A Landscape Approach to Archaeological Variability at the Acheulian to Middle Stone Age Transition in the Kapthurin Formation, Kenya

在美国国家科学基金会的支持下，由Sally McBrearty博士带领的考古学家和地质学家组成的团队将在肯尼亚的Baringo地区进行为期三个季节的实地考察。该小组将调查大约30万年前，随着智人在东非大裂谷的出现，中更新世的土地利用模式是如何变化的。他们将把重点放在Kapthurin组的三个地层间隔上，在这些地层中，含有被认为是直立人制造的阿舍利文物的遗址，与含有被认为是智人制造的中石器时代文物的遗址处于层间。利用激光过境地质填图重建古地形，利用GIS软件重建各目标区间的三维模型。通过研究哺乳动物和植物化石，以及土壤化石和牙齿化石的稳定碳氧同位素，将记录古代植物和动物群落。在每个地层间隔的两个地点进行地面采集、试验沟槽和水平挖掘，将为早期人类的行为提供石器工具和被早期原始人加工为食物的化石骨的证据。这些行为痕迹与地形特征和植物群落的关联模式将在每个目标区间内寻求。早期智人的土地利用模式发生了变化，反映出更强的认知能力、技术能力和地理范围，这可以从解剖学和考古学的角度进行预测，但迄今为止的证据来自广泛分散的地点，而且没有很好的确定时间。Kapthurin组局限于单一沉积盆地，采用40Ar/39Ar定年方法标定了待研究层段的年龄。将比较在三个地层间隔中发现的任何土地利用模式，以评估随时间变化的性质和速度。麦克布里蒂博士和她的合作者将专注于五个问题：1)在阿赫利时代和中石器时代之间，土地利用模式是否存在可检测到的变化？2)中石器时代的原始人是否比阿舍利时代的原始人使用更广泛的微栖息地，比如高地和远端洪泛平原，以及溪流和湖边环境？3)中石器时代的原始人是否能够比阿舍利时代的原始人更远离水源或石器制造原料？4)阿舍利时代或中石器时代的工具制造者是否设计了特定的工具来开发特定的栖息地？5)与中石器时代的猎人相比，阿舍利猎人的能力如何？这项研究很重要，因为它将阐明最早智人成员的行为本质，并阐明导致我们物种起源的一些过程。

With the support of the National Science Foundation a team of archaeologists and geologists led by Dr. Sally McBrearty will carry out three seasons of field work in the Baringo region of Kenya. The team will investigate how Middle Pleistocene landuse patterns changed with the appearance of Homo sapiens in the East African Rift Valley about 300,000 years ago. They will focus upon three stratigraphic intervals within the Kapthurin Formation, where sites containing Acheulian artifacts, thought to have been made by Homo erectus, are interstratified with those containing Middle Stone Age artifacts, thought to have been made by Homo sapiens. The ancient topography will be reconstructed by geological mapping with laser transit, and a three-dimensional model of each target interval will be reconstructed using GIS software. The ancient plant and animal communities will be documented through the study of mammalian and plant fossils, as well as fossil soil and fossil tooth stable carbon and oxygen isotopes. Surface collection, trial trenches, and horizontal excavation at two sites per stratigraphic interval will provide evidence for early human behavior in the form of stone tools and fossil bone which has been processed for food by early hominids. Patterns of association of these behavioral traces of with topographic features and plant communities will be sought for each target interval. A change in landuse patterns with early Homo sapiens, reflecting greater cognitive abilities, technical competence, and geographic range, can be predicted on anatomical and archaeological grounds, but the evidence to date has been drawn from widely dispersed sites which are not well dated. The Kapthurin Formation is confined to a single depositional basin, and the ages of the stratigraphic intervals to be studied are well calibrated by the 40Ar/39Ar dating method. Any landuse patterns detected in the three stratigraphic intervals will be compared to assess the nature and tempo of change through time. Dr. McBrearty and her collaborators will focus on five questions: 1) Is there a detectable change in landuse patterns between the Acheulian and Middle Stone Age? 2) Did Middle Stone Age hominids use a broader array of microhabitats than Acheulian hominids, such as uplands and distal floodplains, in addition to stream and lakeside settings? 3) Were Middle Stone Age hominids able to range further from sources of water or raw material for stone tool making than Acheulian hominids? 4) Were either Acheulian or Middle Stone Age tool makers designing specific implements to exploit particular habitats? 5) How does the competence of Acheulian hunters compare with hunters of the Middle Stone Age? This research is important because it will illustrate the nature of the behavior of the earliest members of Homo sapiens and illuminate some of the processes leading to the origin of our species.