34 research outputs found

    Community ecology of the Middle Miocene primates of La Venta, Colombia: the relationship between ecological diversity, divergence time, and phylogenetic richness

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    It has been suggested that the degree of ecological diversity that characterizes a primate community correlates positively with both its phylogenetic richness and the time since the members of that community diverged (Fleagle and Reed in Primate communities. Cambridge University Press, New York, pp 92–115, 1999). It is therefore questionable whether or not a community with a relatively recent divergence time but high phylogenetic richness would be as ecologically variable as a community with similar phylogenetic richness but a more distant divergence time. To address this question, the ecological diversity of a fossil primate community from La Venta, Colombia, a Middle Miocene platyrrhine community with phylogenetic diversity comparable with extant platyrrhine communities but a relatively short time since divergence, was compared with that of modern Neotropical primate communities. Shearing quotients and molar lengths, which together are reliable indicators of diet, for both fossil and extant species were plotted against each other to describe the dietary “ecospace” occupied by each community. Community diversity was calculated as the area of the minimum convex polygon encompassing all community members. The diversity of the fossil community was then compared with that of extant communities to test whether the fossil community was less diverse than extant communities while taking phylogenetic richness into account. Results indicate that the La Ventan community was not significantly less ecologically diverse than modern communities, supporting the idea that ecological diversification occurred along with phylogenetic diversification early in platyrrhine evolution

    Stores healthy options project in remote indigenous communities (SHOP@RIC): a protocol of a randomised trial promoting healthy food and beverage purchases through price discounts and in-store nutrition education

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    BackgroundIndigenous Australians suffer a disproportionate burden of preventable chronic disease compared to their non-Indigenous counterparts – much of it diet-related. Increasing fruit and vegetable intakes and reducing sugar-sweetened soft-drink consumption can reduce the risk of preventable chronic disease. There is evidence from some general population studies that subsidising healthier foods can modify dietary behaviour. There is little such evidence relating specifically to socio-economically disadvantaged populations, even though dietary behaviour in such populations is arguably more likely to be susceptible to such interventions.This study aims to assess the impact and cost-effectiveness of a price discount intervention with or without an in-store nutrition education intervention on purchases of fruit, vegetables, water and diet soft-drinks among remote Indigenous communities.Methods/DesignWe will utilise a randomised multiple baseline (stepped wedge) design involving 20 communities in remote Indigenous Australia. The study will be conducted in partnership with two store associations and twenty Indigenous store boards. Communities will be randomised to either i) a 20% price discount on fruit, vegetables, water and diet soft-drinks; or ii) a combined price discount and in-store nutrition education strategy. These interventions will be initiated, at one of five possible time-points, spaced two-months apart. Weekly point-of-sale data will be collected from each community store before, during, and for six months after the six-month intervention period to measure impact on purchasing of discounted food and drinks. Data on physical, social and economic factors influencing weekly store sales will be collected in order to identify important covariates. Intervention fidelity and mediators of behaviour change will also be assessed.DiscussionThis study will provide original evidence on the effectiveness and cost-effectiveness of price discounts with or without an in-store nutrition education intervention on food and drink purchasing among a socio-economically disadvantaged population in a real-life setting

    Correlates of sunscreen use among high school students: a cross-sectional survey

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    Abstract Background Adolescents put themselves at risk of later skin cancer development and accelerated photo-aging due to their high rates of ultraviolet radiation exposure and low rates of skin protection. The purpose of the current study was to determine which of the Integrative Model constructs are most closely associated with sunscreen use among high school students. Methods The current study of 242 high school students involved a survey based on the Integrative Model including demographic and individual difference factors, skin protection-related beliefs and outcome evaluations, normative beliefs, self-efficacy, sunscreen cues and availability, intentions, and sunscreen use. Our analyses included multiple linear regressions and bootstrapping to test for mediation effects. Results Sunscreen use was significantly associated with female gender, greater skin sensitivity, higher perceived sunscreen benefits, higher skin protection importance, more favorable sunscreen user prototype, stronger skin protection norms, greater perceived skin protection behavioral control, and higher sunscreen self-efficacy. Intentions to use sunscreen mediated the relationships between most skin protection-related beliefs and sunscreen use. Conclusions The current study identified specific variables that can be targeted in interventions designed to increase sunscreen use among adolescents.</p

    Small mammal responses to Amazonian forest islands are modulated by their forest dependence

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    Hydroelectric dams have induced widespread loss, fragmentation and degradation of terrestrial habitats in lowland tropical forests. Yet their ecological impacts have been widely neglected, particularly in developing countries, which are currently earmarked for exponential hydropower development. Here we assess small mammal assemblage responses to Amazonian forest habitat insularization induced by the 28-year-old Balbina Hydroelectric Dam. We sampled small mammals on 25 forest islands (0.83–1466 ha) and four continuous forest sites in the mainland to assess the overall community structure and species-specific responses to forest insularization. We classified all species according to their degree of forest-dependency using a multi-scale approach, considering landscape, patch and local habitat characteristics. Based on 65,520 trap-nights, we recorded 884 individuals of at least 22 small mammal species. Species richness was best predicted by island area and isolation, with small islands ( 200 ha; 10.8 ± 1.3 species) and continuous forest sites (∞ ha; 12.5 ± 2.5 species) exhibited similarly high species richness. Forest-dependent species showed higher local extinction rates and were often either absent or persisted at low abundances on small islands, where non-forest-dependent species became hyper-abundant. Species capacity to use non-forest habitat matrices appears to dictate small mammal success in small isolated islands. We suggest that ecosystem functioning may be highly disrupted on small islands, which account for 62.7% of all 3546 islands in the Balbina Reservoir
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