Thursday, September 21, 2017

Regional Clay Sampling

Angela Huster

This summer, I spent a week taking twenty-eight clay samples from across the Toluca Valley and immediately adjacent areas for INAA analysis. Don Cato, one of our local crew members from the excavation, helped by driving in incredibly convoluted loops around the area, and patiently explaining to  bystanders about what I was doing.

I kept crossing the construction route of another major water line to supply Mexico City. Occasionally, it was useful, such as here, where I needed a sample from below substantial modern fill.
These samples should help us identify where our previously sourced archaeological ceramics were made. Because there are only three other sites in the region with sourced ceramics, we have several chemical clusters in our archaeological ceramics that probably represent particular subregions, but we don't know where on the physical landscape those subregions are. More specifically, the new clay samples should help with three specific questions:

What chemical elements are the most geographically variable across the Toluca Valley and therefore the most useful for identifying source areas within the region?

Are the areas immediately to the south and west of the Toluca Valley likely sources for several of our "probably non-local" groups?

Are clays from the west (Toluca Valley) side of the mountain range between the Basin of Mexico and the Toluca Valley similar enough to Basin clays that they could explain some of our groups of Aztec-style ceramics that don't quite match local the very large existing reference data set for the Basin of Mexico?

Soil color and texture recording

Monday, April 7, 2014

Calixtlahuaca’s Market Brought to Life!

By Brad Andrews
           In my earlier blog on how art and archaeology work together, I summarized the work of Michael Stasinos, professor of Art at Pacific Lutheran University. Michael has provided our project with a means of artistically bringing to life the city of Calixtlahuaca based on the archaeological efforts of the Calixtlahuaca Project. He has now finished the market scene, a site-wide shot of the Calixtlahuaca cityscape with a marketplace in the foreground. As I pointed out before, Calixtlahuaca’s actual marketplace has not been identified, but Mesoamerican archaeological and ethnohistoric scholars agree that it was an extremely important economic institution throughout Central Mexico and beyond (Smith 2003). By the time of the Spanish conquest the market was an important component of what is referred to as the highly commercialized Postclassic Mesoamerican world system focused on the Basin of Mexico (Smith 2001). As applied to the study of prehistoric societies, the world systems concept refer to a macro-regional network of trade that linked individual political units - societies – into larger functioning units. For Prehispanic Mesoamerica, it has been argued that the market was the primary means by which people provisioned themselves with daily material necessities, both utilitarian and ceremonial.

As I mentioned in my previous blog on the topic, Michael’s challenge began by selecting a photo of Cerro Tenismo, upon which Calixtlahuaca is situated, that provided a “sense” of the whole, but enabled the incorporation of details in the foreground. The foreground is the focal point of the market scene, which he masterfully brought to light in consultation with those of us working on the Calixtlahuaca Project. The details of the market-focused daily activities were inspired by other ancient Mesoamerican market scenes, photographs of modern Mexican markets, and ethnohistoric information from a variety of sources. Hours of painstaking revisions were necessary to give full magic to the final product. Besides the market, he incorporated a reconstruction of the monumental Structure 4 (pyramid complex in the central part of the scene), the hillside populated with domestic households, vestiges of the water control ditches that drained the site during the rainy season, temples that occupied the top of the hill (complete with smoke produced by the probable burning of copal incense), and an ethereal skyscape of clouds, complete with birds drifting round and about. Note the increased density of households in the upper left-hand portion of the cerro. This detail depicts the variation in the layout of the urban center that was identified during the project’s survey efforts. Lots to see here, much of which is unfortunately obscured at the scale needed for this posting.

We extend many thanks to Michael Stasinos for his invaluable contribution to our project. We hope you agree his efforts were well worth it!

Smith, M. E.
            2001    The Aztec Empire and Mesoamerican World System. In Empires, edited by S. E. Alcock, T. N. D'Altroy, K. D. Morrison and C. M. Sinopoli. Cambridge University Press, Cambridge.

            2003    The Aztecs. Second Edition ed. Blackwell Publishing, Malden, Massachusetts.

Wednesday, January 8, 2014

What's new for Calixtlahuaca ??

It's a new year --  2014  --  and our analysis of the findings from our fieldwork at Calixtlahuaca continues.

We will try to get some new material posted soon. But in the meantime, check out some of our past posts. These cover several years, from our initial excavations in 2007 up to our current analyses at ASU:

The life and times of Burial 4 (written by anthropology major Kea Warren)

Sounds from the past: The bird-whistle from Calixtlahuaca  (have you ever heard an Aztec musical instrument, 500 years old, played?)

Gambling, tortillas, and Spaniards in hats

Using an artistic touch to bring Calixtlahuaca back to life

The 1563 calendrical relief

Working on ceramics in Toluca

Thursday, October 3, 2013

Subsets and Samples

By Mike Smith, with comments from the peanut gallery by Angela Huster
After a rather involved set of phone conversations and emails among various project members trying to establish the frequency of green obsidian at the site during each phase, we realized that half our problem was the we were working with different samples. We had defined the Domestic Context Sample of lots strongly associated with dated houses several years ago, but any analyses that wanted to work with a larger sample were a free-for-all. 

