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Increasing rates of habitat loss and human occupation are creating demands for optimum strategies that maximize conservation efforts, despite the lack of detailed data required for implementation. Broad scale biogeographical data may furnish initial guidelines for conservation planning in a hierarchical framework for establishing conservation priorities and helping guide future research programmes. This approach may be critical in regions for which few detailed data on diversity, abundance and distribution are available, such as in the Cerrado biome of central Brazil. We used a macroecological approach, based on the extent of occurrence of 127 species of terrestrial vertebrates endemic to the Cerrado, to design a regional network of potential areas that represent all species at least once. The final network has a total of 24 regions widely distributed throughout the biome. We also evaluated these regions in terms of their human occupation by adding a cost for each cell based on 23 variables expressing variation in agricultural, demographic and cattle-ranching patterns on the Cerrado. Our analyses showed that conservation efforts should be concentrated in the south and south-east of the biome. This macro- ecological approach can provide broad guidelines for conservation and define the focus for more local and realistic conservation efforts. [ABSTRACT FROM AUTHOR]

To quantify the relationship between the description dates of anuran species in the Brazilian Cerrado and some macroecological traits, and to verify the spatial patterns of average description dates and their correlation with human occupation and biodiversity knowledge. Brazilian Cerrado (South America). The average date of description of 131 species of anurans found in 181 cells overlaying the Brazilian Cerrado was recorded. Description date was regressed across species on body size and geographical range size. Phylogenetic effects that could bias the significance tests of the multiple regression model of description dates on macroecological traits were taken into account using a phylogenetic subtraction method in which families and genera were classificatory factors in a nested two-way analysis of variance ( anova) model. We also conducted a spatial analysis of the average description date that was estimated for each cell. This cell-based metric was regressed on human population size, the year of foundation of the municipalities and the number of inventories undertaken in each cell. The influence of spatial autocorrelation patterns was taken into account by using the geographically effective number of degrees of freedom. The number of new species being discovered in the Brazilian Cerrado has been increasing, especially over the last 50 years. Cross-species analyses indicated that description dates were negatively correlated with body size and geographical range size, taking phylogenetic effects into account. Even after controlling for the spatial structures in all variables, average description date was positively correlated with human population in geographical space, but because of multicolinearity structure in the data, it was not possible to quantify the independent influence of human population and number of inventories on description date. As found in previous papers, large-bodied and widely distributed species are likely to be described first. Species yet to be discovered are probably small-bodied and with narrow distributions, more restricted to the Cerrado biome. Also, the explicit spatial approach showed that the average description date is spatially correlated with total human population and biodiversity knowledge in the Cerrado region. Our findings suggest that incorporating human population density into the reserve design algorithms, which has usually been done to avoid or minimize conservation conflicts, may also produce good results because this will preserve many places where most of the non-described species will probably be found in the future. [ABSTRACT FROM AUTHOR]

Abstract: Macroecology deals with variation and covariation of complex variables, such as body size, population density and geographic range size (GRS), measured across species at broad spatial scales. Despite the increasing number of papers in this field, little attention has been given to the links between patterns at different scales. In this paper, we analysed the constraint envelope formed by the macroecological relationship between GRS and body size for 70 species of New World terrestrial Carnivora. The lower-right constraint line of this envelope is usually interpreted as the minimum viable GRS that keeps extinction risks relatively low across evolutionary time, and in this paper we fitted this line by multiplying average home range size (established by allometric equations) by different minimum viable population sizes, establishing a minimum viable GRS. Then we estimated the difference between actual geographical range size and minimum viable geographical range size, in log scale (ΔA), which indicates how large is the geographic range of a species in relation to the minimum necessary to its long-term persistence. These ΔA values are significantly correlated with extinction risk defined by IUCN threat categories, even after keeping geographical range size constant and after taking into account phylogenetic structure in data. This gives support to the minimum viable population model explaining the relationship between GRS and body size and highlights a way to use constraint envelopes to evaluate the influence of complex variables to predict extinction risks. [Copyright &y& Elsevier]