We present the most extensive examination to date of proposed correlates of species richness. We use rigorous phylogenetic comparative techniques, data for 1,692 mammal species in four clades, and multivariate statistics to test four hypotheses about species richness and compare the evidence for each. Overall, we find strong support for the life-history model of diversification. Species richnes...

A general model linking environmental fluctuations and species richness is proposed. This model includes two important biological mechanisms. A first term describes the global negative effect of fluctuations on richness via stress and density-independent mortality; a second term represents the positive effect of perturbations on richness by competitive relaxation. Both effects are modeled as ex...

The consistent decrease in species richness with latitude shows several exceptions among marine organisms. We hypothesize that contrasting latitudinal diversity gradients can be explained by differences in critical life-history attributes, such as mode of larval development (MLD). We deconstructed latitudinal species richness patterns of marine benthic invertebrates according to MLD to elucidat...

Spatial patterns of species richness follow climatic and environmental variation, but could reflect random dynamics of species ranges (the mid-domain effect, MDE). Using data on the global distribution of birds, we compared predictions based on energy availability (actual evapotranspiration, AET, the best single correlate of avian richness) with those of range dynamics models. MDE operating wit...

Much recent research explaining plant community diversity has focused on comparing the relative impacts of regional and local processes. We employed a novel analysis to quantify the effects of multiple regional and local processes on species richness, and to make quantitative comparisons of those effects across two sites that differ in plot-level species richness, productivity and environmental...

Minimizing the scatter between cluster mass and accessible observables is an important goal for cluster cosmology. In this work, we introduce a new matched filter richness estimator, and test its performance using the maxBCG cluster catalog. Our new estimator significantly reduces the variance in the LX −richness relation, from σ2 ln LX = (0.86± 0.02)2 to σ2 ln LX = (0.69± 0.02)2. Relative to t...

vegetation studies measuring the accuracy of the results is important. the purpose of this study is to compare shape and distribution plots on different levels for species richness measurements.thiscomparison was in three design whittaker, stohlgern and a new design (ariz) in ariz, sanandaj.designed proposition (ariz) obtainedon base changes in the size and distribution plotin design stohlgern ...

A study in Nature by Fischer et al. shows that environmental enrichment or increasing histone acetylation rescue the ability to form new memories and re-establish access to remote memories even in the presence of brain degeneration. Chromatin remodeling may be the final gate environmental enrichment opens to enhance plasticity and represents a promising target for therapeutical intervention in ...

Microorganisms are spectacularly diverse phylogenetically, but available estimates of their species richness are vague and problematic. For example, for comparable environments, the estimated numbers of species range from a few dozen or hundreds to tens of thousands and even half a million. Such estimates provide no baseline information on either local or global microbial species richness. We a...

can be found at: Progress in Physical Geography Additional services and information for http://ppg.sagepub.com/cgi/alerts Email Alerts: http://ppg.sagepub.com/subscriptions Subscriptions: http://www.sagepub.com/journalsReprints.nav Reprints: http://www.sagepub.com/journalsPermissions.nav Permissions: http://ppg.sagepub.com/cgi/content/refs/24/1/117 SAGE Journals Online and HighWire Press plat...