Clifford T. Brown

The fractal geometry of ancient Maya settlement

Abstract Ancient Maya settlement patterns exhibit fractal geometry both within communities and across regions. Fractals are self-similar sets of fractional dimension. In this paper, we show how Maya settlement patterns are logically and statistically self-similar. We demonstrate how to measure the fractal dimensions (or Hausdorff–Besicovitch dimensions) of several data sets. We describe nonlinear dynamical processes, such as chaotic and self-organized critical systems, that generate fractal patterns. As an illustration, we show that the fractal dimensions calculated for some Maya settlement patterns are similar to those produced by warfare, supporting recent claims that warfare is a significant factor in Maya settlement patterning.

Correlated walks down the Babylonian markets

To investigate the evolution of market dynamics in different stages of historical development, we analyze commodity prices from two distinct periods —ancient Babylon, and medieval and early modern England. We find that the first-digit distributions of both Babylon and England commodity prices follow Benfords law, indicating that the data represent empirical observations typically arising from a free market. Further, we find that the normalized prices of both Babylon and England agricultural commodities are characterized by stretched exponential distributions, and exhibit persistent correlations of a power law type over long periods of up to several centuries, in contrast to contemporary markets. Our findings suggest that similar market interactions may underlie the dynamics of ancient agricultural commodity prices, and that these interactions may remain stable across centuries in two distinct historical periods.

Utility and Limitations of Portable X-Ray Fluorescence and Field Laboratory Conditions on the Geochemical Analysis of Soils and Floors at Areas of Known Human Activities

Abstract Portable x-ray fluorescence (pXRF) technology can be implemented in soil geochemical analysis for faster and more efficient testing of trace metals in soils. The level of soil phosphorus (P) is one of the major indicators of human activities related to food distribution, preparation, and waste disposal. Unfortunately, the low x-ray energy level of P and other light elements requires extensive sample preparation that may preclude pXRF as a field laboratory tool for P measurement. The high silicon content of soil causes serious interference in P analysis, yielding data of little value in midden prospection or activity area analysis. The Mehlich II or the Olsen bicarbonate extraction of soil samples can be conducted in a field laboratory providing excellent quality data. For pXRF analysis of soil samples in the field laboratory, it is recommended that soils are air-dry, and aggregates crushed, sieved (<2 mm), and mixed for better accuracy and reproducibility. Gridded soil samples from the central plaza of Telchaquillo, a contemporary village in Yucatan, were analyzed by the Mehlich II method for P and by pXRF and DTPA (diethylenetriaminepentaacetic acid) chelate extraction for trace metal concentrations. Areas of high P concentration were associated with an eatery and with two butchering posts. High DTPA extractable iron, copper, zinc, and manganese concentrations near the butchering posts were likely associated with the remnants of blood from butchered animals. The distributions and locations of elevated Fe concentrations were different for DTPA extractable Fe and pXRF total Fe and can be attributed to the different forms and solubility of crystalline iron in soil.

Determining hominid handedness in Lithic Debitage: A review of current methodologies

Abstract Handedness is inextricably linked to brain lateralization and language in humans, and identifying handedness in the paleo-archaeological record is important for understanding hominid cognitive evolution. This study reports on experiments for identifying knapper handedness in lithic debitage using three previously established methods: , and . A blind study was conducted on lithic debitage (n = 631) from Acheulean handaxes (n = 10) created by right- and left-handed subjects. Blinded handedness predictions for flakes were compared to their true handedness in order to assess each methods reliability. In order to test replicability, multiple observers classified a sample of flakes and inter-observer agreement was assessed. None of the methods were better than chance in predictive accuracy, and there were significant issues with inter-observer agreement. This study suggests that identifying knapper handedness in lithic debitage is extremely difficult, but also that some existing methodological issues may have simple solutions; suggestions for future research on this topic are provided.

Hunter–Gatherers Optimize Their Foraging Patterns Using Lévy Flights

We present evidence that human hunter-gatherers employ foraging movement patterns that are described by the statistics of Levy flights rather than by conventional Gaussian statistics. Human movement across the landscape is not usually considered an anthropological problem as such. For example, Green (1987, p. 273) observed that the way foragers move between resource patches has been the subject of little quantitative work. Nevertheless, movement patterns influence not only foraging itself but also cultural diffusion, demic diffusion, gene flow, and perhaps migration into virgin territory. So the discovery of Levy flights in foraging patterns carries implications for various theories in anthropology, including optimal foraging theory as applied to hunter-gatherers and by extension for archeological models of human subsistence settlement systems in prehistory. Moreover, it may help us understand the processes of diffusion and migration. Here, however, we focus our discussion on the implications for optimal foraging theory in cultural ecology and archeology.

Capital in the First Century: The Evolution of Inequality in Ancient Maya Society

We investigated the evolution of inequality in ancient Maya society using the sizes of houses as a proxy for household wealth. We used several mathematical and statistical methods to study the distribution of wealth at four major archaeological sites in the Maya lowlands: Komchen, Palenque, Sayil, and Mayapan. We calculated the Gini coefficient and the probability density function of the distribution of the house sizes as a measure of the wealth distribution at each site. We found that the wealth distributions had some characteristics of an approximate power law at all the sites, yet the exact distributions were statistically different from each other. The results indicate that the evolution of Maya culture across these sites cannot be understood as simply dependent on a monotonic evolution of the wealth distribution with time but should rather be explained by the historical circumstances surrounding each community. Specifically, the analyses show that, before the evolution of urban, state-level society, significant inequality existed in the Late Preclassic period, but a Pareto distribution either had not emerged or was incipient. In the Late and Terminal Classic periods, economic inequality became increasingly pronounced, while in the succeeding Postclassic period inequality ameliorated, although it seems that poverty prevailed.

Reflections on Metaarchaeology

The peripatetic itinerary of Lester Embree’s long career has taken him to some of the less frequented corners of the academy and to some even more isolated locales beyond the ramparts. He is widely known for his contributions to several branches of phenomenology, but some of his colleagues in philosophy may be but vaguely aware that he has investigated and written extensively on philosophy in archaeology. In this chapter, I take the reader to this less-frequented quarter of Lester’s philosophizing.