the gale encyclopedia of science

Department of Embryology, Obstetrics, andGynecology University of BolognaBologna, Italy Clayton Harris Associate ProfessorDepartment of Geography and GeologyMiddle Tennessee State Univer

The GALE ENCYCLOPEDIA

THIRD EDITION

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The GALE ENCYCLOPEDIA

A ardvark - Chaos

Gale Encyclopedia of Science, Third Edition

K Lee Lerner and Brenda Wilmoth Lerner, Editors

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Kimberley A McGrath

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LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA

Gale encyclopedia of science / K Lee Lerner & Brenda Wilmoth Lerner, editors.— 3rd ed.

p cm.

Includes index.

ISBN 0-7876-7554-7 (set) — ISBN 0-7876-7555-5 (v 1) — ISBN 0-7876-7556-3 (v 2) — ISBN 0-7876-7557-1 (v 3) — ISBN 0-7876-7558-X (v 4) — ISBN 0-7876-7559-8 (v 5) — ISBN 0-7876-7560-1 (v 6)

1 Science—Encyclopedias I Lerner, K Lee II Lerner, Brenda Wilmoth.

Q121.G37 2004

Topic List vii

Organization of the Encyclopedia xxvii

Advisory Board xxix

Contributors xxxi

Entries Volume 1 (Aardvark–Chaos) 1–818 Volume 2 (Charge-coupled device–Eye) 819–1572 Volume 3 (Factor–Kuru) 1573–2254 Volume 4 (Lacewings–Pharmacogenetics) 2255–3036 Volume 5 (Pheasants–Star) 3037–3800 Volume 6 (Star cluster–Zooplankton) 3801–4378

General Index 4379–4495

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AluminumAluminum hydroxideAlzheimer diseaseAmaranth family (Amaranthaceae)Amaryllis family (Amaryllidaceae)American Standard Code forInformation InterchangeAmes test

Amicable numbersAmides

Amino acidAmmoniaAmmonificationAmnesiaAmniocentesisAmoebaAmphetaminesAmphibiansAmplifierAmputationAnabolismAnaerobicAnalemmaAnalgesiaAnalog signals and digital signalsAnalytic geometry

AnaphylaxisAnatomyAnatomy, comparativeAnchovy

Anemia

AdrenalsAerobicAerodynamicsAerosolsAfricaAge of the universeAgent OrangeAging and deathAgouti

Agricultural machinesAgrochemicalsAgronomyAIDSAIDS therapies and vaccinesAir masses and frontsAir pollution

AircraftAirshipAlbatrossesAlbedoAlbinismAlchemyAlcoholAlcoholismAldehydesAlgaeAlgebraAlgorithmAlkali metalsAlkaline earth metalsAlkaloid

Alkyl groupAllelesAllergyAllotropeAlloy

TOPIC LIST

Atomic modelsAtomic numberAtomic spectroscopyAtomic theoryAtomic weightAtomsAttention-deficit/Hyperactivitydisorder (ADHD)

AuksAustraliaAutismAutoimmune disordersAutomatic pilotAutomationAutomobileAutotrophAvogadro’s numberAye-ayes

B

BabblersBaboonsBacteriaBacteriophageBadgersBall bearingBallistic missilesBallisticsBalloonBananaBandicootsBar codeBarberryBarbetsBarbituratesBariatricsBariumBarium sulfateBark

BarleyBarnaclesBarometerBarracuda

ArcARC LAMPArchaebacteriaArchaeoastronomyArchaeogeneticsArchaeologyArchaeometallurgyArchaeometryArcheological mappingArcheological sitesArithmeticArmadillosArrow wormsArrowgrassArrowrootArteriesArteriosclerosisArthritisArthropodsArthroscopic surgeryArtifacts and artifact classificationArtificial fibers

Artificial heart and heart valveArtificial intelligence

Artificial visionArum family (Araceae)Asbestos

Asexual reproductionAsia

Assembly lineAsses

Associative propertyAsteroid 2002AA29AsthenosphereAsthmaAstrobiologyAstroblemesAstrolabeAstrometryAstronomical unitAstronomyAstrophysicsAtmosphere, composition andstructure

Atmosphere observation Atmospheric circulationAtmospheric optical phenomenaAtmospheric pressure

