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181.
182.
New baseline environmental assessment of mosquito ecology in northern Haiti during increased urbanization
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Dayana M. Samson Reginald S. Archer Temitope O. Alimi Kristopher L. Arheart Daniel E. Impoinvil Roland Oscar Douglas O. Fuller Whitney A. Qualls 《Journal of vector ecology》2015,40(1):46-58
The catastrophic 2010 earthquake in Port‐au‐Prince, Haiti, led to the large‐scale displacement of over 2.3 million people, resulting in rapid and unplanned urbanization in northern Haiti. This study evaluated the impact of this unplanned urbanization on mosquito ecology and vector‐borne diseases by assessing land use and change patterns. Land‐use classification and change detection were carried out on remotely sensed images of the area for 2010 and 2013. Change detection identified areas that went from agricultural, forest, or bare‐land pre‐earthquake to newly developed and urbanized areas post‐earthquake. Areas to be sampled for mosquito larvae were subsequently identified. Mosquito collections comprised five genera and ten species, with the most abundant species being Culex quinquefasciatus 35% (304/876), Aedes albopictus 27% (238/876), and Aedes aegypti 20% (174/876). All three species were more prevalent in urbanized and newly urbanized areas. Anopheles albimanus, the predominate malaria vector, accounted for less than 1% (8/876) of the collection. A set of spectral indices derived from the recently launched Landsat 8 satellite was used as covariates in a species distribution model. The indices were used to produce probability surfaces maps depicting the likelihood of presence of the three most abundant species within 30 m pixels. Our findings suggest that the rapid urbanization following the 2010 earthquake has increased the amount of area with suitable habitats for urban mosquitoes, likely influencing mosquito ecology and posing a major risk of introducing and establishing emerging vector‐borne diseases. 相似文献
183.
Zachary L. Fuller Elina L. Ni?o Harland M. Patch Oscar C. Bedoya-Reina Tracey Baumgarten Elliud Muli Fiona Mumoki Aakrosh Ratan John McGraw Maryann Frazier Daniel Masiga Stephen Schuster Christina M. Grozinger Webb Miller 《BMC genomics》2015,16(1)
Background
With the development of inexpensive, high-throughput sequencing technologies, it has become feasible to examine questions related to population genetics and molecular evolution of non-model species in their ecological contexts on a genome-wide scale. Here, we employed a newly developed suite of integrated, web-based programs to examine population dynamics and signatures of selection across the genome using several well-established tests, including FST, pN/pS, and McDonald-Kreitman. We applied these techniques to study populations of honey bees (Apis mellifera) in East Africa. In Kenya, there are several described A. mellifera subspecies, which are thought to be localized to distinct ecological regions.Results
We performed whole genome sequencing of 11 worker honey bees from apiaries distributed throughout Kenya and identified 3.6 million putative single-nucleotide polymorphisms. The dense coverage allowed us to apply several computational procedures to study population structure and the evolutionary relationships among the populations, and to detect signs of adaptive evolution across the genome. While there is considerable gene flow among the sampled populations, there are clear distinctions between populations from the northern desert region and those from the temperate, savannah region. We identified several genes showing population genetic patterns consistent with positive selection within African bee populations, and between these populations and European A. mellifera or Asian Apis florea.Conclusions
These results lay the groundwork for future studies of adaptive ecological evolution in honey bees, and demonstrate the use of new, freely available web-based tools and workflows (http://usegalaxy.org/r/kenyanbee) that can be applied to any model system with genomic information.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1712-0) contains supplementary material, which is available to authorized users. 相似文献184.
Martin F. J. Taylor Paul S. Sattler Megan Evans Richard A. Fuller James E. M. Watson Hugh P. Possingham 《Biodiversity and Conservation》2011,20(4):767-777
Despite the growing numbers of threatened species and high levels of spending on their recovery worldwide, there is surprisingly
little evidence about which conservation approaches are effective in arresting or reversing threatened species declines. Using
two government data sets, we examined associations between population trends for 841 nationally-threatened terrestrial species
in Australia, and four measures of conservation effort: (a) how much their distribution overlaps with strictly protected areas
(IUCN I–IV), (b) and other protected areas (IUCN V–VI), (c) the number of recovery activities directed at the species, and
(d) numbers of natural resource conservation activities applied in areas where populations of the threatened species occur.
