For a little over a month now, we’ve been discussing the 3D geometric morphometrics (shape analysis) of Caddo ceramics from the Vanderpool site in East Texas. While I still have much left to do with the analysis (i.e., find out which burial each vessel is from, and what “type” of vessels they are, etc.), I thought it time to provide an overview of what we’ve learned so far. While the results–much like the analytical procedure–will no doubt evolve as we continue to progress, I have reached a turning point in the analysis of the Vanderpool vessels.
A brief overview: over the last few weeks, we’ve learned that a significant amount of variation exists within the analytical realm of vessel form. Through the application of geometric morphometrics, we were able to segregate the ceramic population into groups of vessels that possess similar morphometric characteristics.
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3D geometric morphometrics of Caddo carinated bowls from the Vanderpool site.
This same procedure was followed for the remainder of the vessels at the site, and multiple groups of vessels were identified within the categories of jars, bottles, carinated bowls, and bowls. I decided to use a method of illustrating these groups that is similar to those used in phylogeny, but–to be clear–we’re not there yet. The illustration below highlights only those results from the analysis of geometric morphometrics, where each group was clustered accordingly.
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Results of 3D morphometrics of Caddo ceramics from the Vanderpool site; gray = anomalous, pink = jars, brown = bottles, green = carinated bowls, blue = bowls.
This is important for a number of reasons, particularly when it comes to current avenues of thought regarding vessel function and cultural transmission. The end goal of this endeavor is to couch these data within evolutionary theory (not cultural evolution); more specifically, within a morphometric phylogeny. This will require a lot more time with the 3D scanner, and a lot more theory-building. Among those tasks that need to be accomplished include something of a trade-in of the more traditional folk categories (like bowl, bottle, carinated bowl, etc.) for a vessel classification method that is more paradigmatic in nature.
If we’re successful, the morphometric phylogeny should help to clarify some of the questions that we have regarding the origins and the evolution of specific aspects (i.e., adoption and evolution of handles, etc.) of Caddo ceramic technology, and–similar to its’ counterpart in biological sciences–the phylogeny will continue to evolve as new vessels are discovered, and new collections are added to the analysis. What is particularly attractive about this approach is that it provides us with a method that aggregates data from numerous sites, museums, and repositories, providing us with a fresh look at some old data, and allowing us to compare them in a side-by-side analysis (albeit a virtual one).
The take-away from all of this is that we’re getting there. Given the spatial location and temporal assignment of the Vanderpool site, and the ongoing research endeavors at the CRHR (I’m currently scanning the Turner collection, which includes 16 more Caddo sites in the area), it will be interesting to see how–and whether–the temporal and spatial dynamics of vessel form can be found to correlate with the currently (although in need of an update) ceramic taxonomy.
Noteworthy aside: there are no compound bowls in the Vanderpool collection (if anyone needs a worthwhile thesis topic, I would invite them to explore that further).
Second noteworthy aside: the CRHR is currently exploring the incorporation of 2D geometric morphometrics into our current research design (using thousands of photos of Caddo vessels made available by Tim Perttula and Bo Nelson) – once we nail down a method, we plan to compare and contrast the 2D and 3D results using identical collections.
I don’t know about you, but here at the CRHR, we’re really getting excited about the future of Caddo archaeology!
**I will be taking next week off to participate in the 2013 NSF grant submission season (I’m certain that some of you will be in a similar situation), but I’ll be back the following week with images of a few newly-scanned vessels from the Turner collection.**