Brown dwarfBrownian motionBrucellosisBryophyteBubonic plagueBuckminsterfullereneBuckthorn

BuckwheatBuds and buddingBuffer

Building design/architectureBulbuls

Bunsen burnerBuoyancy, principle ofBuret

BurnBustardsButtercupButterfliesButterfly fishButyl groupButylated hydroxyanisoleButylated hydroxytolueneBuzzards

C

CactusCAD/CAM/CIMCaddisfliesCaeciliansCaffeineCaissonCalciumCalcium carbonateCalcium oxideCalcium propionateCalcium sulfateCalculatorCalculusCalendars

BioremediationBiosphereBiosphere ProjectBiotechnologyBioterrorismBirch family (Betulaceae)Birds

Birds of paradiseBirds of preyBirthBirth defectsBisonBitternsBivalves

BL Lacertae objectBlack holeBlackbirdsBlackbody radiationBleach

BlenniesBlindness and visual impairmentsBlindsnakes

BloodBlood gas analysisBlood supplyBlotting analysisBlue revolution (aquaculture)Bluebirds

BoarfishBoasBohr ModelBoiling pointBond energyBony fishBoobies and gannetsBoolean algebraBoric acidBotanyBotulismBowen’s reaction seriesBowerbirds

BowfinBoxfishBrachiopodsBrackishBrainBrewingBrick

ChlorineChlorofluorocarbons (CFCs)Chloroform

ChlorophyllChloroplastCholeraCholesterolChordatesChorionic villus sampling (CVS)Chromatin

ChromatographyChromosomal abnormalitiesChromosome

Chromosome mappingCicadas

Cigarette smokeCircle

Circulatory systemCircumscribed and inscribedCirrhosis

Citric acidCitrus treesCivetsClimax (ecological)Clingfish

Clone and cloningClosed curvesClosure propertyClouds

Club mossesCoalCoast and beachCoatis

CocaCocaineCockatoosCockroachesCodeineCodfishesCodonsCoefficientCoelacanth

CatfishCathetersCathodeCathode ray tubeCation

CatsCattailsCattle family (Bovidae)Cauterization

CaveCave fishCelestial coordinatesCelestial mechanicsCelestial sphere: The apparentmotions of the Sun, Moon,planets, and stars

CellCell deathCell divisionCell, electrochemical Cell membrane transportCell staining

Cellular respirationCellular telephoneCellulose

CentipedesCentrifugeCeramicsCerenkov effectCetaceansChachalacasChameleonsChaosCharge-coupled deviceChelate

Chemical bondChemical evolutionChemical oxygen demandChemical reactionsChemical warfareChemistryChemoreceptionChestnutChi-square testChickenpoxChildhood diseasesChimaeras

Chimpanzees

CrystalCubic equationsCuckoosCurareCurlewsCurrentsCurveCushing syndromeCuttlefish

CyberneticsCycadsCyclamateCyclone and anticycloneCyclosporine

CyclotronCystic fibrosisCytochromeCytology

D

DamsDamselfliesDark matterDating techniquesDDT (Dichlorodiphenyl-trichloroacetic acid)Deafness and inherited hearing lossDecimal fraction

DecompositionDeer

Deer mouseDeforestationDegreeDehydroepiandrosterone (DHEA)Delta

DementiaDengue feverDenitrification

ConstellationConstructionsContaminated soilContaminationContinentContinental driftContinental marginContinental shelfContinuityContour plowingContraceptionConvectionCoordination compoundCopepods

CopperCoral and coral reefCoriolis effectCork

CormCormorantsCorn (maize)Coronal ejections and magneticstorms

Correlation (geology)Correlation (mathematics)Corrosion

Cosmic background radiationCosmic ray

CosmologyCotingasCottonCoulombCountableCoursers and pratincolesCourtship

CoypuCrabsCraneCranesCrayfishCrestfishCreutzfeldt-Jakob diseaseCrickets

Critical habitatCrocodilesCrop rotationCropsCross multiply

EcosystemEcotoneEcotourismEdemaEel grass

El Niño and La NiñaEland

Elapid snakesElasticityElectric arcElectric chargeElectric circuitElectric conductorElectric currentElectric motorElectric vehiclesElectrical conductivityElectrical power supplyElectrical resistanceElectricity

