J Archaeol Sci 33 (10)

The paper examines the contradiction that, although fully natural interglacial and Holocene `waterlogged' deposits assumed to have formed in woodland generally contain abundant macrofossils of both plants and insects indicative of trees, British archaeological deposits rich in macrofossil remains of trees often lack, or contain very few, tree-associated insects. Assemblages of insect (Coleoptera and Hemiptera) remains from a range of modern deposits with various spatial relationships to woodland and trees were analysed. The proportions of tree-associated insects varied greatly. There was a general trend from higher values in woodland and near to isolated trees of species supporting a rich insect fauna, to low or zero values where there were no trees. However, low values sometimes occurred in woods or near trees, so that rarity of tree-associated insects in archaeological deposits does not always carry the implication of a treeless environment. Further investigation is suggested, with emphasis on the importance of identifying isolated trees, scrub and hedges as a resource for humans and wildlife in the past.

The paper discusses fully submerged shipwreck sites as open systems, in which material (sediment, water, organic and inorganic objects) and energy (wave, tidal, storm) are exchanged across system boundaries, and formation processes are driven by some combination of chemical, biological and physical processes, with physical processes dominant in initial phases of site formation. It is argued that scouring and associated depositional patterns that form in response to hydrodynamic forcing are commonly the dominant physical processes acting at shipwreck sites. Scour is initiated by the introduction of a shipwreck to the seafloor, leading to increases in flow velocity and turbulent intensity around the structure. Near-field and far-field scour pits form at wreck sites due to the interaction of horseshoe and lee wake vortices with the mobile substrate. The morphology of resultant scour signatures is controlled by the orientation of the wreck structure in relation to the prevailing hydrodynamic regime, the morphology and size of the wreck and individual site components, the hydrodynamic regime (currents, waves or combined waves and currents), bathymetry and the geology of the site (seafloor and sub-surface conditions). Individual objects or artefacts may act as nuclei to promote scour at a local scale. Under high-energy conditions, groups of artefacts and/or disarticulated structural components emanating from a wreck may compound natural scour processes by rolling or sliding. It is suggested that, under suitable environmental conditions, wreck-associated scour features can be preserved in the sedimentary record.

Assemblages of insects, mainly beetles (Coleoptera) from nine archaeological occupation sites in Northern England and one in Northern Ireland have been analysed statistically (principally using Spearman's rank-order correlation between pairs of species) in order to identify associations of taxa. Some sites gave strong and fairly discrete groupings, which could be related to individual insect habitats, or spatially or successionally related habitats, or to taphonomic pathways. Where less sharp groupings were identified, they included elements from those seen repeatedly elsewhere and appeared to reflect the character of the site, for example juxtaposition of habitats (as in stable manure), very uniform conditions, or rarity of insect habitats. It is concluded that, with suitable caution, analyses of this kind represent a transferable methodology of great value in obtaining archaeologically relevant information, as well as in improving understanding of the way insects adapted to artificial habitats in the past. Includes

numbers of records of the taxa used in the analyses, by site