Migration distance rather than migration rate explains genetic diversity in human patrilocal groups

In patrilocal groups, females preferentially move to join their mate’s paternal relatives. The gender‐biased gene flow generated by this cultural practice is expected to affect genetic diversity across human populations. Greater female than male migration is predicted to result in a larger decrease in between‐group differentiation for mitochondrial DNA (mtDNA) than for the non‐recombining part of the Y chromosome (NRY). We address the question of how patrilocality affects the distribution of genetic variation in human populations controlling for confounding factors such as ethno‐linguistic heterogeneity and geographic distance which possibly explain the contradictory results observed in previous studies. By combining genetic and bio‐demographic data from Lesotho and Spain, we show that preferential female migration over short distances appears to minimize the impact of a generally higher female migration rate in patrilocal communities, suggesting patrilocality might influence genetic variation only at short ranges.     

Rapid recovery of mammal fauna in the central Kimberley,northern Australia,following the removal of introduced herbivores

Australia has lost more native mammal species than any other country in the past two centuries, and this record of loss looks likely to worsen over the next few decades. Small‐ to medium‐sized mammals are declining in both distribution and density across large tracts of northern Australia's tropical savannas, including within protected areas. The most likely causes are a combination of changed fire patterns, the impacts of introduced herbivores and predation by feral cats. Here, in contrast to the prevailing trend across northern Australia, we report the recovery of native mammals in response to a large‐scale (>40 000 ha) destocking experiment carried out at Mornington Wildlife Sanctuary in the central Kimberley, north‐west Australia. Following the removal of introduced herbivores from 2004, the species richness and abundance of small native rodents and dasyurids increased significantly across all sampled habitats over the next 3 years. We discuss the implications of these results for guiding land management and applied research to help to reduce the impending risk of mammalian extinctions in northern Australia.     

The distribution and environmental state of vegetated islands within human‐impacted European rivers

1. Vegetated islands within river corridors are pivotal landscape features and are among the first to disappear as a consequence of flow regulation and channelisation. However, how vegetated islands vary along human‐impacted rivers is poorly understood. 2. We carried out a detailed analysis of the contemporary distribution, diversity and environmental state of vegetated islands within 12 human‐impacted European rivers, using 75 Landsat 7 ETM+ satellite images (1999–2002), historical maps, DEM data and landscape metrics. We tested whether channel fragmentation, catchment land use and the environmental state of fringing floodplains determine the spatial patterns of the islands. We also analysed the historical change of islands within selected sections of the Upper Danube, Upper Rhine and Olt rivers. 3. We identified 2771 islands in the contemporary landscape, varying from 0.06 to 9828 ha. Islands covered up to 21% of the active channel area and contributed up to 32% of the total riparian ecotone length. Island density ranged from 0.06 islands per river‐km (River Sava) to 1.6 islands per river‐km (River Tagliamento). River regulation has led to a marked loss of island density: 94% in the Upper Danube, 93% in the Upper Rhine, and 69% in the Olt. The environmental state of the islands was significantly less altered by human activity than of their fringing floodplains; 93.4% of the vegetated islands exhibited a near‐natural state, while 86% of the fringing floodplains were expansively converted to agricultural and urban land uses. 4. Our results highlight the ubiquitous presence of vegetated islands, their sensitivity to river regulation and their pivotal role for the future restoration and management of river corridors.     

Differential responses of UK upland plants to nitrogen deposition

Native upland species, Nardus stricta , Eriophorum vaginatum , Erica cinerea and Vaccinium vitis-idaea were given 3 or 60 kg N ha⁻¹ yr⁻¹, over 2 yr, applied as a mist (NH₄NO₃). The high N treatment increased above-ground biomass in all four species, but only significantly in E. cinerea , E. vaginatum and N. stricta . Biomass increases in E. vaginatum and N. stricta resulted from enhanced tiller production rather than shoot elongation. Root growth increased in N. stricta , so that root:shoot ratio in this species was unchanged by N. Root growth in E. vaginatum , E. cinerea and V. vitis-idaea did not respond to N and their root:shoot ratios decreased. Tissue N concentrations increased in both shoots and roots of all species in response to N. The accumulated foliar N did not increase the proportion of N allocated to Rubisco and the photosynthetic capacities of N. stricta , E. vaginatum and V. vitis-idaea were unchanged. Thus growth responses to N were due to altered allocation rather than increased rate of photosynthesis per unit leaf area. The high N treatment increased flower production significantly in E. cinerea but not in the other species. Although in this experiment dwarf shrubs were more responsive than graminoids to N, in the field at current N inputs the enhanced tillering of the graminoids may be more competitively advantageous, especially where gaps develop in the canopy. Thus increasing N deposition may lead to increased grassiness of upland heath, and in particular, a spread of N. stricta .     