Electrocardiogram (ECG)Electroencephalogram (EEG)Electrolysis

ElectrolyteElectromagnetic fieldElectromagnetic inductionElectromagnetic spectrumElectromagnetismElectromotive forceElectron

Electron cloudElectronicsElectrophoresisElectrostatic devicesElement, chemicalElement, families ofElement, transuraniumElements, formation ofElephant

Elephant shrews

DobsonfliesDogwood treeDomainDonkeysDopamineDoppler effectDoriesDormouseDouble-blind studyDouble helix Down syndromeDragonfliesDrift netDrongos

Drosophila melanogaster

DroughtDucksDuckweedDuikersDuneDuplication of the cubeDust devil

DVDDwarf antelopesDyes and pigmentsDysentery

DyslexiaDysplasiaDystrophinopathies

E

e (number)EaglesEarEarthEarth scienceEarth’s interiorEarth’s magnetic fieldEarth’s rotationEarthquakeEarwigsEating disordersEbola virusEbonyEchiuroid worms

Elephant snout fish

Figurative numbersFiltration

FinchesFirsFishFlagellaFlame analysisFlamingosFlatfishFlatwormsFlaxFleasFliesFlightless birdsFloodingFloraFlowerFluid dynamicsFluid mechanicsFluorescenceFluorescence in situ hybridization(FISH)

Fluorescent lightFluoridationFlying fishFocused Ion Beam (FIB)Fog

FoldFood chain/webFood irradiationFood poisoningFood preservationFood pyramidFoot and mouth diseaseForce

Forensic scienceForestryForestsFormula, chemical

EthnoarchaeologyEthnobotanyEthyl groupEthylene glycolEthylenediaminetetra-acetic acidEtiology

EubacteriaEugenicsEukaryotaeEuropeEutrophicationEvaporationEvapotranspirationEven and oddEvent horizonEvolutionEvolution, convergentEvolution, divergentEvolution, evidence ofEvolution, parallelEvolutionary change, rate ofEvolutionary mechanismsExcavation methodsExclusion principle, PauliExcretory systemExercise

Exocrine glandsExplosivesExponentExtinctionExtrasolar planetsEye

F

FactorFactorialFalconsFaraday effectFat

Fatty acidsFaultFaunaFax machineFeather starsFermentation

Grand unified theoryGrapes

Graphs and graphingGrasses

GrasshoppersGrasslandsGravitational lensGravity and gravitationGreat Barrier ReefGreatest common factorGrebes

Greenhouse effectGroundhogGroundwaterGroupGrouseGrowth and decayGrowth hormonesGuenons

Guillain-Barre syndromeGuinea fowl

Guinea pigs and caviesGulls

GuppyGutenberg discontinuityGutta percha

GymnospermGynecologyGyroscope

H

HabitatHagfishHalf-lifeHalide, organicHall effect

Genetic disordersGenetic engineeringGenetic identification ofmicroorganismsGenetic testingGenetically modified foods andorganisms

GeneticsGenetsGenomeGenomics (comparative)Genotype and phenotypeGeocentric theoryGeochemical analysisGeochemistryGeodeGeodesicGeodesic domeGeographic and magnetic polesGeologic map

Geologic timeGeologyGeometryGeomicrobiologyGeophysicsGeotropismGerbilsGerm cells and the germ cell lineGerm theory

GerminationGerontologyGesneriasGeyserGibbons and siamangsGila monster

GingerGinkgoGinsengGiraffes and okapiGIS

GlaciersGlandsGlassGlobal climateGlobal Positioning SystemGlobal warming

GlycerolGlycol

IbisesIceIce age refugesIce agesIcebergsIcemanIdentity elementIdentity propertyIgneous rocksIguanasImaginary numberImmune systemImmunologyImpact craterImprinting

In vitro fertilization (IVF)

In vitro and in vivo

Incandescent lightIncinerationIndicator, acid-base Indicator speciesIndividualIndoor air qualityIndustrial mineralsIndustrial RevolutionInequality

Inertial guidanceInfectionInfertilityInfinityInflammationInflection pointInfluenzaInfrared astronomyInherited disordersInsecticidesInsectivore

