Bedding, hearths, and site maintenance in the Middle Stone Age of Sibudu Cave, KwaZulu-Natal, South Africa

Micromorphological analysis of sediments from the Middle Stone Age site of Sibudu Cave, KwaZulu-Natal, South Africa, provides a high-resolution sequence and evidence of site formation processes of predominantly anthropogenic deposits. This methodology allows for a detailed interpretation of individual anthropogenic activities, including the construction of hearths and bedding and the maintenance of occupational surfaces through the sweep out of hearths and the repeated burning of bedding. This analysis also provides a context for evaluating other studies at the site relating to magnetic susceptibility, paleobotany, paleozoology, anthracology, and studies of ochre.     

Assessing the applicability of portable X-ray fluorescence spectrometry for obsidian provenance research in the Maya lowlands

Recent innovations in portable energy-dispersive X-ray fluorescence (PXRF) spectrometry have increased its utility for the geochemical characterization of obsidian artifacts for archaeological provenance research. However, concerns over the utility of PXRF instrumental analyses have been raised, focused on the validity and reliability of the geochemical data produced. Here we adopt the framework of Richard Hughes (On Reliability, Validity, and Scale in Obsidian Sourcing Research, 1998), whereby reliability addresses instrument stability and issues of measurement while validity pertains to an instrument’s ability to discern geochemical source provenance. This is done in order to test the utility of PXRF instruments for archaeological provenance research. k-Means cluster analysis was used to test the accuracy of PXRF through statistical comparison of data acquired via laboratory and portable energy-dispersive XRF instruments. Multivariate analysis was employed to demonstrate obsidian source representation at two Classic Maya archaeological sites in southern Belize – Uxbenká and Ek Xux – and to test the validity of data obtained from a PXRF instrument in answering archaeological research questions pertaining to regional interactions between lowland Maya polities. Results suggest that portable XRF instruments produce internally consistent results. However, data acquired from a PXRF instrument are not statistically equivalent to other XRF instruments. This is to say that while PXRF is not a reliable technique, it is valid for questions pertaining to geochemical source representation.     

Recent Research in Western Mexican Archaeology

Western Mexico is vast and geographically diverse and has received far less attention compared to other areas of Mesoamerica. Research over the past decade allows the definition of four major subregions characterized by cultural factors and distinct historical trajectories. A large proportion of the research in western Mexico is still culture-historical in nature, oriented toward establishing chronologies and relationships between regions. But along with a number of recent efforts toward synthesis and consolidation, current theoretical research contributes to the study of mortuary patterns and social organization, alternative forms of social complexity, agricultural intensification, empire formation, state involvement in the economy, human-land relationships, and the interlocking relationship between migration and sociopolitical reorganization.     

The Tuskegee Syphilis Study and the scientific concept of racial nervous resistance

In 1932, the U.S. Public Health Service began a study of untreated syphilis among black men in Macon County, Alabama. This project, later known as the Tuskegee Syphilis Study, became one of the most notorious ventures of twentieth-century medicine. Much has been written on it. Historians have suggested that scientific racism strongly influenced the study. But specific links between earlier racial science and the scientific conduct of the study have remained unexplored. The examination in this paper of the concept of a racially determined resistance to syphilis in the nervous system establishes such a link. Discussion of nervous resistance to syphilis appeared in the medical literature in the early twentieth century as a conjecture about the natural inferiority of blacks. White physicians used the concept to interpret racial differences in neurosyphilis as evidence of the rudimentary development of the brain. A small community of African American physicians joined other national experts in syphilis who chose to explain apparent racial differences through alternate mechanisms. But the scientific advisors to the Tuskegee Syphilis Study favored the concept of a racial resistance to neurosyphilis and steered the early design of the study to help to elucidate it. The Tuskegee Syphilis Study was an examination of untreated syphilis, but it also became a demonstration of a putative racial characteristic of syphilis long considered evidence of the natural inferiority of blacks. An examination of the concept of racial nervous resistance and its influence on the research in Macon County helps to define the influence of scientific racism on this notorious medical study.     

Mapping ancient chinampa landscapes in the Basin of Mexico: a remote sensing and GIS approach

This paper uses remote sensing data to document a raised field, chinampa system adjacent to the Postclassic kingdom of Xaltocan in the northern Basin of Mexico. Various forms of landscape information; historic records and maps as well as remote sensing; are considered to understand the chinampa system. The remote sensing data examined include 1950s aerial photographs, Landsat 7 data, and Quickbird VHR, multi-spectral imagery. This article evaluates the utility of each of these forms of data to identify buried chinampa features and integrates them in a GIS to produce a map of Xaltocan's chinampa landscape. Canals of various sizes and hydrological positions comprised the chinampas and integrated the system together. Occupying at least 1500–2000 ha, Xaltocan's chinampa system represents the largest pre-Aztec, chinampa system in the Basin of Mexico.     

An experimental micromorphological investigation of bedding construction in the Middle Stone Age of Sibudu,South Africa

We conducted experiments to compare the micromorphological signatures of modern burnt sedge and grass bedding to laminated layers of carbonized material and phytoliths in Middle Stone Age deposits at the shelter, Sibudu. The experiments were designed to clarify the formation processes associated with the laminated layers and to investigate whether these previously identified layers of bedding were deliberately burned or not. The results indicate that the laminated layers were most likely produced by human activity related to the construction, maintenance and burning of bedding. Furthermore, our experiments demonstrate that large volumes of vegetal material could have produced the relatively thin, archaeological deposits of burnt bedding.