Persistence and stability of macroinvertebrate communities in streams of Denali National Park, Alaska: implications for biological monitoring

1. Macroinvertebrate communities were studied from 1994 to 2001/2002 (except 1997) in six streams in Denali National Park, interior Alaska. All six streams were potential reference streams with no known impairment. 2. Abundance of individual taxa varied markedly from year to year. Overall, abundance decreased over the study period, particularly with respect to mayflies. Stonefly taxa showed lower persistence and were sometimes absent from a stream in any particular year. 3. Mean community persistence for the six streams, as measured by Jaccard's similarity coefficients between years, varied from 0.48 in the year pair 1999–2000 to 0.78 in 1998–99. Tattler Creek (a small stable stream) supported the most persistent macroinvertebrate community and Highway Pass Creek (a small, unstable creek) the least. Mean community persistence showed a significant relationship with mean winter snowfall (November to March) for the six streams. 4. The highest community compositional stability was found in Tattler Creek and the lowest in Highway Pass Creek, but stability varied markedly over time for the six streams, peaking in 1994–95 and reaching a minimum in 2000–01. Compositional stability was significantly related to the Pfankuch Index of channel stability. 5. The composition metrics % Chironomidae, % dominant taxa, %EPT, % Ephemeroptera and % Plecoptera, employed as part of the Alaska Stream Condition Index, varied over almost their entire range in these pristine streams across the 9 years of the study. 6. This study demonstrates the wide range of natural variation that occurs in benthic macroinvertebrate communities in these pristine central Alaskan streams, potentially limiting the applicability of composition metrics for the biological monitoring of water quality in these systems.     

The spatial pattern of soil-dwelling termites in primary and logged forest in Sabah, Malaysia

Abstract.  1. Primary and logged lowland dipterocarp forest sites were sampled for subterranean termites using soil pits located on a grid system in order to detect any patchiness in their distribution.
2. A spatial pattern in termite distributions was observed in the primary and logged sites, but the response differed between soil-feeding and non-soil-feeding termites.
3. Spatial analysis showed that soil-feeding termites were homogeneously distributed in the primary forest but significantly aggregated in the logged forest. This pattern was reversed for non-soil-feeding termites and may result from differences in resource provisioning between the two sites.
4. Gaps in termite distribution comprised a greater area than patches for both feeding groups and sites, but gaps dominated the logged site.
5. A significant association between soil-feeding and non-soil-feeding termite distributions occurred at both sites. This arose from an association between patches in the primary forest and between gaps in the logged forest.
6. Termite spatial pattern was optimally observed at a minimum extent of 64 m and lag of 2 m.
7. The spatially explicit SADIE (Spatial Analysis by Distances IndicEs) analyses were more successful than (non-spatially explicit) multivariate analysis (Canonical Correspondence Analysis) at detecting associations between termite spatial distributions and that of other biotic and abiotic variables.     

Hidden diversity and endemism on seamounts: focus on poorly dispersive neogastropods

The seamounts chain offers a set of fragmented habitats in which species with poor dispersive ability may undergo divergence in allopatry. Such a scenario may explain the endemism often described on seamounts. In gastropods, it is possible to infer the mode of development of a species from the morphology of its larval shell. Accordingly, we examine the population genetics of several caenogastropods from the Norfolk and Lord Howe seamounts (south‐west Pacific) with contrasting modes of larval development. A prerequisite to our study was to clarify the taxonomic framework. The species delimitation was ruled using an integrative approach, based on both morphological and molecular evidence. Molecular data indicate an unexpected taxonomic diversity within the existing species names. Both the clarification of the taxonomic framework and the importance of the sampling effort allow us to confidently detect cryptic diversity and micro‐endemism. These results are discussed in relation to the dispersive capacities of the organisms. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 420–438.     

Costs and benefits of cervical screening IV: valuation by women of the cervical screening programme

OBJECTIVES: To assess the value of the cervical smear test to women, taking account of the positive and negative aspects of the cervical screening service. DESIGN: A postal survey. SETTING: Tayside Health Board region of Scotland. PARTICIPANTS: A sample of 2000 women aged 20-59. MAIN OUTCOME MEASURES: Maximum willingness to pay (WTP) for a cervical smear test. RESULTS: Women were prepared to pay 50.20 British pounds per smear on a 3-yearly basis. Willingness to pay was positively related to income, but unrelated to age and whether or not the respondent had previously had a smear. CONCLUSIONS: Previous studies have estimated the cost per screen or cost per life year saved by cervical screening. This study used the economic instrument of WTP to take account of other potential (dis)benefits to women. The value women place on having a smear was more than the cost to the National Health Service (NHS) of providing the service. The output of a WTP study is potentially useful at the policy level. Future work should explore both the value of alternative approaches to cervical screening, and the value of competing health care interventions.     

Women's Health in Post-Soviet Russia: The Politics of Intervention

Women's Health in Post-Soviet Russia: The Politics of Intervention . Michele Rivkin-Fish. Indianapolis: University of Indiana Press, 2006. 253 pp.     

Fuel-Reduction Treatment Effects on Avian Community Structure and Diversity

Abstract: We assessed responses of the breeding bird community to mechanical thinning and prescribed surface fire, alone and in combination, between 2000 and 2006 in ponderosa pine (Pinus ponderosa) forests in northern Arizona, USA. Fuel-reduction treatments did not affect species richness or evenness, and effects on density of 5 commonly detected species varied among species. Populations of some species, such as the western bluebird (Sialia mexicana), increased following burning treatments, whereas others, such as the mountain chickadee (Poecile gambeli), decreased in response to thinning treatments. Our results also identified a temporal response component, where avian community composition and structure changed synchronously on all treatments over time. Given the modest effects these small-scale fuel-reduction treatments had on avian composition and the specific density responses of particular species, our results suggest that land managers should consider implementing prescribed surface fire after thinning projects, where appropriate.