HistamineHistorical geologyHoatzin

Hodgkin’s diseaseHolly family (Aquifoliaceae)Hologram and holographyHomeostasis

HoneycreepersHoneyeatersHoopoeHorizonHormonesHornbillsHorse chestnutHorsehair wormsHorses

Horseshoe crabsHorsetailsHorticultureHot spotHovercraftHubble Space TelescopeHuman artificial chromosomesHuman chorionic gonadotropinHuman cloning

Human ecologyHuman evolutionHuman Genome ProjectHumidity

HummingbirdsHumusHuntington diseaseHybrid

HydraHydrocarbonHydrocephalusHydrochlorofluorocarbonsHydrofoil

HydrogenHydrogen chlorideHydrogen peroxideHydrogenationHydrologic cycleHydrologyHydrolysisHydroponicsHydrosphereHydrothermal vents

Internal combustion engine

International Space Station

International Ultraviolet Explorer

Internet file transfer and tracking

Internet and the World Wide Web

LEDLegionnaires’ diseaseLegumes

LemmingsLemursLensLeprosyLeukemiaLewis structureLice

LichensLife historyLigandLightLight-yearLightningLilacLily family (Liliaceae)Limit

Limiting factorLimpetsLine, equations ofLinear algebraLipid

Liquid crystalsLithiumLithographyLithosphereLithotripsyLiverwortLivestockLobstersLockLock and keyLocusLogarithmsLoonsLORAN

Jet streamJuniperJupiter

K

K-T event (Cretaceous-Tertiaryevent)

Kangaroo ratsKangaroos and wallabiesKarst topographyKaryotype and karyotype analysisKelp forests

Kepler’s lawsKeystone speciesKillifish

KingfishersKingletsKoalasKolaKorsakoff’s syndromeKrebs cycle

Kuiper belt objectsKuru

L

LacewingsLactic acidLagomorphsLakeLamarckismLampreys and hagfishesLand and sea breezesLand use

LandfillLandformLangurs and leaf monkeysLantern fish

LanthanidesLarksLaryngitisLaserLaser surgeryLatitude and longitude

MildewMilkweedsMilky WayMiller-Urey ExperimentMillipedes

MimicryMineralogyMineralsMiningMinkMinnowsMinor planetsMint familyMir Space StationMirrors

MiscibilityMistletoeMitesMitosisMixture, chemicalMöbius stripMockingbirds and thrashersMode

Modular arithmeticMohs’ scaleMoldMoleMole-ratsMolecular biologyMolecular formulaMolecular geometryMolecular weightMoleculeMolesMollusksMomentumMonarch flycatchersMongooses

Monitor lizardsMonkeys

MarsupialsMarten, sable, and fisherMaser

MassMass extinctionMass numberMass productionMass spectrometryMass transportationMass wastingMathematicsMatrixMatterMaunder minimumMaxima and minimaMayflies

MeanMedianMedical geneticsMeiosis

MembraneMemoryMendelian geneticsMeningitis

MenopauseMenstrual cycleMercurous chlorideMercury (element)Mercury (planet)Mesoscopic systemsMesozoa

Metabolic disordersMetabolismMetalMetal fatigueMetal productionMetallurgyMetamorphic gradeMetamorphic rockMetamorphismMetamorphosisMeteorologyMeteors and meteoritesMethyl group

Metric systemMice

Michelson-Morley experimentMicrobial genetics

Mulberry family (Moraceae)

Multiple personality disorder

Number theoryNumeration systemsNut

NuthatchesNutmegNutrient deficiency diseasesNutrients

NutritionNux vomica tree

O

OaksObesityObsessionOceanOcean basinOcean sunfishOcean zonesOceanographyOctet ruleOctopusOhm’s lawOil spillsOil well drillingOld-growth forestsOlive family (Oleaceae)Omnivore

One-to-one correspondenceOpah

Open-source softwareOpossums

Opportunistic speciesOptical data storageOptics

Orang-utanOrbitOrchid familyOrdinal numberOre

OrganOrganelles and subcellular genetics

Natural gasNatural numbersNautical archaeologyNEAR-Earth Object Hazard IndexNectar

