We treat analytically the model of Tilman et al. and investigate

We treat analytically the model of Tilman et al. and investigate three different scenarios. We consider that before destruction: (i) best competitors are most abundant; (ii) all species are equally abundant; (iii) poor competitors are most abundant. In each case, we have derived explicit expressions for equilibrium species abundances depending on proportion of destroyed sites. Then we follow analytically alteration in the initial abundance ranking, show complex patterns Of Succession of species abundances and consider transformations in the rank-abundance curve. We demonstrate

patterns of self-organization in abundance distributions emerging as a response Selleck AZD1480 to habitat destruction. We show non-monotonic dependence of community diversity and community evenness on proportion of destroyed sites. (c) 2008 Elsevier Ltd. All rights check details reserved.”
“Early-onset, severe retinal

dystrophy caused by mutations in the gene encoding retinal pigment epithelium-specific 65-kD protein (RPE65) is associated with poor vision at birth and complete loss of vision in early adulthood. We administered to three young adult patients subretinal injections of recombinant adeno-associated virus vector 2/2 expressing RPE65 complementary DNA (cDNA) under the control of a human RPE65 promoter. There were no serious adverse events. There was no clinically significant change in visual acuity or in peripheral visual fields on Goldmann perimetry in any of the three patients. We detected no change in retinal responses on electroretinography. One patient had significant improvement in visual function on microperimetry and on dark-adapted perimetry. This patient also showed improvement in a subjective Idasanutlin datasheet test of visual mobility. These findings provide support for further clinical studies of this experimental approach in other patients with mutant RPE65.”
“Evolutionary distinctiveness measures of how evolutionarily isolated a species is relative to other members of its clade. Recently, distinctiveness metrics that explicitly incorporate time have been proposed for conservation prioritization. However,

we found that such measures differ qualitatively in how well they capture the total amount of evolution (termed phylogenetic diversity, or PD) represented by a set of species. We used simulation and simple graph theory to explore this relationship with reference to phylogenetic tree shape. Overall, the distinctiveness measures capture more PD on more unbalanced trees and on trees with many splits near the present. The rank order of performance was robust across tree shapes, with apportioning measures performing best and node-based measures performing worst. A sample of 50 ultrametric trees from the literature showed the same patterns. Taken together, this suggests that distinctiveness metrics may be a useful addition to other measures of value for conservation prioritization of species.

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