Bryophyte diversity and community structure on thatched roofs of the Holnicote Estate, Somerset, U.K.

We investigated patterns of bryophyte species richness and community structure, and their relation to roof variables, on thatched roofs of the Holnicote Estate, South Somerset. Thirty-two bryophyte species were recorded from 28 sampled roofs, including the globally rare and endangered thatch moss, Leptodontium gemmascens. Multiple regression analyses revealed that thatch age has a highly significant positive effect on the number of species present, accounting for nearly half the observed variation in species richness after removal of outliers. Aspect has a slight and marginally significant effect on species diversity (accounting for an additional 6% of variation), with north-facing samples having slightly more species. Age also has a significant impact on total bryophyte cover after removal of outlying observations. TWINSPAN analysis of bryophyte cover data suggests the existence of at least five discrete communities. Simple Discriminant Analyses indicate that these communities occupy different ecological subspaces as defined by the measured roof variables, with pitch, aspect and thatch age emerging as especially significant attributes. Contingency Analysis indicates that some communities are disfavoured by water reed as compared to wheat straw. The findings are significant for understanding the structure of bryophyte communities, for evaluating the effect of bryophyte cover on thatch performance, and for conservation of thatch communities, especially those harbouring rare species.

High-throughput monitoring of wild bee diversity and abundance via mitogenomics

1. Bee populations and other pollinators face multiple, synergistically acting threats, which have led to population declines, loss of local species richness and pollination services, and extinctions. However, our understanding of the degree, distribution and causes of declines is patchy, in part due to inadequate monitoring systems, with the challenge of taxonomic identification posing a major logistical barrier. Pollinator conservation would benefit from a high-throughput identification pipeline. 2. We show that the metagenomic mining and resequencing of mitochondrial genomes (mitogenomics) can be applied successfully to bulk samples of wild bees. We assembled the mitogenomes of 48 UK bee species and then shotgun-sequenced total DNA extracted from 204 whole bees that had been collected in 10 pan-trap samples from farms in England and been identified morphologically to 33 species. Each sample data set was mapped against the 48 reference mitogenomes. 3. The morphological and mitogenomic data sets were highly congruent. Out of 63 total species detections in the morphological data set, the mitogenomic data set made 59 correct detections (93�7% detection rate) and detected six more species (putative false positives). Direct inspection and an analysis with species-specific primers suggested that these putative false positives were most likely due to incorrect morphological IDs. Read frequency significantly predicted species biomass frequency (R2 = 24�9%). Species lists, biomass frequencies, extrapolated species richness and community structure were recovered with less error than in a metabarcoding pipeline. 4. Mitogenomics automates the onerous task of taxonomic identification, even for cryptic species, allowing the tracking of changes in species richness and istributions. A mitogenomic pipeline should thus be able to contain costs, maintain consistently high-quality data over long time series, incorporate retrospective taxonomic revisions and provide an auditable evidence trail. Mitogenomic data sets also provide estimates of species counts within samples and thus have potential for tracking population trajectories.

Migration and diversity in Roman Britain: a multidisciplinary approach to immigrants in Roman York, England

Previous anthropological investigations at Trentholme Drive, in Roman York identified an unusual amount of cranial variation amongst the inhabitants, with some individuals suggested as having originated from the Middle East or North Africa. The current study investigates the validity of this assessment using modern anthropological methods to assess cranial variation in two groups: The Railway and Trentholme Drive. Strontium and oxygen isotope evidence derived from the dentition of 43 of these individuals was combined with the craniometric data to provide information on possible levels of migration and the range of homelands that may be represented. The results of the craniometric analysis indicated that the majority of the York population had European origins, but that 11% of the Trentholme Drive and 12% of The Railway study samples were likely of African decent. Oxygen analysis identified four incomers, three from areas warmer than the UK and one from a cooler or more continental climate. Although based on a relatively small sample of the overall population at York, this multidisciplinary approach made it possible to identify incomers, both men and women, from across the Empire. Evidence for possible second generation migrants was also suggested. The results confirm the presence of a heterogeneous population resident in York and highlight the diversity, rather than the uniformity, of the population in Roman Britain. Am J Phys Anthropol 140:546-561, 2009. (C) 2009 Wiley-Liss, Inc

