A5022139986- Ecology and Vegetation Dynamics Studies
- Plant and animal studies
- Statistics Education and Methodologies
- Botany and Plant Ecology Studies
- Advanced Statistical Methods and Models
- Evolution and Paleontology Studies
- Statistical Methods and Bayesian Inference
- Rangeland and Wildlife Management
- Forecasting Techniques and Applications
- Pasture and Agricultural Systems
- Bayesian Modeling and Causal Inference
- Employment and Welfare Studies
- Data Mining Algorithms and Applications
- Bayesian Methods and Mixture Models
- Algorithms and Data Compression
- Species Distribution and Climate Change
- Global Public Health Policies and Epidemiology
- Spectroscopy and Chemometric Analyses
- Opinion Dynamics and Social Influence
- Genetic diversity and population structure
- Innovations in Educational Methods
- Plant Diversity and Evolution
- Viral gastroenteritis research and epidemiology
- Animal Virus Infections Studies
- Botany, Ecology, and Taxonomy Studies
The Open University
2011-2023
Royal Statistical Society
2021
Universidade Aberta
2010
Hong Kong Metropolitan University
2003
Queen Mary University of London
1982
University of London
1982
R. H. Whittaker's idea that plant diversity can be divided into a hierarchy of spatial components from α at the within-habitat scale through β for turnover species between habitats to γ along regional gradients implies underlying existence α, β, and niches. We explore hypothesis evolution niches is also hierarchical, with traits define niche being labile, while those defining are conservative. At level we find support in lack close significant phylogenetic relationship meadow have similar In...
See also the Commentary by Peuelas et al .
Abstract Suppose a decision maker has asked group of experts to assess subjective probability distributions over some space, and he wishes find consensus distribution as function these. The assumption that finding the commutes with marginalization implies must be found using linear opinion pool (weighted average), provided space being considered contains three or more points. Some consequences this result are discussed.
We used data on grassland plant community composition over a 90—yr period in the history of Park Grass Experiment, England to look for relationship between variation and annual rainfall biomass. This was investigated by regressions biomass each other, these variables separately three different measures composition. Two measures, principal components analysis scores based species abundance ratio mass nongrass/grass species, showed significant relationships with many experimental plots,...
A significant proportion of the global diversity flowering plants has evolved in recent geological time, probably through adaptive radiation into new niches. However, rapid evolution is at odds with research which suggested that plant ecological traits, including β- (or habitat) niche, evolve only slowly. We have quantified traits determine within-habitat α (α niches) two communities species segregate on hydrological gradients. Molecular phylogenetic analysis these data shows practically no...
Organisms provide some of the most sensitive indicators climate change and evolutionary responses are becoming apparent in species with short generation times. Large datasets on genetic polymorphism that can an historical benchmark against which to test for recent very rare, but exception is found brown-lipped banded snail (Cepaea nemoralis). This its thermal environment exhibits several polymorphisms shell colour banding pattern affecting albedo majority populations within native range...
Accurate species identification is fundamental to biodiversity science, but the natural history skills required for this are neglected in formal education at all levels. In paper we describe how web application ispotnature.org and its sister site ispot.org.za (collectively, "iSpot") helping solve problem by combining learning technology with crowdsourcing connect beginners experts. Over 94% of observations submitted iSpot receive a determination. External checking sample 3,287 records...
The global extinction of species proceeds through the erosion local populations. Using a 60-year time series annual sighting records plant species, we studied correlates risk associated with in Park Grass Experiment where plants received long-term exposure to nutrient enrichment, soil acidification, and reductions habitat size. We used multivariate linear models assess how extrinsic threats life history traits influence risk. investigated effects four (nitrogen productivity, plot size) as...
Summary 1. Volunteers have helped in scientific surveys of birds and other organisms for decades, but more recently, the use Internet has enormously widened opportunity citizen science greatly increased its practice. There is now a need to share experience which methods work do not. Here, we describe how planned executed Evolution MegaLab, one largest polymorphism wild species so far undertaken. 2. The aim MegaLab was exploit occasion Charles Darwin’s double centenary 2009 mobilize widest...
