Internet Archaeology 11: Ray & Adams Introduction.

1.0: Introduction

In archaeology and anthropology there is now a great deal of interest in the global climate fluctuations which have occurred repeatedly over the last 2-4 million years, during the Quaternary period. In part, this interest reflects the hope that better understanding of the Earth's recent past will allow improved prediction of future human effects on the environment. There is also a great deal of purely academic curiosity amongst archaeologists, anthropologists, ecologists, climatologists, and biogeochemists about the ways that the global environment has changed during the recent past, and the way in which each aspect of the global system has interacted with others. In archaeology, it is becoming increasingly clear that it is necessary to include the study of the shifting climatic and ecological background if an understanding of the behaviour and movements of peoples is to be reached. A great deal of interesting work has begun to appear as a result of taking an 'environmental' approach to human evolution and history (e.g. work by Ortloff and Kolata 1993; Wright 1993; Steele et al.1998; Anderson and Gillam 2000). Yet archaeologists and anthropologists, together with other Quaternary scientists, have difficulty obtaining the basic background information which exists in such a scattered form throughout the literature.

To make this task easier, and to aid understanding of how the Earth has changed since the peak of the last ice age (and the main sources of evidence for deducing these changes) around 18,000 radiocarbon years ago (or around 20,000-21,000 calendar years ago, allowing for the relative changes in 14C abundance), we present here a set of maps depicting the world's changing vegetation cover on a region-by-region basis. The maps were compiled by us, based on modification and improvement of the earlier Quaternary Environments Network (QEN) vegetation maps (Adams and Faure 1997).

There remains considerable room for disagreement about the history of certain parts of the late Quaternary world. The maps presented here certainly cannot be regarded as the definitive work on the subject: instead they represent a necessary step in the process of assembling data and opinion from the many scientists who work on vegetation reconstruction. Anyone using these maps is urged to consult the description of methods presented in the following pages in order to get some idea of the uncertainties that remain. Certain aspects of the maps remain to some extent controversial and they represent the views of the authors, not necessarily those of consulted individuals (although we have encountered broad support, and have tried to consider the advice of every participant). Some marked disagreements in approach and overall conclusions were evident amongst the scientists who contributed to the Network, but despite a few wayward voices, a striking overall consensus was present.

As well as providing a ready source of information for archaeologists, we also hope that our maps may prove useful to those within the Quaternary palaeoecology community. As a coherent map of global vegetation for a particular interval in the past, it should act as a baseline for further work in vegetation reconstruction - even if only as a target for criticism.