Diversity and difference in the everyday lives of Ugandan street children: The significance of age and gender for understanding the use of space

Childhood is characterised by diversity and difference across and within societies. Street children have a unique relationship to the urban environment evident through their use of the city. The everyday geographies that street children produce are diversified through the spaces they frequent and the activities they engage in. Drawing on a range of children-centred qualitative methods, this article focuses on street children's use of urban space in Kampala, Uganda. The article demonstrates the importance of considering variables such as gender and age in the analysis of street children's socio-spatial experiences, which, to date, have rarely been considered in other accounts of street children's lives. In addition the article highlights the need for also including street children's individuality and agency into understanding their use of space. The article concludes by arguing for policies to be sensitive to the diversity that characterises street children's lives and calls for a more nuanced approach where policies are designed to accommodate street children's age and gender differences, and their individual needs, interests and abilities.

Controls on development and diversity of Early Archean stromatolites

The ≈3,450-million-year-old Strelley Pool Formation in Western Australia contains a reef-like assembly of laminated sedimentary accretion structures (stromatolites) that have macroscale characteristics suggestive of biological influence. However, direct microscale evidence of biology—namely, organic microbial remains or biosedimentary fabrics—has to date eluded discovery in the extensively-recrystallized rocks. Recently-identified outcrops with relatively good textural preservation record microscale evidence of primary sedimentary processes, including some that indicate probable microbial mat formation. Furthermore, we find relict fabrics and organic layers that covary with stromatolite morphology, linking morphologic diversity to changes in sedimentation, seafloor mineral precipitation, and inferred microbial mat development. Thus, the most direct and compelling signatures of life in the Strelley Pool Formation are those observed at the microscopic scale. By examining spatiotemporal changes in microscale characteristics it is possible not only to recognize the presence of probable microbial mats during stromatolite development, but also to infer aspects of the biological inputs to stromatolite morphogenesis. The persistence of an inferred biological signal through changing environmental circumstances and stromatolite types indicates that benthic microbial populations adapted to shifting environmental conditions in early oceans.

Diet and diversity at later medieval Fishergate: The isotopic evidence

We present the results of stable carbon and nitrogen isotope analysis of bone collagen for 155 individuals buried at the Later Medieval (13th to early 16th century AD) Gilbertine priory of St. Andrew, Fishergate in the city of York (UK). The data show significant variation in the consumption of marine foods between males and females as well as between individuals buried in different areas of the priory. Specifically, individuals from the crossing of the church and the cloister garth had consumed significantly less marine protein than those from other locations. Isotope data for four individuals diagnosed with diffuse idiopathic skeletal hyperostosis (DISH) are consistent with a diet rich in animal protein. We also observe that isotopic signals of individuals with perimortem sharp force trauma are unusual in the context of the Fishergate dataset. We discuss possible explanations for these patterns and suggest that there may have been a specialist hospital or a local tradition of burying victims of violent conflict at the priory. The results demonstrate how the integration of archaeological, osteological, and isotopic data can provide novel information about Medieval burial and society.

Diversity and difference in the everyday lives of Ugandan street children: The significance of age and gender for understanding the use of space

Childhood is characterised by diversity and difference across and within societies. Street children have a unique relationship to the urban environment evident through their use of the city. The everyday geographies that street children produce are diversified through the spaces they frequent and the activities they engage in. Drawing on a range of children-centred qualitative methods, this article focuses on street children's use of urban space in Kampala, Uganda. The article demonstrates the importance of considering variables such as gender and age in the analysis of street children's socio-spatial experiences, which, to date, have rarely been considered in other accounts of street children's lives. In addition the article highlights the need for also including street children's individuality and agency into understanding their use of space. The article concludes by arguing for policies to be sensitive to the diversity that characterises street children's lives and calls for a more nuanced approach where policies are designed to accommodate street children's age and gender differences, and their individual needs, interests and abilities.