NegativeNeptuneNerve growth factorNerve impulses and conduction ofimpulses

Nervous systemNeuromuscular diseasesNeuron

NeuroscienceNeurosurgeryNeurotransmitterNeutralizationNeutrinoNeutronNeutron activation analysisNeutron star

New World monkeysNewton’s laws of motionNewts

NicheNicotineNight vision enhancement devicesNightshade

Nitric acidNitrificationNitrogenNitrogen cycleNitrogen fixationNoise pollutionNon-Euclidean geometryNon-point sourceNonmetalNorth AmericaNova

NovocainNuclear fissionNuclear fusionNuclear magnetic resonanceNuclear medicine

Nuclear powerNuclear reactorNuclear weaponsNuclear winter

PhotochemistryPhotocopyingPhotoelectric cellPhotoelectric effectPhotographyPhotography, electronicPhoton

PhotosynthesisPhototropismPhotovoltaic cellPhylogenyPhysical therapyPhysics

PhysiologyPhysiology, comparativePhytoplankton

PiPigeons and dovesPigs

PikePiltdown hoaxPinecone fishPinesPipefishPlaceboPlanck’s constantPlane

Plane familyPlanetPlanet XPlanetary atmospheresPlanetary geologyPlanetary nebulaePlanetary ring systems

PandasPangolinsPapayaPaperParabolaParallaxParallelParallelogramParasitesParityParkinson diseaseParrots

ParthenogenesisParticle detectorsPartridgesPascal’s trianglePassion flowerPaternity and parentage testingPathogens

PathologyPCRPeafowlPeanut wormsPeccariesPedigree analysisPelicans

PenguinsPeninsulaPentyl groupPeonyPepperPeptide linkagePercentPerceptionPerchPeregrine falconPerfect numbersPeriodic functionsPeriodic tablePermafrostPerpendicularPesticidesPestsPetrels and shearwatersPetroglyphs and pictographsPetroleum

pHPhalangers

Potassium aluminum sulfate

Potassium hydrogen tartrate

Quantum numberQuarks

QuasarQuetzalQuinine

R

RabiesRaccoonsRadarRadial keratotomyRadiation

Radiation detectorsRadiation exposureRadical (atomic)Radical (math)Radio

Radio astronomyRadio wavesRadioactive datingRadioactive decayRadioactive falloutRadioactive pollutionRadioactive tracersRadioactive wasteRadioisotopes in medicineRadiology

RadonRailsRainbowsRainforestRandomRangelandRaptorsRare gasesRare genotype advantage

Prairie dogPrairie falconPraying mantisPrecession of the equinoxesPrecious metals

PrecipitationPredatorPrenatal surgeryPrescribed burnPressurePreyPrimatesPrime numbersPrimrosesPrintingPrionsPrismProbability theoryProboscis monkeyProjective geometryProkaryote

PronghornProofPropyl groupProsimiansProstheticsProteasProtected areaProteinsProteomicsProtistaProtonProtozoaPsychiatryPsychoanalysisPsychologyPsychometryPsychosisPsychosurgeryPubertyPuffbirdsPuffer fishPulsarPunctuated equilibriumPyramid

Pythagorean theoremPythons

SealsSeamountsSeasonal windsSeasonsSecondary pollutantsSecretary birdSedgesSediment and sedimentationSedimentary environmentSedimentary rockSeed fernsSeedsSegmented wormsSeismographSelectionSequencesSequencingSequoiaServomechanismsSesame

Set theorySETISevere acute respiratory syndrome(SARS)

Sewage treatmentSewing machineSex changeSextant

Ribonucleic acid (RNA)Ribosomes

RiceRicinRickettsiaRiversRNA functionRNA splicingRobinsRoboticsRockets and missilesRocks

RodentsRollersRoot systemRose family (Rosaceae)Rotation

RoundwormsRuminationRushesRusts and smuts

S

Saiga antelopeSalamandersSalmonSalmonellaSaltSaltwaterSampleSandSand dollarsSandfishSandpipersSapodilla treeSardinesSarin gasSatelliteSaturnSavannaSavantSawfishSaxifrage familyScalar

