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Gateway science courses are an ongoing obstacle to recruitment into STEM (Science, Technology, Engineering, and Mathematics) fields, in part due to the large gains in vocabulary that are fundamenta...

Target two of the 2002 Global Strategy for Plant Conservation (GSPC), “A preliminary assessment of the conservation status of all known plant species, at national, regional, and international levels” was not accomplished by its original 2010 target date and has therefore been included as a revised 2020 target, “An assessment of the conservation status of all known plant species, as far as possible, to guide conservation action.” The most widely used system to estimate risk of extinction, the International Union for the Conservation of Nature Red List, provides conservation assessments for fewer than 15,000 plant species. Progress achieving Target two has been hampered by the large number of plant species and the difficulty assembling the data needed for Red List assessments. Two streamlined methods for identifying those plant species considered At Risk under the GSPC Target two are compared and contrasted. Both methods use readily available locality data from herbarium specimens to efficiently identify At Risk species and approximate the list of species that would be identified as threatened by Red List analyses. A comprehensive analysis of the native plant species of Puerto Rico using both streamlined methods identifies 570 of the 2,025 species at some risk of extinction. More efficient systems for assessing threat allow a more timely response to Target two, allow conservation efforts to be directed to the species that need attention, and the list of threatened plants can be used to identify priority areas for plant conservation.

Threat analyses of the Boraginales were conducted and used to assess the effectiveness of Madagascar’s current and proposed protected area systems in conserving the threatened species of a group of plants widespread in Madagascar. Specimen locality data for 52 species of four families of Boraginales were analysed to provisionally assign species to IUCN Red List categories. Six species were excluded from these global analyses as they are non-native and introduced. IUCN’s criterion B, analysis of geographical range, was found to be the most reliable means of estimating threat, and predicted future decline was found to overestimate threat. Twenty-six of the 46 native species of Boraginales were found to be threatened. Sixty-five percent of these have portions of their ranges in the 2002 protected areas system. When the protected areas system was expanded in 2006 the percentage of species with some protected populations increased to 78%. More than 93% would be protected if a series of proposed priority areas for plant conservation were protected. The implications of these analyses for the conservation of plant species in Madagascar are discussed.

Determining an accurate depiction of population distribution for urban areas in order to develop an improved "denominator" is important for the calculation of higher-precision rates in GIS analyses, particularly when exploring the spatial dynamics of disease. Rather than using data aggregated by arbitrary administrative boundaries such as census tracts, we developed the Cadastral-Based Expert Dasymetric System (CEDS), an interpolation method using ancillary information to delineate areas of homogeneous values. This method uses cadastral data, land-use filters, modeling by expert system routines, and validation against various census enumeration units and other data. The CEDS method is presented through a case study of asthma hospitalizations in the borough of the Bronx in New York City, in relation to proximity buffers constructed around major sources of air pollution. The analysis using CEDS shows that asthma hospitalization risk due to proximity to pollution sources is greater than previously calculated...

Of the twelve species ofChamaedorea palm recorded for Belize, three are of international economic value because their cut leaves (xate) are traded in the floricultural industry. Traditionally, Belize has not harvested xate, the industry being based in Mexico and Guatemala. However, a decline in wild xate stocks in these countries means Guatemalan leaf harvesters now illegally harvest xate in Belize. To assess the local abundance of the BelizeanChamaedorea resource, its economic value, and the extent to which it has been illegally harvested, 209 plots measuring 20 meters (m) by 20 m were established in the Greater Maya Mountains (GMM) in western Belize, which includes the Chiquibul Forest Reserve (CFR). We estimate that 37.8 million leaves with a value of U.S. $0.3 million to xateros have been extracted from the CFR. The standing export value is calculated as U.S. $1.8 million for the CFR and U.S. $5 million for the GMM.

Background The tropical rain forests (TRF) of Africa are the second largest block of this biome after the Amazon and exhibit high levels of plant endemism and diversity. Two main hypotheses have been advanced to explain speciation processes that have led to this high level of biodiversity: allopatric speciation linked to geographic isolation and ecological speciation linked to ecological gradients. Both these hypotheses rely on ecology: in the former conservation of ecological niches through time is implied, while in the latter adaptation via selection to alternative ecological niches would be a prerequisite. Here, we investigate the role of ecology in explaining present day species diversity in African TRF using a species level phylogeny and ecological niche modeling of two predominantly restricted TRF tree genera, Isolona and Monodora (Annonaceae). Both these genera, with 20 and 14 species, respectively, are widely distributed in African TRFs, with a few species occurring in slightly less humid regions such as in East Africa. Results A total of 11 sister species pairs were identified most of them occurring in allopatry or with little geographical overlap. Our results provide a mixed answer on the role of ecology in speciation. Although no sister species have identical niches, just under half of the tests suggest that sister species do have more similar niches than expected by chance. PCA analyses also support little ecological differences between sister species. Most speciation events within both genera predate the Pleistocene, occurring during the Late Miocene and Pliocene periods. Conclusions Ecology is almost always involved in speciation, however, it would seem to have had a little role in species generation within Isolona and Monodora at the scale analyzed here. This is consistent with the geographical speciation model for TRF diversification. These results contrast to other studies for non-TRF plant species where ecological speciation was found to be an important factor of diversification. The Pliocene period appears to be a vital time in the generation of African TRF diversity, whereas Pleistocene climatic fluctuations have had a smaller role on speciation than previously thought. Ecological niche modeling, species level phylogeny, ecological speciation, African tropics, Isolona, Monodora, Annonaceae