1.The CSR theory of life-history strategies Grime, and demographically based theories life history represent strongly contrasting approaches that have yet to be reconciled. 2. It is argued there are a priori grounds for analogy between Grime's three primary the established phase in plants demographic processes growth (≈C), survival (≈S), fecundity (≈R). 3. The contribution growth, finite rate population increase λ was calculated populations 18 plant species also been classified according...
1 A 60-year time-series of species recorded in visual surveys the plant communities Park Grass Experiment is analysed to detect changes through time frequency on seven plots with acidified soil and 35 non-acidified plots. 2 Of 14 plots, eight decreased time, one (Agrostis capillaries) increased, four showed no trend (Chamerion angustifolium) an outbreak a peak 1946. 43 nonacidified six five decreased, 10 outbreaks 22 trend. 3 We used discriminant analysis try identify combinations...
The Park Grass Experiment (PGE), begun at Rothamsted Experimental Station in 1856 and still running, affords a unique opportunity to test for the influence of species number soil reaction on biomass variability suite comparable plant communities. Biomass was measured by calculating coefficient variation ( CV ) over time annual hay yield an eleven-year moving window. were both strongly negatively correlated with biomass; relations affected pH. Multiple regression mean nonacidified plots 42...
Abstract A standard approach to the combination of probabilistic opinions involves taking a weighted linear average individuals distributions. This paper reviews some possible interpretations that have been proposed for these weights in literature on expert use. Several paradigms selecting are also considered. Special attention is devoted Bayesian mechanism used updating face new information. An asymptotic result proved which highlights importance choosing initial carefully.
When a panel of experts is asked to provide some advice in the form group probability distribution, question arises as whether they should synthesize their opinions before or after learn outcome an experiment. If posterior distribution same whatever order which pooling and updating are done, mechanism said be externally Bayesian by Madansky (1964). In this paper, we characterize all formulas give conditions under opinion will proportional geometric average individual densities.
Abstract Suppose a decision maker has asked group of experts to assess subjective probability distributions over some space, and he wishes find consensus distribution as function these. The assumption that finding the commutes with marginalization implies must be found using linear opinion pool (weighted average), provided space being considered contains three or more points. Some consequences this result are discussed. Key Words: Opinion poolMarginalizationConsensusSubjective...
How should statisticians interact with journalists? The author, an academic statistician, has worked journalists in several ways over the years. article explores many-sided relationship between scientists, and public, from point of view involved. One pessimistic role numbers news is that they are there largely for rhetorical reasons, to increase credibility authority a story. author would not subscribe view, but it does potential need educate readers as well dealing numbers, briefly...
Variations in the origination and extinction rates of species over geological time often are linked with a range factors, including evolution key innovations, changes ecosystem structure, environmental factors such as shifts climate physical geography. Before hypothesizing causality single factor, it is critical to demonstrate that observed variation diversification significantly greater than one would expect due natural stochasticity evolutionary branching process. Here, we use...
Summary The growing literature on the phylogenetic structure of plant communities places great emphasis role niche conservatism ( PNC ) in community assembly. However, patterns revealed by such analyses are difficult to interpret absence independent data structure. While there is increasing evidence that coexistence does depend upon differences, it still not clear most cases what relevant axes are. We address this problem testing for within A frican R estionaceae (‘restios’), a clade endemic...
The Park Grass Experiment (PGE) is the longest‐observed set of experimental plant communities in existence. Although gross composition vegetation was at equilibrium over 60‐yr period from 1920 to 1979, annual records show that individual species exhibited a range dynamics. We tested two hypotheses explain why some initially increased and subsequently these (the outbreak species) decreased again. study designed around eight phylogenetically independent contrasts (PICs), each containing...