GIS 5103 Participation Assignment 1: GIS, Archaeology, and Human Movement Modeling

Fig. 2. The location of the Missaukee Earthworks (20MA11-12) and the twenty-nine contemporary, significant Late Prehistoric (AD 1200-1600) sites used as the focal node input for Circuitscape resistance analysis. (From Howey, 2011)

The article I read as an example of GIS used in the real world was “Multiple pathways across past landscapes: circuit theory as a complementary geospatial method to least cost path for modeling past movement” by Meghan C. L. Howey (Journal of Archaeological Science, 38 (2011), 2523-2535).  Howey uses the topic of population movement among the peoples of northern Michigan between 1200 and 1600 AD to test least cost path modeling and circuit modeling of this movement.  Specifically, she looks at the movement to and from the Missaukee Earthworks site, an important trade and ritual center.  Howey’s circuit model is run by an ArcGIS tool called Circuitscape.

The simplest version of least cost path modeling would consider only distance and topography, which, according to Howey, some researchers still do.  However, Howey also included water routes and land cover in her original least cost path analysis.  The output of a least cost path model is a single route that, based on the input parameters, represents the route of least resistance between two points.  A circuit model, on the other hand, considers the presence of multiple routes between two points in its analysis of the relative ease or difficulty of travel.  In other words, if site A and site B have a single route of medium resistance connecting them while site A and site C have five possible connecting routes of the same resistance, travel between sites A and C will be rated as easier than travel between sites A and B.  While distance is a factor, this may hold true even if site C is significantly further away than site B. 

The article’s tables and figures show an interesting comparison between the results of the two modelling strategies, but Howey concludes by emphasizing each tool has its strengths and weaknesses.  Circuit modelling is clearly useful in considering a larger portion of the landscape as potential routes of travel; humans are not perfect optimizers of their energies and surroundings, after all.  However, circuit modelling can overlook cases in which a single route is overwhelmingly preferred (such as water routes).  In the latter case, least cost path modelling would provide a more useful picture. 

The article may be a bit dry, I suppose, but I followed the suggestion to explore UWF’s library databases and went with a topic aligning with the archaeology track.  The article can be accessed at: http://dx.doi.org.ezproxy.lib.uwf.edu/10.1016/j.jas.2011.03.024.