas of rural and urban, but the best discussion is in a paper from 1980. For Leeds, any society that has cities is entirely an urban society. That is, urban is not the opposite of rural. "Rural" refers to a set of specialized locations (agriculture, mining, forests, mountains) within an encompassing urban society. This is a functional definition of urban and rural: These are defined not as absolute entities of their own, but rather as places within a regional system have have particular functions.

All three of these ideas are productive, and they help us see urbanism not as a unitary phenomenon consisting of the cities on a Google map today. Rather, the urban world extended far back into the past, and around the world. And when we look at any urban society, we find that cities and their (specialized) activities transform the entire society. I cover this in greater depth in my older post.

When I discovered the work of Anthony Leeds, a couple of decades ago, a memory came back from my undergraduate days at Brandeis University. Leeds came to give a lecture at Brandeis, and my professors urged the anthropology majors to attend (just as I urge the majors to attend these talks today). Later, I recalled two things about that lecture. First, I didn't understand it at all! And second, I recalled the title, which I liked, "Some unpleasantries on peasantries."

I highly recommend the work of Anthony Leeds. Many of  his articles were assembled after his death into a nice edited volume (this includes the 1980, but but not 1979 paper). The introductory essay by Roger Sanjek (another outstanding urban anthropologist) is very good. 

The organization formerly known as the Society for Urban Anthropology offers the annual Anthony Leeds Award in Urban Anthropology. The society is now called, "The Society for Urban, National, and Transnational / Global Anthropology." What a joke, this is a signal of the decline of urban anthropology as a productive field (back in the days of Anthony Leeds) to a later diffuse existence where scholarship is not about cities, but rather cities are merely places to study other issues. Anyway, don't get me started here about the decline and fall of urban anthropology. Go look at the works of Anthony Leeds.

Leeds, Anthony
1979    Forms of Urban Integration: 'Social Urbanization' in Comparative Perspective. Urban Anthropology 8: 227-247.

1980    Towns and Villages in Society: Hierarchies of Order and Cause. In Cities in a Larger Context, edited by T. Collins, pp. 6-33. University of Georgia Press, Athens.

1994    Cities, Classes, and the Social Order, edited by Roger Sanjek. Cornell University Press, Ithaca.