Evolution of functional diversity in the cupin superfamily

The cupin superfamily of proteins is among the most functionally diverse of any described to date. It was named on the basis of the conserved beta-barrel fold ('cupa' is the Latin term for a small barrel), and comprises both enzymatic and non-enzymatic members, which have either one or two cupin domains. Within the conserved tertiary structure, the variety of biochemical function is provided by minor variation of the residues in the active site and the identity of the bound metal ion. This review discusses the advantages of this particular scaffold and provides an evolutionary analysis of 18 different subclasses within the cupin superfamily.

Landscape context and habitat type as drivers of bee diversity in European annual crops

To better understand the dynamics of bee populations in crops, we assessed the effect of landscape context and habitat type on bee communities in annual entomophilous crops in Europe. We quantified bee communities in five pairs of crop-country: buckwheat in Poland, cantaloupe in France, field beans in the UK, spring oilseed rape in Sweden, and strawberries in Germany. For each country, 7-10 study fields were sampled over a gradient of increasing proportion of semi-natural habitats in the surrounding landscape. The CORINE land cover classification was used to characterize the landscape over a 3 km radius around each study field and we used multivariate and regression analyses to quantify the impact of landscape features on bee abundance and diversity at the sub-generic taxonomic level. Neither overall wild bee abundance nor diversity, taken as the number of sub-genera. was significantly affected by the proportion of semi-natural habitat. Therefore, we used the most precise level of the CORINE classification to examine the possible links between specific landscape features and wild bee communities. Bee community composition fell into three distinct groups across Europe: group I included Poland, Germany, and Sweden, group 2 the UK, and group 3 France. Among all three groups, wild bee abundance and sub-generic diversity were affected by 17 landscape elements including some semi-natural habitats (e.g., transitional wood land-shrub), some urban habitats (e.g., sport and leisure facilities) and some crop habitats (e.g., non-irrigated arable land). Some bee taxa were positively affected by urban habitats only, others by semi-natural habitats only, and others by a combination of semi-natural, urban and crop habitats. Bee sub-genera favoured by urban and crop habitats were more resistant to landscape change than those favoured only by semi-natural habitats. In agroecosystems, the agricultural intensification defined as the loss of semi-natural habitats does not necessarily cause a decline in evenness at the local level, but can change community composition towards a bee fauna dominated by common taxa. (C) 2009 Elsevier B.V. All rights reserved.

Hay strewing, brush harvesting of seed and soil disturbance as tools for the enhancement of botanical diversity in grasslands

Since the middle of the last century agricultural intensification within Europe has led to a drastic decline in the extent of botanically diverse grasslands. Whilst measures to enhance the diversity of agriculturally-improved grasslands are in place, success has often been limited. One of the primary factors limiting success is the paucity of sources of propagules of desirable species in the surrounding landscape. The restoration of two contrasting grassland types lowland hay meadow and chalk grassland) was examined using a replicated block experiment to assess the effectiveness of two methods of seed application (hay strewing and brush harvesting) and two methods of pre-treatment disturbance (power harrowing and turf stripping). The resulting changes in botanical composition were monitored for 4 years. Seed addition by both methods resulted in significant temporal trends in plant species composition and increases in plant species richness, which were further enhanced by disturbance. Power harrowing increased the effectiveness of the seed addition treatments at the lowland hay meadow site. At the chalk grassland site a more severe disturbance created by turf stripping was used and shown to be preferable. Whilst both hay strewing and brush harvesting increased plant species richness, hay strewing was more effective at creating a sward similar to that of the donor site. Soil disturbance and seed application rate at the recipient site and timing of the hay cut at the donor site are all factors to be considered prior to the commencement of restoration management. (c) 2006 Elsevier Ltd. All rights reserved.

Fragmentation or creative diversity? Options in the provision of land management advisory services

Rural land managers need access to sound advice and information to respond to pressures from environmental regulations, declining farm incomes, changing patterns in international trade and new institutional arrangements within the domestic food chain. Governments have cut back their provision of advisory services but need more than ever to influence land managers' decisions to achieve a growing array of policy objectives: The paper develops a conceptual framework for analysing advisory services and concludes, through a review of sixteen case studies, that the needs of both governments and land managers can be met by a diverse mixture of private and public sector provision. (C) 2003 Elsevier Ltd. All rights reserved.