We found that all populations of 606 (72%) species were in decline. Species with greater distributional overlap with strictly
protected areas had proportionately more populations that were increasing or stable. This effect was robust to geographic
range size, data quality differences and extent of protection. Measures other than strictly protected areas showed no positive
associations with stable or increasing trends. Indeed, species from regions with more natural resource conservation activities
were found to be more likely to be declining, consistent with differential targeting of such generalised conservation activities
to highly disturbed landscapes. Major differences in trends were also found among the different jurisdictions in which species
predominantly occurred, which may be related to different legislative protections against habitat destruction. Although we
were not able to test causation, this research corroborates other evidence that protected areas contribute to the stabilization
or recovery of threatened species, and provides little empirical support for other conservation approaches. 相似文献
185.
186.
Rodney J. Fuller Vincent M. Liddiard J. Richard Hess John G. Carman 《In vitro cellular & developmental biology. Plant》2011,47(3):410-419
Plant ovules provide zygotes with a physicochemical environment that supports embryo differentiation, growth, and maturation.
The exact nature of this embryogenesis-enabling environment is not well characterized, as evidenced by failed attempts to
induce normal embryony from zygotes or proembryos (precotyledonary) on defined media. To identify factors required for cotton
(Gossypium hirsutum L.) zygotic embryony in vitro, we previously performed chemical and dissolved oxygen tension analyses of cotton ovule fluids and tissues at multiple stages
of embryony in situ. Based on these analyses, we report herein the development of procedures that normalize embryo differentiation, growth, maturation,
and germination in vitro, starting with proembryos. Our medium differed from Murashige and Skoog (MS) medium as follows (percentage of MS): N (30%,
mostly from ten amino acids), P (815%), K (237%), Mg (85%), Ca (267%), S (506%), Fe (88%), and myoinositol (883%). Levels
of other MS nutrients and vitamins, except sucrose, were kept at MS levels. Additionally, we included 100 mg L−1 casein hydrolysate plus the following (mmol L−1): d-glucose (1.8), fructose (4.7), sucrose (62.0), arabinose (7.1), melibiose (3.5), malic acid (11.6), and citric acid (3.8).
Mannitol was added to achieve a medium osmotic potential of −1.10 MPa, and an atmospheric O2 tension of 3.3 mol m−3 at the surface of embryos was maintained during culture. When cultured on medium containing 8.0 μmol L−1 indole-3-acetic acid, 80–90% of proembryos (as small as 100 cells) of cultivars HS-26 and B-27 increased four- to eightfold
in surface area during the first 18 d in culture and germinated thereafter to produce viable plants. Increases in surface
area of proembryos cultured on a modified MS medium previously used for somatic embryogenesis were from 0.2- to 0.6-fold.
The described embryo culture medium should be useful for studying nutritional and molecular aspects of early embryony and
possibly for plant zygote transformation protocols. 相似文献
187.
The chromosomal passenger complex (CPC), containing Aurora B kinase, Inner Centromere Protein, Survivin, and Borealin, regulates chromosome condensation and interaction between kinetochores and microtubules at metaphase, then relocalizes to midzone microtubules at anaphase and regulates central spindle organization and cytokinesis. However, the precise role(s) played by the CPC in anaphase have been obscured by its prior functions in metaphase. Here we identify a missense allele of Drosophila Survivin that allows CPC localization and function during metaphase but not cytokinesis. Analysis of mutant cells showed that Survivin is essential to target the CPC and the mitotic kinesin-like protein 1 orthologue Pavarotti (Pav) to the central spindle and equatorial cell cortex during anaphase in both larval neuroblasts and spermatocytes. Survivin also enabled localization of Polo kinase and Rho at the equatorial cortex in spermatocytes, critical for contractile ring assembly. In neuroblasts, in contrast, Survivin function was not required for localization of Rho, Polo, or Myosin II to a broad equatorial cortical band but was required for Myosin II to transition to a compact, fully constricted ring. Analysis of this "separation-of-function" allele demonstrates the direct role of Survivin and the CPC in cytokinesis and highlights striking differences in regulation of cytokinesis in different cell systems. 相似文献
188.