Scale insects

StarStar clusterStar formationStarburst galaxyStarfish

StarlingsStates of matterStatistical mechanicsStatistics

Steady-state theorySteam engineSteam pressure sterilizerStearic acid

SteelStellar evolutionStellar magnetic fieldsStellar magnitudesStellar populationsStellar structureStellar windStem cellsStereochemistrySticklebacksStilts and avocetsStimulus

Stone and masonryStoneflies

StorksStormStorm surgeStrataStratigraphyStratigraphy (archeology)Stream capacity and competenceStream valleys, channels, andfloodplains

StrepsipteraStressStress, ecologicalString theory

Solar activity cycleSolar flare

Solar illumination: Seasonal anddiurnal patterns

Solar prominenceSolar systemSolar windSolder and soldering ironSolstice

SolubilitySolutionSolution of equationSonar

Song birdsSonoluminescenceSorghum

Sound wavesSouth AmericaSoybeanSpaceSpace probeSpace shuttleSpacecraft, mannedSparrows and buntingsSpecies

Spectral classification of starsSpectral lines

SpectroscopeSpectroscopySpectrumSpeechSphereSpider monkeysSpiderwort familySpin of subatomic particlesSpina bifida

SpinachSpiny anteatersSpiny eelsSpiny-headed wormsSpiral

SpirometerSplit-brain functioningSponges

Spontaneous generationSpore

SpringtailsSpruce

Swallows and martins

Swamp cypress family

TouchTowers of HanoiToxic shock syndromeToxicology

Trace elementsTragopansTrains and railroadsTranquilizersTranscendental numbersTransducer

TransformerTransgenicsTransistorTransitiveTranslationsTranspirationTransplant, surgicalTrapezoid

TreeTree shrewsTrichinosisTriggerfishTriglyceridesTrigonometryTritiumTrogonsTrophic levelsTropic birdsTropical cycloneTropical diseasesTrout-perchTrue bugs

T

T cellsTanagersTaphonomyTapirsTarponsTarsiersTartaric acidTasmanian devilTaste

TaxonomyTay-Sachs diseaseTea plant

TectonicsTelegraphTelemetryTelephoneTelescopeTelevisionTemperatureTemperature regulationTenrecs

TeratogenTermTermitesTernsTerracingTerritorialityTetanusTetrahedronTextilesThalidomideTheoremThermal expansionThermochemistryThermocoupleThermodynamicsThermometerThermostatThistleThoracic surgeryThrips

ThrombosisThrushesThunderstormTides

Weaver finchesWeevilsWeldingWest Nile virusWetlandsWheatWhisk fernWhite dwarfWhite-eyesWhooping coughWild typeWildfireWildlifeWildlife trade (illegal)Willow family (Salicaceae)Wind

Wind chillWind shearWintergreenWolverineWombatsWoodWoodpeckersWoolly mammothWork

VacuumVacuum tubeValenceVan Allen beltsVan der Waals forcesVapor pressureVariableVariable starsVarianceVaricella zoster virusVariola virusVegetablesVeinsVelocityVenusVerbena family (Verbenaceae)Vertebrates

Video recordingViolet family (Violaceae)Vipers

Viral geneticsVireosVirtual particlesVirtual realityVirus

ViscosityVisionVision disordersVitaminViviparityVivisectionVolatilityVolcanoVolesVolumeVoyager spacecraftVulcanizationVultures

VX agent

W

Wagtails and pipitsWalkingsticksWalnut familyWalruses

Y2KYakYamYeastYellow feverYewYttrium

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The Gale Encyclopedia of Science, Third Edition

has been designed with ease of use and ready reference

in mind

• Entries are alphabetically arranged across six volumes,

in a single sequence, rather than by scientific field

• Length of entries varies from short definitions of one or

two paragraphs, to longer, more detailed entries on

more complex subjects

• Longer entries are arranged so that an overview of the

subject appears first, followed by a detailed discussion

conveniently arranged under subheadings

• A list of key terms is provided where appropriate to

de-fine unfamiliar terms or concepts

• Bold-faced terms direct the reader to related articles

• Longer entries conclude with a “Resources” section,

which points readers to other helpful materials

(includ-ing books, periodicals, and Web sites)

• The author’s name appears at the end of longer entries.His or her affiliation can be found in the “Contributors”section at the front of each volume

• “See also” references appear at the end of entries topoint readers to related entries

• Cross references placed throughout the encyclopediadirect readers to where information on subjects withouttheir own entries can be found

• A comprehensive, two-level General Index guidesreaders to all topics, illustrations, tables, and personsmentioned in the book

AVAILABLE IN ELECTRONIC FORMATS

Licensing The Gale Encyclopedia of Science, Third

Edition is available for licensing The complete database

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ORGANIZATION OF THE ENCYCLOPEDIA

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ACADEMIC ADVISORS

Marcelo Amar, M.D.

