Fossil insect remains as indicators of the primeval forest; a modern analogue approach.

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Native woodland is a scarce resource of high cultural, scientific and nature conservation importance throughout Europe. In a recently published hypothesis, a Danish woodland ecologist, Frans Vera, has argued that the current European management policy towards 'closed' canopy woodland is affecting the continued viability of specialised plants and animals of the forest. Many sites are highly valued for these specialised species. Vera argues that large herbivores played an important role in maintaining substantial open areas in the 'wildwood' of primeval Europe, so that the forest, far from being closed, was in fact quite open. This is contrast to the established thinking that the 'wildwood' was a closed canopy forest and so management of ancient woodland sites, which aims to maintain and/or restore sites to their natural ecological state, has been geared towards this assumption. The implications of Vera's argument are clear: if he is correct, we have been managing these precious sites (and their species) in an incorrect manner and are thus are danger of compromising their future. In order to establish whether the 'wildwood' was indeed closed or open, we can turn to the fossil record of plants and animals living at the time of the 'wildwood' to establish which of these two theories are broadly correct. Fossil beetles are very useful indicators of past environments and especially woodland environments. Previous work by the applicants has already established that beetles have considerable potential to establish whether Vera's ideas are borne out by the evidence, but we need to refine our understanding of what the fossil insect record means and how we interpret it. Essentially, we need to have a better idea of what 'open' or 'closed' woodland may look like in the fossil beetle record. In this project, we will collect recent fossil insect data from a range of ancient woodlands with different canopy structures (open, intermediate and closed) and well-recorded management systems, including grazing and mowing. The recent fossil data will be collected from sediment samples taken from the loose sediments at the base of small ponds in the middle of these ancient woodlands. A proportion of whatever insects are living in the woodlands will end up being deposited here. These recent fossils will probably represent individuals living in the vicinity over the last couple of decades. We will know from managment records that the areas sorrounding the ponds have not substantially changed over this period. By studying the recent fossil beetles and relating these statistically to the surrounding wooded areas, their canopy structure and management, we will be able to identify a fossil 'fingerprint' of what each site looks like in the fossil record. This will allow us to determine the broad characteristics of these types of woodlands which may be found in the fossil record. We have to study recent fossils rather than modern collected beetles as we are concerned with the interpretation of the fossil record, rather than the interpretation of the modern insect fauna. Of course, our study sites will not provide us with a complete range of potential types of woodlands which may have existed in the past, but they should allow us to separate 'open' from 'closed' canopy woodland and, possibly, establish the importance of management influences on their insect faunas. Finally, we will then collate and re-analyse published European fossil beetle data dating to c. 9,000-5,000 years ago and some selected earlier sites, in the light of refined understanding of beetle characteristics from forest environments. This will allow us to produce a more robust environmental reconstruction of native 'wildwood' and test whether the natural 'wildwood' was indeed closed or open canopy, providing contradictory or supporting evidence towards the landscape structure identified by Vera and its continued viability.