Based on Mike's previous projects in Morelos, we defined five samples based on their value for the analysis of domestic artifacts and conditions. These run from the Domestic Context Sample, (now called Domestic Sample 1, or DS-1), which consists only of well-dated midden deposits, to DS-5, which is the entire sample of all excavated contexts at the site. In addition there are other samples of lots that make sense for particular analyses or materials. Most of these samples are nested; e.g., all other samples include DS-1, and DS-5 includes all other samples. Samples DS-3 and DS-4 intersect in a non-nesting fashion, however.

DS-1 (the Domestic Context Sample).   178 lots.
             This sample consists of well-dated midden deposits associated with houses. It can be subdivided into domestic components; that is, deposits from a single phase in a single unit. It was designed to provide a robust sample of materials from contexts with abundant artifacts for optimal quantification. This sample is used for:
      Household comparisons of ceramic type frequencies.
·         Ceramic type frequencies for the Aguas Celestiales chapter

It is also the source of sub-samples for particular technical analyses, including:
Ceramic attribute recording

·         Obsidian source samples
·         Ceramic petrographic samples
·         Angela’s NAA samples

DS-2 (the Extended Domestic Context Sample).  340 lots.
            This sample extends the domestic context sample to include other lots dating to the same phases at individual units. Units without representation in the domestic context sample are not included in DS-2. The advantage of a larger sample is offset by the inclusion of contexts such as fill and colluvial overburden whose association with the occupation of a house is less secure. This is used for:
·         Interhousehold comparisons of rarer items in Angela’s dissertation analyses – ground stone, copper, jewelry, whorls, and molds

DS-3 (the all-Phased sample)  1,146 lots.
            This sample consists of all lots phased to a particular period. It includes the transitional or uncertain phases (3, 5, and 44*) and phase 1 (pre-Postclassic). This is a much larger sample than DS-1 or DS-2, and its value lies in the fact that it includes the maximal number of lots that can be phased. Many of the lots have not had their ceramics classified; they are phased through stratigraphic position or associations with lots dated from their classified ceramics and/or radiocarbon dates. Its disdvantage is the inclusion of many lots whose direct association with the house occupation of each unit is more tenuous (fill, overburden, etc.). Its primary use is for comparing frequencies of rare artifacts. It is used for:
·         Rare artifact types by phase for the general project

DS-4 (the Classified Sample)  664 lots.
            This is the sample of lots whose ceramics have been classified. It has two related disadvantages compared to sample DS-2: many of the lots have not been phased; and many of the lots have only a few sherds. It is not used in any analyses.

DS-5  (all Excavated Lots).  1,668 lots.
            This is the total number of lots that were excavated. It includes many tiny lots from Alex’s soil sampling, lots from architectural excavations, and other small lots whose value for artifact analysis is minimal. It’s primary use is to generate inventories of all excavated artifacts of a given type, irrespective of phasing or quality of context. This is useful for descriptive purposes (i.e., we want to describe all of the figurines, not just the ones that fall into a more restricted sample), but not for making comparisons among units or parts of the site.

The following diagram shows the relationship among these samples.
 If anyone needs to know which samples their data fall into, please contact Angela.

Tuesday, July 2, 2013

Working on ceramics in Toluca

Mr. Monkey-Helmet
I'm in Toluca for a few weeks working in our lab at the Colegio Mexiquense. I am wrapping up a variety of final tasks with our ceramics. One thing I am doing is organizing the miscellaneous ceramic forms, checking catalogs, recording attributes, drawing the artifacts, and taking photos. Here are a few photos to show what I've been doing.

The first photo is a monkey face, someone I call Mr. Monkey-Helmet. This is classified as a ceramic appliqué, which means it was stuck on the side of some object. In the profile view you can see the projection where this attached to the wall of the vessel. The problem is, what kind of vessels had monkey faces sticking out their sides? I really don't know (let me know if you have a

 Next we have some tobacco pipes. These little pipes were most abundant in western Mexico, among the Tarascans and other cultures. We found more pipes than I did in my earlier excavations near Cuernavaca, but they are still pretty rare items. Not all the houses had pipes, but since they are rare it is tough to tell whether this is significant or not.

Here are a few stamps. Ceramic stamps, like the one on the top left, are common at Aztec sites in the Valley of Mexico and in Morelos. These were regular household items at Yautepec and the other sites I excavated near Cuernavaca. But they are quite rare at Calixtlahuaca. In fact, the two on the left are the only Aztec-style stamps we excavated. The rarity of stamps at  Calixtlahuaca is one of many indications that the site was not closely integrated with the styles, culture, and practices of the Aztec heartland in the Valley of Mexico. My Morelos sites, on the other hand, matched the materials and styles of the Aztec center much more closely. The object on the right is unusual. The design does not match Aztec stamps, and it lacks a tab on the back. If you have any suggestions about what this may be, please let me know. Maybe it is from an earlier time period.