Senior Fellow, Molecular Disease Branch

National Institutes of Health (NIH)

University of South Carolina School of Medicine

Columbia, South Carolina

William J Engle P.E

Exxon-Mobil Oil Corporation (Rt.) New Orleans, Louisiana

Bill Freedman

ProfessorDepartment of Biology and School for Resource andEnvironmental Studies

Dalhousie UniversityHalifax, Nova Scotia, Canada

Antonio Farina, M.D., Ph.D

Department of Embryology, Obstetrics, andGynecology

University of BolognaBologna, Italy

Clayton Harris

Associate ProfessorDepartment of Geography and GeologyMiddle Tennessee State UniversityMurfreesboro, Tennesses

encyclo-The University of Western Australia

Molecular Oncology and Development

Program/Boyer Center for Molecular Medicine

Yale University School of Medicine

New Haven, Connecticut

William S Pretzer

Curator

Henry Ford Museum and Greenfield Village

Dearborn, Michigan

Judyth Sassoon, Ph.D., ARCS

Department of Biology and Biochemistry

Michael J Sullivan, M.D., Ph.D., FRACP

Cancer Genetics LaboratoryUniversity of Otago

Dunedin, New Zealand

Richard Addison Wood

Meteorological ConsultantTucson, Arizona

Diego F Wyszynski, M.D., Ph.D

Department of Medicine, Epidemiology &

BiostatisticsBoston University School of MedicineBoston, Massachusetts

Rashmi Venkateswaran

Undergraduate Lab CoordinatorDepartment of ChemistryUniversity of OttawaOttawa, Ontario, Canada

LIBRARIAN ADVISORS

Donna Miller

DirectorCraig-Moffet County LibraryCraig, Colorado

Judy Williams

Media CenterGreenwich High SchoolGreenwich, Connecticut

Nasrine Adibe

Professor Emeritus

Department of Education

Long Island University

Westbury, New York

Georgia Southern UniversityStatesboro, Georgia

Carolyn Black

ProfessorIncarnate Word CollegeSan Antonio, Texas

Larry Blaser

Science WriterLebanon, Tennessee

Jean F Blashfield

Science WriterWalworth, Wisconsin

Richard L Branham Jr

DirectorCentro Rigional deInvestigaciones Científicas yTecnológicas

Mendoza, Argentina

Patricia Braus

EditorAmerican DemographicsRochester, New York

Dana M Barry

Editor and Technical WriterCenter for Advanced MaterialsProcessing

Clarkston UniversityPotsdam, New York

Puja Batra

Department of ZoologyMichigan State UniversityEast Lansing, Michigan

Donald Beaty

Professor EmeritusCollege of San MateoSan Mateo, California

Eugene C Beckham

Department of Mathematics andScience

Northwood InstituteMidland, Michigan

Martin Beech

Research AssociateDepartment of AstronomyUniversity of Western OntarioLondon, Ontario, Canada

Julie Berwald, Ph.D (Ocean Sciences)

Austin, Texas

Massimo D Bezoari

Associate ProfessorDepartment of ChemistryHuntingdon CollegeMontgomery, Alabama

John M Bishop III

TranslatorNew York, New York

CONTRIBUTORS

Brandon R Brown

Graduate Research Assistant

Oregon State University

Toronto, Ontario, Canada

Scott Christian Cahall

Center for Quantum Mechanics

The University of Texas at Dallas

Physician and Medical Writer

Durham, North Carolina

Mary Ann Cunningham

Environmental Writer

St Paul, Minnesota

Les C Cwynar

Associate ProfessorDepartment of BiologyUniversity of New BrunswickFredericton, New Brunswick

