An arid landscape for the past 55 Ma, the Namib Desert poses significant occupational challenges even today. These seemingly inhospitable landscapes, however, bear evidence of hominin occupation in the form of stone tool artifacts that, in areas, form dense surface scatters typologically representative of at least intermittent occupation from the Early Stone Age (ESA; Figure 1). Lacking in stratigraphic context these scatters have been largely overlooked, leading to a biased picture of early hominin distribution in arid environments the world over (Knight and Zerboni 2018). However, despite the challenges posed by these assemblages, their ubiquity offers unparalleled insights into hominin behaviour over longer time scales within these marginal arid environments: migrations, resource distribution and exploitation, and raw material use and discard, for example (e.g. Blumenschine et al. 2012). Having seen only minimal erosion rates over the past 135 million years (Biermann and Caffee 2001), the Namib offers a unique opportunity to explore these questions within a relatively stable landscape.
It is the more ephemeral hominin presence of the Namib Desert, as indicated by ESA artifacts, that this research is interested in. Identified ESA scatters indicate that hominins were choosing to move into marginal landscapes that exhibit significant prolonged water stress, but how, when and why they did so is poorly understood. This project proposes a combination of traditional and innovative techniques to begin answering these questions through the following objectives:
Locations within the Namib have been identified for the first exploratory season. (Figure 2) The dunes of Gobabeb will provide the first location. Previous work conducted by Marks (pers comm) has identified ESA lithic scatters distributed on two adjacent landscapes: dunes and plateaus. We will identify scatters that appear to be earlier stone age based on technological criteria. Specifically we will reevaluate the sites of Namib IV, Narabeb, Mnszechi’s Vlei, and Khommabes. The sites that most fit our research methodologies will become the focus.
The realisation of these objectives will provide a framework of understanding for the ESA occupation of the Namib: when and how were early hominins surviving within these marginal environments and how were they utilising these landscapes and the available resources? The development of desert varnish in the Namib will at this stage be assessed for feasibility but, should it be a success, samples will be taken further to develop a means of dating these highly significant, but poorly understood, surface scatters based on the relative growth of mineralized patination on the exposed artifacts.
This work is important for several key reasons: as with all areas of archaeology, human origins research is biased. Projects are predominantly focused in relatively easy-to-reach (and easy-to-work-in) areas and on in situ sites, with finds in these areas often leading to further investigation. This pattern is reflected by distribution maps, which show unrealistically empty landscapes in areas adjoined by rich evidence of occupation, and high densities of sites in areas with long histories of research. This bias undeniably affects interpretations of our evolution over huge timescales by relegating the contribution of certain landscapes. Recent attempts to redress the situation have led to significant progress, particularly through showing that the current environment of an area does not define those of its past (e.g. Drake et al. 2011; Petraglia et al. 2012). Similarly, Namibia sits in an area that has seen little systematic ESA research and is considered to lie on the peripheries of currently mapped occupation. Here we propose that this view is largely driven by the difficulties of working in challenging environments with little stratigraphic control. The instigation of the proposed methods, however, stands to change this view, integrating innovative, multidisciplinary lithic analyses with spatial patterning from surface scatters and geomorphology. This will highlight the latent potential of arid environments for a broader and more grounded understanding of early hominin behaviour and work towards developing new methods for providing chronological control.
Methods for survey, excavation and analysis of arid environment landscape archaeology have been outlined by Hardaker (2020) and adapted by Knight and Stratford (2020). The methodological techniques outlined here are based on recommended ‘stages of investigation’ appropriate for surface lithics scatters in an arid environment (Knight and Stratford 2020). First, we have identified the region of study (Gobabeb and surrounding region) based on preliminary knowledge of the ESA present there (Shackley 1980, 1982; Ted Marks pers. comm). Once the suitable site is identified a nonbiased sampling technique will be used to ensure an accurate representation of the technology. The methods for this procedure and subsequent analysis are outlined below:
Survey and Cataloging
An initial survey area in the western region of Namibia has been established by Hardaker (2011) as having a significant Earlier Stone Age artifact distribution. A re-examination of Namib IV, the Gobabeb region (Khommabes), the Tsauchab Plans and nearby ZR4 (Figure 1) will provide geographically distinct areas with artifacts. We will survey lithic scatters using a stratified unaligned sampling technique in order to eliminate surveyor bias (e.g. Knight and Stratford 2020, Table 1).
GPS and DGPS
Global Positioning System coordinates (GPS) points will be taken on each of the sites, ancient and modern resources, and raw materials sources. Using a Geographic Information System (GIS) such as ArcGIS, we will plot the data and digitally integrate it with satellite and high-resolution drone imagery. This will facilitate spatial analysis as well as providing an accurate record of the areas under investigation.
Blumenschine et al (2008) demonstrate a spatial relationship between the raw material source and Oldowan lithic reduction, specifically weight proportion decreases as the material is transported further from the source.Other work on surface and buried assemblages has shown an increase of retouch on artifacts found further away from their source location (Ricklis and Cox 1993; Dibble 1995). We plan to use a similar analysis as well. Clarkson’s (2013) scar density index (SDI) is a good measure of reduction intensity.
Portable X-Ray Fluorescence
Using a Bruker © pXRF, lithic scatter will nondestructively be tested for elemental composition. The pXRF will also be used on raw material sources. By testing the geochemical (elemental) composition of the lithics and incorporating ancient resource features (i.e. ancient water sources) and the source of the raw material, we will be able to further understand hominin movement on this arid landscape.
Scanning Electron Microscopy
Elemental and chemical signature of the artifacts will be assessed with the Scanning Electron Microscope (SEM). Using the SEM Hardaker (2011) demonstrated a measurable signature of elemental compositions which vary between cortical surfaces and non-cortical surfaces. As part of our design we will use these measurements to provide a new method of dating the chronological sequence of artifacts on the surface. The signatures of the various raw material sources will also be assessed to link the artifact with the source from which it was originally obtained.
Dating Artifact Patination and Desert Varnish
To assess intra-assemblage reuse we will sample the patination color differentiation between scars on single artifacts. The first field season will collect sample to assess which technique of varnish analysis is most appropriate. We believe that either a Mn/Fe analysis or a silica analysis will be most appropriate but hope the first field season will answer this question.
Many of the analyses and descriptions of the ESA of the Namib that are available used either out of date (Shackley 1982) or insufficient methods (Hardaker 2011; 2020), warranting the development of those outlined here. In conjunction with one another, the outlined methodology of this project will firmly establish an understanding of the ESA via contemporary analytical standards. Only then will the full range of hominin mobility in Southern Africa, including marginalized environments, be realized.
Educational Outreach and Opportunity
Our team is committed to increasing the diversity in palaeosciences. As such, upon successful permitting, we will be reaching out to UNAM to seek a qualified student or graduate student to participate in the fieldwork. It is our hope to facilitate a long-term relationship that would help provide additional opportunities to the individual to be part of analytical work and publication. In addition, we hope to give public lectures during our stay. Upon successful permitting, we will be contacting a local high school to reach out about speaking on heritage and the value of protecting Namibia’s important heritage.
DatesIf the permit is successful, we request that is it valid for 24 months to allow for multiple field seasons during the winter months.
We have applied to two sources of funding and believe this project is a strong candidate for both. We do have contingency plans in the case of funding being unsuccessful, but we do not foresee this currently.