The 'Lindholme Advance' and the extent of the Last Glacial Maximum in the Vale of York

The limits of the glacier that occupied the southwest part of the southern Vale of York at the Last Glacial Maximum are defined in relation to recent temporary exposures at Lindholme and previous regional mapping by Geoff Gaunt. Erratic content of associated diamicts indicates sources in the Yorkshire Dales, over Stainmore and along the Permo-Triassic outcrops on the west side of the Vale of York. The advance is dated to an episode associated with a high level of pro-glacial Lake Humber within the Last Glacial Maximum. Lidar imagery suggests that the northeastern ice limit is concealed beneath later alluvium of the rivers Ouse and Trent

Nothing Lasts Forever: Environmental Discourses on the Collapse of Past Societies

The study of the collapse of past societies raises many questions for the theory and practice of archaeology. Interest in collapse extends as well into the natural sciences and environmental and sustainability policy. Despite a range of approaches to collapse, the predominant paradigm is environmental collapse, which I argue obscures recognition of the dynamic role of social processes that lie at the heart of human communities. These environmental discourses, together with confusion over terminology and the concepts of collapse, have created widespread aporia about collapse and resulted in the creation of mixed messages about complex historical and social processes

Transcriptomics of the Bed Bug (Cimex lectularius)

BACKGROUND: Bed bugs (Cimex lectularius) are blood-feeding insects poised to become one of the major pests in households throughout the United States. Resistance of C. lectularius to insecticides/pesticides is one factor thought to be involved in its sudden resurgence. Despite its high-impact status, scant knowledge exists at the genomic level for C. lectularius. Hence, we subjected the C. lectularius transcriptome to 454 pyrosequencing in order to identify potential genes involved in pesticide resistance. METHODOLOGY AND PRINCIPAL FINDINGS: Using 454 pyrosequencing, we obtained a total of 216,419 reads with 79,596,412 bp, which were assembled into 35,646 expressed sequence tags (3902 contigs and 31744 singletons). Nearly 85.9% of the C. lectularius sequences showed similarity to insect sequences, but 44.8% of the deduced proteins of C. lectularius did not show similarity with sequences in the GenBank non-redundant database. KEGG analysis revealed putative members of several detoxification pathways involved in pesticide resistance. Lamprin domains, Protein Kinase domains, Protein Tyrosine Kinase domains and cytochrome P450 domains were among the top Pfam domains predicted for the C. lectularius sequences. An initial assessment of putative defense genes, including a cytochrome P450 and a glutathione-S-transferase (GST), revealed high transcript levels for the cytochrome P450 (CYP9) in pesticide-exposed versus pesticide-susceptible C. lectularius populations. A significant number of single nucleotide polymorphisms (296) and microsatellite loci (370) were predicted in the C. lectularius sequences. Furthermore, 59 putative sequences of Wolbachia were retrieved from the database. CONCLUSIONS: To our knowledge this is the first study to elucidate the genetic makeup of C. lectularius. This pyrosequencing effort provides clues to the identification of potential detoxification genes involved in pesticide resistance of C. lectularius and lays the foundation for future functional genomics studies

Ancient DNA preservation, genetic diversity and biogeography: A study of houseflies from Roman Qasr Ibrim, lower Nubia, Egypt

The optimal preservation of many Egyptian archaeological sites provides unique opportunities in the research into the evolution of synanthropic species, wild animals or plants, which benefit from close association with man-made human habitats. In this study we extracted and analysed ancient mitochondrial DNA (mtDNA) from three synanthropic insect species, two storage pests, Sitophilus granarius (Coleoptera: Curculionidae) (N = 8) and Trogoderma granarium (Coleoptera: Dermestidae) (N = 14), and the housefly Musca domestica (Diptera: Muscidae), (N = 14), from Roman Qasr Ibrim, an Egyptian frontier site located in lower Nubia. The impact of different experimental variables on ancient DNA recovery was also evaluated, confirming that it is possible to extract endogenous ancient DNA from desiccated specimens while preserving the insect exoskeleton. A phylogenetic comparison of the Qasr Ibrim housefly mtDNA-COI (COI) with modern housefly sequences, revealed that they were genetically similar to modern Egyptian, Near Eastern, Indian, Japanese, and US/Canadian populations. As the now cosmopolitan houseflies were transported by human populations alongside domestic animals and crops and may have aided the spread of disease, these findings provide important information for these processes. While limited by the resolution of the comparative databases, our research suggests the existence of biological invasions and links across the Red Sea from Egypt to the Arabian Peninsula, and exchanges between India and Egypt. We demonstrate the great potential of fossil insect aDNA for reconstructing biogeographic and diachronic species distribution and for better understanding past environments

Ancient pests: The season of the Santorini Minoan volcanic eruption and a date from insect chitin

Attributing a season and a date to the volcanic eruption of Santorini in the Aegean has become possible by using preserved remains of the bean weevil, Bruchus rufipes, pests of pulses, from the storage jars of the West House, in the Bronze Age settlement at Akrotiri. We have applied an improved pre-treatment methodology for dating the charred insects, and this provides a date of 1744-1538 BC. This date is within the range of others obtained from pulses from the same context and confirms the utility of chitin as a dating material. Based on the nature of the insect material and the life cycle of the species involved, we argue for a summer eruption, which took place after harvest, shortly after this material was transported into the West House storeroom. © 2013 Springer-Verlag Berlin Heidelberg

The Norse landnám on the North Atlantic islands: an environmental impact assessment

The Norse colonisation or landnám of the North Atlantic islands of the Faroes, Iceland and Greenland, from the ninth century AD onwards, provides opportunities to examine human environmental impacts on ‘pristine’ landscapes of an environmental gradient from warmer more maritime conditions in the east to colder more continental conditions in the west. In this paper we consider key environmental contrasts across the Atlantic and initial settlement impacts on the biota and landscape. The modes of origin of the biota, which resulted in boreo-temperate affinities, a lack of endemic species, limited diversity and no grazing mammals on the Faroes or Iceland, are crucial in determining environmental sensitivity to human impact and in particular the impact of introduced domestic animals. Gathering new data, understanding their geographical patterns and changes through time is seen as crucial when tackling fundamental questions about human interactions with environment that are relevant to both understanding the past and planning for the future

Last glacial dynamics of the Vale of York and North Sea lobes of the British and Irish Ice Sheet

During the Last Glacial Maximum, the Vale of York and North Sea lobes of the British and Irish Ice Sheet extended to within 10 km of each other, impounding a series of pro-glacial lakes. Such an interplay of ice lobes provides a useful analogue for elsewhere in the North Sea basin. This paper focusses on reconstructing the Vale of York and North Sea Ice lobes using a regional suite of 25 luminescence ages in combination with stratigraphical and geomorphic evidence. Results extend and revise the chronology of the Dimlington LGM typesite, showing that the North Sea Ice lobe advanced between 20.9–17.1 ka and 17.1–15.1 ka before present. Initially this lobe impounded a proto Lake Humber which likely covered parts of Holderness as well as the southern part of the Vale of York. Later stages of Lake Humber within the Vale of York show continued blockage of the Humber Gap by the North Sea Ice lobe. The Vale of York Ice extended briefly at ∼18.7 ± 0.63 ka across Lake Humber into South Yorkshire and North Lincolnshire before retreating to and forming the Escrick and York moraines. Both glacier lobes appear to have been short-lived, comprising relatively dynamic ice, especially when moving into areas of deformable lacustrine sediments, which allowed them to rapidly advance and over-extend their margins due to low basal shear stress. Topographic control of the extent and spatial positioning of both Ice lobes also appears to have been significant