Climatic change and reconstruction

The Holocene has been characterised by changing climate conditions. The lon g-term trends are reflected by palaeoclimate simulations made using atmosph eric general circulation models. Palaeoclimate reconstructions made from a variety of fossil remains and other proxies reveal both finer-scale spatial patterns than are seen in these simulations and also shorter time scale va riability superimposed upon the overall Holocene trends. It is important to acknowledge both the spatial heterogeneity of palaeoclimate changes and th e variability of climate at all time scales. Organisms respond to climate c hanges both by migration and by adaptive evolution. It is probable that pre industrial humans responded similarly, although the development of an oral tradition and of written records may have extended the time scale of the co llective experience and thus the characteristic time scale of changes that would elicit such responses. High temporal-and spatial-resolution collabora tive work by archaeologists and palaeoecologists is required to address the se issues critically.