This volume presents the results of an analysis of microscopic wear traces on chert artefacts from a variety of pre-ceramic period sites in Colombia. Nieuwenhuis uses wear trace analysis to explore the relationship between Abrian and Tequendamian artefacts, and the different systems of tool production and use. Focusing on material from sites in the high plain of Bogota and the middle Magdalena Valley, Nieuwenhuis extends the study to consider the complex relationships between tool use and changes in climate and environment. The distinction between Tequendamian and Abrian artefact classes has long been related to the climatic, vegetational and faunal changes of the Pleistocene/Holocene transition. Tequendamian tools were thought to belong to late Pleistocene hunters of large game in open landscapes, but were gradually replaced by Abrian tools at the onset of the Holocene; Abrian tools were considered a specialised adaptation to the changing environment, and were used by Holocene foragers exploiting the resources of the tropical rainforest. In the past decade, however, the strict chronological division between the two classes has become blurred.
Nieuwenhuis argues that the Abrian tools represent a simple, multifunctional, versatile toolkit, while Tequendamian tools did not have an explicit specialised function, but served various domestic tasks, and were used for some sort of status-related exchange.