It has been suggested that we do not know within an order of magnitude the number of all species on Earth [May RM (1988) Science 241(4872):1441-1449]. Roughly 1.5 million valid species of all organisms have been named and described [Costello MJ, Wilson S, Houlding B (2012) Syst Biol 61(5):871-883]. Given Kingdom Animalia numerically dominates this list and virtually all terrestrial vertebrates have been described, the question of how many terrestrial species exist is all but reduced to one of how many arthropod species there are. With beetles alone accounting for about 40% of all described arthropod species, the truly pertinent question is how many beetle species exist. Here we present four new and independent estimates of beetle species richness, which produce a mean estimate of 1.5 million beetle species. We argue that the surprisingly narrow range (0.9-2.1 million) of these four autonomous estimates-derived from host-specificity relationships, ratios with other taxa, plant:beetle ratios, and a completely novel body-size approach-represents a major advance in honing in on the richness of this most significant taxon, and is thus of considerable importance to the debate on how many species exist. Using analogous approaches, we also produce independent estimates for all insects, mean: 5.5 million species (range 2.6-7.8 million), and for terrestrial arthropods, mean: 6.8 million species (range 5.9-7.8 million), which suggest that estimates for the world's insects and their relatives are narrowing considerably.biodiversity | body size | Coleoptera | species richness B eetles account for roughly 25% (350,000-400,000 species)(1) of all described species (∼1.5 million species), making this the most species-rich order known on Earth and supporting the philosopher Haldane's famous observation that God has "an inordinate fondness for beetles" (2, 3). Therefore, because this is a single lineage, an understanding of their global species richness, and that of the insects and other arthropods of which they form a part, is particularly important. There have been several reviews that discuss the merits of different estimates of the species richness for these taxa as well as of other organisms (1, 4-9), but none have been able to use these to derive mean estimates with some measure of error associated with these means. Here we compare global species estimates for beetles, insects, and terrestrial arthropods from eight different methods of estimation (here called methods 1-8). One of these (method 8) we introduce here, called the "body size and year of description" method, is based on the observed tendency for larger species of organisms to be described and named before smaller species, resulting in a decline in the mean body size of named species over time (10,11). We use data for beetles from the Natural History Museum (NHM) world collection in London and the British fauna to test this method. There has been some discussion as to whether global species estimates are converging (12) or not (13), and here we test this further. M...
This article explores the relative roles of social ties and collective efficacy in explaining community variations in violent victimization in Australia. Using data from a survey of 2,859 residents across 82 communities in the city of Brisbane, coupled with official reported crime data provided by the Queensland Police Service and Australian Bureau of Statistics census data for 2001, the authors employ multilevel statistical models to depict the relative importance of social ties and collective efficacy in predicting between-neighborhood violent victimization in an Australian context. The models include measures of social relationships and communitybased crime prevention programs, and the authors compare and contrast their findings with studies of collective efficacy in Chicago and Stockholm, finding similar results. These findings suggest that despite structural and cultural differences between the United States and Australia in particular, collective efficacy is a significant mechanism in explaining the spatial distribution of self-reported violent victimization in the Australian context. This research underscores the importance of cross-cultural theory testing and the need to further develop the measurement of ecological constructs such as social ties and organizational behavior.