Tlaloc vessels
When he excavated at Calixtlahuaca in the 1930s, José  García Payón found a bunch of offerings of Tlaloc Vessels (tall, crude, ugly vessels with Tlaloc faces) in Temple 4, which then became known as the Tlaloc Temple. We found a few fragments of probable Tlaloc vessels in our excavations, but not very many. If you have seen the Tlaloc vessels from offerings at the Templo Mayor in Mexico City, these crummy sherds look pretty pathetic. Ah, the curse of household archaeology. We excavate fragments of everyday items, and rarely fine a beautiful complete object worthy of a museum. Oh, well.

Imports from Morelos

And finally, a photo of sherds from vessels imported from the state of Morelos. Contemporary sites in Morelos have move imports from the Toluca Valley than the reverse. Aztec-period houses in Morelos have a much higher number of imports overall, and imports from a larger number of places, than the houses at Calixtlahuaca. One interesting thing is that these Morelos imports span the entire sequence. At the top right is Morelos-Puebla Black-on-Orange, an Early Aztec type, and the two bottom decorated sherds, Morelos Type I, are from the final half of the Late Aztec period in western Morelos.

Brad Andrews is down here too for a few days, checking the obsidian. Next week I return from the 70 degree weather of Toluca to the 115 degree heat of Phoenix.

Wednesday, April 24, 2013

The Life and Times of Burial 4

This is the second post by this semester's student volunteers on bioarchaeological research at Calixtlahuaca.

This post includes photographs of human bone.

By Kea Warren

                Bioarchaeologists work with the traditional archaeologists to try to understand the way a group of people lived based on the remains they leave behind.  While working on the site of Calixtlahuaca in Mexico, Doctor Michael Smith and his team uncovered four full burials and the areas with broken bone rasps discussed in the previous post, all of which were later analyzed by Kristin Nado. Six burials is a relatively small sample size. While the site provides insight to the lives of a small group of people, archaeologists tend to prefer larger samples to understand trends and diversity among the population. From this smaller sample, bioarchaeologists can observe individuals and how those individuals lived, as will be discussed later, though the broader understanding of the group is limited.  
Map of Burial Locations
Three burials are physically close together, which may imply some sort of familial relationship between burials 5, 4, and 3 (which contain two adult males and an adult whose sex is unknown).  The two of these three bodies with preserved feet share a congenital condition known as non-osseous tarsal coalitions. This condition is also found in burial 2, which is from a different house excavation.  According to Nado, tarsal coalitions are when two or more tarsal bones are connected by bone or cartilage. This union of bone can be painful, and can also affect the sufferer’s ability to walk.  Further study of the inhabitants of Calixtlahuaca would provide a better understanding this condition in the region. If other remains were uncovered, it would allow bioarchaeologists like Nado to analyze if the condition is regional or possibly only specific to certain groups. DNA evidence of the relationship would strengthen the claim.
Beyond this potential familial relationship, the man in Burial Four has pathologies that are not found in the other burials.
Burial 4
                Burial Four is a male, who was between 25 and 29 years old at the time of death. Based on the man’s bones, Nado could immediately identify several pathological problems that give insight into the life of this man.  The tarsal coalitions are present, which would probably have caused pain. The lip of his acetabulum (colloquially known as the hip joint) appears to have extra articular surfaces. Nado has hypothesized that this may be due to a dislocation of the hip earlier in his life that was never realigned.  This would have been extremely painful, if not completely crippling to individual in Burial Four. The injury was sustained long enough before death that the bone had time to repair itself and try to accommodate the new location of Burial Four’s femur. This would have taken years.
Cyst in Burial 4's femur
His left tibia is also of interest.  It is unlike any other long bone found on site. Inside normal long bones is the medullary cavity, where the marrow is found. In Burial Four’s tibia, there seems to be a bubble of bone. The bioarchaeologists of SHESC remain puzzled as to what it could be, though it has been suggested that a cyst in the bone ossified, and that this is what remains.
                More can be learned from his skeletal remains. The teeth on the left side of his mouth are significantly more worn than those on the right, which Nado has suggested may have been due to use of his teeth for things beyond chewing. Was this for some task he performed because he could not walk?  Only Burial Five had a similar, albeit less prominent, wear pattern, also known as “bilateral asymmetry”. If more mandibles/maxilla can found at the site, more research into the presence of this wear could be performed. Was it specific to a group or family? What caused it? What does this tell us about social organization at the site and the relationship between Burial Four and others of his time? 
                While not everything that happened in life can be viewed in the skeletal remains of a person, bioarchaeology offers a glimpse into the lives of those long gone.  Thanks to Dr. Michael Smith, Angela Huster, Juliana Novic, Kristin Nado and the Calixtlahuaca team for their efforts to discover more about how people lived long ago.