Marco Pautasso Katrin Böhning‐Gaese Philippe Clergeau Victor R. Cueto Marco Dinetti Esteban Fernández‐Juricic Marja‐Liisa Kaisanlahti‐Jokimäki Jukka Jokimäki Michael L. McKinney Navjot S. Sodhi David Storch Ludwik Tomialojc Peter J. Weisberg John Woinarski Richard A. Fuller Elena Cantarello 《Global Ecology and Biogeography》2011,20(3):426-436
Aim Despite the increasing pace of urbanization, little is known about how this process affects biodiversity globally. We investigate macroecological patterns of bird assemblages in urbanized areas relative to semi‐natural ecosystems. Location World‐wide. Methods We use a database of quantitative bird surveys to compare key assemblage structure parameters for plots in urbanized and semi‐natural ecosystems controlling for spatial autocorrelation and survey methodology. We use the term ‘urbanized’ instead of ‘urban’ ecosystems as many of the plots were not located in the centre of towns but in remnant habitat patches within conurbations. Results Some macroecological relationships were conserved in urbanized landscapes. Species–area, species–abundance and species–biomass relationships did not differ significantly between urbanized and non‐urbanized environments. However, there were differences in the relationships between productivity and assemblage structure. In forests, species richness increased with productivity; in both forests and open habitats, the evenness of species abundances declined as productivity increased. Among urbanized plots, instead, both species richness and the evenness of species abundances were independent of variation in productivity. Main conclusions Remnant habitats within urbanized areas are subject to many ecological alterations, yet key macroecological patterns differ remarkably little in urbanized versus non‐urbanized plots. Our results support the need for increased conservation activities in urbanized landscapes, particularly given the additional benefits of local experiences of biodiversity for the human population. With increasing urbanization world‐wide, broad‐scale efforts are needed to understand and manage the effects of this driver of change on biodiversity. 相似文献
189.
190.
Aim A previous study of the allodapine bee genus Braunsapis suggested an African origin, with dispersal events into Madagascar and Asia, and from Asia into Australia. We re‐examine the phylogeny of this genus, using an expanded set of taxa from Madagascar and Malawi and additional sequence data, in order to determine the number of dispersals and the timeframe over which they occurred. Location Africa, Madagascar, Malawi, Asia and Australia. Methods One nuclear (EF‐1α F2) and two mitochondrial (CO1 and Cyt b) gene regions were sequenced for 36 allodapine bee species (including members of the genera Braunsapis, Nasutapis, Allodape, Allodapula, and Macrogalea) and one ceratinine species (Ceratina japonica). We used Bayesian analyses to examine phylogenetic structure and a penalized likelihood approach to estimate approximate ages for key divergences in our phylogeny. Results Our analyses indicate a tropical African origin for Braunsapis in the early Miocene followed by very early dispersal into Asia and then a subsequent dispersal, following Asian diversification, into Australia during the late Miocene. There have also been two dispersals of Braunsapis from Africa to Madagascar and this result, when combined with phylogenetic and biogeographical data for other allodapines, suggests that these bees have the ability to cross moderately large ocean expanses. These dispersals may have been aided by the West Wind Drift, but rafting across the Mozambique Channel is also possible, and could be aided by the existence of developmental stages that require minimal or no feeding and by tolerance to sea water and spume. Accumulating evidence suggests that many biogeographical patterns in the southern hemisphere may be better explained by dispersal than by Gondwanan vicariance hypotheses. Our results add to this growing body of data and raise the possibility that some puzzling trans‐Indian Ocean distributions may also be explained by historical dispersal events across oceanic barriers that now seem insuperable. 相似文献