Relative species abundance
[1] For example, relative species abundances might describe all terrestrial birds in a forest community or all planktonic copepods in a particular marine environment.[12] Within the geometric series each species' level of abundance is a sequential, constant proportion (k) of the total number of individuals in the community.The geometric series rank-abundance diagram is linear with a slope of –k, and reflects a rapid decrease in species abundances by rank (Figure 4).[13] The geometric series model fits observed species abundances in highly uneven communities with low diversity.Using several data sets (including breeding bird surveys from New York and Pennsylvania and moth collections from Maine, Alberta and Saskatchewan) Frank W. Preston (1948) argued that species abundances (when binned logarithmically in a Preston plot) follow a normal (Gaussian) distribution, partly as a result of the central limit theorem (Figure 4).According to his argument, the right-skew observed in species abundance frequency histograms (including those described by Fisher et al. (1943)[14]) was, in fact, a sampling artifact.As the sample size increases Preston's veil is pushed farther to the left and more of the normal curve becomes visible[2][10](Figure 6).Williams' moth data, originally used by Fisher to develop the logseries distribution, became increasingly lognormal as more years of sampling were completed.[19] When the value of θ is small, the relative species abundance distribution is similar to the geometric series (high dominance).As θ gets larger, the distribution becomes increasingly s-shaped (log-normal) and, as it approaches infinity, the curve becomes flat (the community has infinite diversity and species abundances of one).[1] An unexpected result of the UNTB is that at very large sample sizes, predicted relative species abundance curves describe the metacommunity and become identical to Fisher's logseries.
biodiversityabundancesmacroecologyC.B. Williamstrophic levelplanktoniccopepodsCharles DarwinThe Origin of Speciesrank-abundance diagramsniche apportionment modelRonald FisherCarrington WilliamsAlexander Steven Corbetlogseries distributiondimensionlessFrank W. Prestonnormal (Gaussian) distributioncentral limit theoremlognormalGaussian formulaGalton–Watson modelgeneraniche apportionment modelsUnified neutral theory of biodiversityzero-summetacommunityBibcodeEcologyModelling ecosystemsTrophicAbiotic componentAbiotic stressBehaviourBiogeochemical cycleBiomassBiotic componentBiotic stressCarrying capacityCompetitionEcosystemEcosystem ecologyEcosystem modelGreen world hypothesisKeystone speciesList of feeding behavioursMetabolic theory of ecologyProductivityResourceRestorationProducersAutotrophsChemosynthesisChemotrophsFoundation speciesKinetotrophsMixotrophsMyco-heterotrophyMycotrophOrganotrophsPhotoheterotrophsPhotosynthesisPhotosynthetic efficiencyPhototrophsPrimary nutritional groupsPrimary productionConsumersApex predatorBacterivoreCarnivoresChemoorganotrophForagingGeneralist and specialist speciesIntraguild predationHerbivoresHeterotrophHeterotrophic nutritionInsectivoreMesopredatorsMesopredator release hypothesisOmnivoresOptimal foraging theoryPlanktivorePredationPrey switchingDecomposersChemoorganoheterotrophyDecompositionDetritivoresDetritusArchaeaBacteriophageLithoautotrophLithotrophyMarineMicrobial cooperationMicrobial ecologyMicrobial food webMicrobial intelligenceMicrobial loopMicrobial matMicrobial metabolismPhage ecologyFood websBiomagnificationEcological efficiencyEcological pyramidEnergy flowFood chainTritrophic interactions in plant defenseMarine food webscold seepsintertidalNorth Pacific Gyretide poolAscendencyBioaccumulationCascade effectClimax communityCompetitive exclusion principleConsumer–resource interactionsCopiotrophsDominanceEcological networkEcological successionEnergy quality