Any current definition of Earth System Science sees human activities as integral to the way in which the Earth System functions. People are now key players in the system, not passive recipients of the consequences of natural processes. The emerging consensus is that this applies, above all, to what has become characterized as the Anthropocene (Crutzen and Stoermer 2001) - the past two to three centuries, and, most significantly, the past 60 years (Steffen et al. 2003). Human impact on the environment, however, has a much longer history than this. What do we know and what more do we need to know about this longer term history? It is especially appropriate to address these questions in the context of the HOLIVAR (Holocene Climate Variability) initiative, linked as it is to the PAGES (Past Global Changes) PEP (Pole-Equator-Pole) III Transect (Battarbee et al. 2004), for some of the clearest evidence for past human impacts has come through research in Europe. Moreover, as we turn southward from Europe to Africa, that continent includes some of the people most vulnerable to the combined effects of climate variability and human activities.

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