The distribution and abundance of plants and animals during the Quaternary is of great interest in the understanding of the pattern for any particular species. In our case it is fundamental to understanding the way in which humans were distributed at different times during the Quaternary.

It is important to start our discussion at the macro-ecological scale. The broad biogeographic picture will give us important insights at the scale which is most relevant to our study. We will zoom into lower spatio-temporal scales in later chapters where it is relevant to the discussion. I will not spend time discussing well-established biogeographic patterns that I do not regard to be especially relevant to this book. I am more concerned with the distribution and shifts in distribution of environments that would have influenced human distribution and I will confine my discussion largely to the Eurasian and African land masses which is where the main events took place.

Vegetation structure

In this book I will place particular emphasis on vegetation structure, that is the three-dimensional arrangement of plants in space. The reason for this is that I consider that vegetation structure will have played a major role in the distribution of humans, as it does for most animals (Bell et al., 1991). Vegetation structure would have been particularly important in determining the types of potential prey available to humans and also in making prey visible and accessible.