BackgroundIt is generally recognised that continuous quality improvement (CQI) programs support development of high quality primary health care systems. However, there is limited evidence demonstrating their system-wide effectiveness. We examined variation in quality of Type 2 diabetes service delivery in over 100 Aboriginal and Torres Strait Islander primary health care centres participating in a wide-scale CQI project over the past decade, and determined the influence of health centre and patient level factors on quality of care, with specific attention to health centre duration of participation in a CQI program.MethodsWe analysed over 10,000 clinical audit records to assess quality of Type 2 diabetes care of patients in 132 Aboriginal and Torres Strait Islander community health centres in five states/territories participating in the ABCD project for varying periods between 2005 and 2012. Process indicators of quality of care for each patient were calculated by determining the proportion of recommended guideline scheduled services that were documented as delivered. Multilevel regression models were used to quantify the amount of variation in Type 2 diabetes service delivery attributable to health centre or patient level factors and to identify those factors associated with greater adherence to best practice guidelines.ResultsHealth centre factors that were independently associated with adherence to best practice guidelines included longer participation in the CQI program, remoteness of health centres, and regularity of client attendance. Significantly associated patient level variables included greater age, and number of co-morbidities and disease complications. Health centre factors explained 37% of the differences in level of service delivery between jurisdictions with patient factors explaining only a further 1%.ConclusionsAt the health centre level, Type 2 diabetes service delivery could be improved through long term commitment to CQI, encouraging regular attendance (for example, through patient reminder systems) and improved recording and coordination of patient care in the complex service provider environments that are characteristic of non-remote areas.
Aim There is little consensus as to whether stratification of arthropods between canopy and understorey in tropical and subtropical forests is commonplace and if the magnitude of stratification changes across different elevations and latitudes. We investigated broad-scale patterns of vertical stratification of moths collected from extensive cross-continental fieldwork in a variety of forest types, climates, elevations, latitudes and areas with differing biogeographical history.Location Tropical and subtropical rain forest in eastern Australia; tropical, subtropical and subalpine forest in Yunnan Province, China; and tropical rain forest in Panama, Vietnam, Brunei and Papua New Guinea.Methods Night-flying moths were trapped from the upper canopy and understorey. We generated a total of 64 data sets to quantify vertical stratification of moths in terms of their species richness, using coverage-based rarefaction, and assemblage composition, using standardized hierarchical beta diversity. Based on the average temperature lapse rate, we incorporated latitudinal differences into elevation and generated 'corrected' elevation for each location, and analysed its relationships with the magnitude of stratification. ResultsWe found consistent differences between canopy and understorey assemblages at almost all rain forest locations across corrected elevational gradients. The magnitude of vertical stratification in species richness did not change with increasing corrected elevation. In contrast, the difference in assemblage composition increased with increasing corrected elevation in the Northern Hemisphere, while the opposite, albeit weak, trend was found in the Southern Hemisphere.Main conclusions Clear vertical stratification was evident in moth assemblages regardless of elevation and latitude. However, the degree to which assemblages are stratified between canopy and understorey is not uniformly related to elevation and latitude. Inconsistencies in the magnitude of vertical stratification between the Northern and Southern Hemisphere, may reflect, on one hand, deep-time biogeographical differences between the land masses studied and, on the other, place-to-place differences in resource availability underpinning the observed moth assemblages.
A number of marine microalgae are known to produce toxins that can accumulate in shellfish and when eaten, lead to toxic and potentially fatal reactions in humans. This paper reports on the occurrence and seasonal variations of algal toxins in the waters, phytoplankton and shellfish of Southeast Queensland, Australia. These algal toxins include okadaic acid (OA), domoic acid (DA), gymnodimine (GD), pectenotoxin-2 (PTX-2) and pectenotoxin-2-seco acid (PTX-2-SA), which were detected in the sampled shellfish and phytoplankton, via HPLC-MS/MS. Dissolved OA, PTX-2 and GD were also detected in the samples collected from the water column. This was the first occasion that DA and GD have been reported in shellfish, phytoplankton and the water column in Queensland waters. Phytoplankton tows contained both the toxic Dinophysis and Pseudo-nitzschia algae species, and are suspected of being the most likely producers of the OA, PTX-2s and DA found in shellfish of this area. The number of cells, however, did not correlate with the amount of toxins present in either shellfish or phytoplankton. This indicates that toxin production by algae varies with time and the species present and that number of cells alone cannot be used as an indicator for the presence of toxins. The presence of OA and PTX-2s were more frequently seen in the summer, while DA and GD were detected throughout the year and without any obvious seasonal patterns.
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