Paul Cypher

Provisional InterpreterLake Erie MetroparkTrenton, Michigan

Stanley J Czyzak

Professor EmeritusOhio State UniversityColumbus, Ohio

Rosi Dagit

Conservation BiologistTopanga-Las Virgenes ResourceConservation District

Topanga, California

David Dalby

PresidentBruce Tool Company, Inc.Taylors, South Carolina

Lou D’Amore

Chemistry TeacherFather Redmund High SchoolToronto, Ontario, Canada

Douglas Darnowski

Postdoctoral FellowDepartment of Plant BiologyCornell University

Ithaca, New York

Sreela Datta

Associate WriterAztec PublicationsNorthville, Michigan

Sarah K Dean

Science WriterPhiladelphia, Pennsylvania

Kenneth B Chiacchia

Medical EditorUniversity of Pittsburgh MedicalCenter

Pittsburgh, Pennsylvania

M L Cohen

Science WriterChicago, Illinois

Robert Cohen

ReporterKPFA Radio NewsBerkeley, California

Sally Cole-Misch

Assistant DirectorInternational Joint CommissionDetroit, Michigan

George W Collins II

Professor EmeritusCase Western ReserveChesterland, Ohio

Jeffrey R Corney

Science WriterThermopolis, Wyoming

Tom Crawford

Assistant DirectorDivision of Publication andDevelopment

University of Pittsburgh MedicalCenter

Edward Cruetz

PhysicistRancho Santa Fe, California

Frederick Culp

ChairmanDepartment of PhysicsTennessee TechnicalCookeville, Tennessee

New York University

New York, New York

New York University

New York, New York

Bill Freedman

ProfessorDepartment of Biology andSchool for Resource andEnvironmental StudiesDalhousie UniversityHalifax, Nova Scotia

T A Freeman

Consulting ArchaeologistQuail Valley, California

Elaine Friebele

Science WriterCheverly, Maryland

Randall Frost

Documentation EngineeringPleasanton, California

Agnes Galambosi, M.S.

ClimatologistEotvos Lorand UniversityBudapest, Hungary

Larry Gilman, Ph.D (Electrical Engineering)

EngineerSharon, Vermont

Kathryn Glynn

AudiologistPortland, Oregon

David Goings, Ph.D (Geology)

GeologistLas Vegas, Nevada

Natalie Goldstein

Educational EnvironmentalWriting

Phoenicia, New York

Bernice Essenfeld

Biology WriterWarren, New Jersey

Mary Eubanks

Instructor of BiologyThe North Carolina School ofScience and MathematicsDurham, North Carolina

Kathryn M C Evans

Science WriterMadison, Wisconsin

William G Fastie

Department of Astronomy andPhysics

Bloomberg CenterBaltimore, Maryland

Barbara Finkelstein

Science WriterRiverdale, New York

Sara G B Fishman

ProfessorQuinsigamond CommunityCollege

Worcester, Massachusetts

David Fontes

Senior InstructorLloyd Center for EnvironmentalStudies

Westport, Maryland

Barry Wayne Fox

Extension Specialist,Marine/Aquatic EducationVirginia State UniversityPetersburg, Virginia

Ed Fox

Charlotte Latin SchoolCharlotte, North Carolina

South Granville High School

Durham, North Carolina

Hans G Graetzer

Professor

Department of Physics

South Dakota State University

Brookings, South Dakota

University of Rhode Island

Leonard Darr Holmes

Department of Physical SciencePembroke State UniversityPembroke, North Carolina

Rita Hoots

Instructor of Biology, Anatomy,Chemistry

Yuba CollegeWoodland, California

Zafer Iqbal

Allied Signal Inc

Morristown, New Jersey

Sophie Jakowska

Pathobiologist, EnvironmentalEducator

Santo Domingo, DominicanRepublic

Richard A Jeryan

Senior Technical SpecialistFord Motor CompanyDearborn, Michigan

Stephen R Johnson

Biology WriterRichmond, Virginia

Kathleen A Jones

School of MedicineSouthern Illinois UniversityCarbondale, Illinois

Harold M Kaplan

ProfessorSchool of MedicineSouthern Illinois UniversityCarbondale, Illinois

Anthony Kelly

Science WriterPittsburgh, Pennsylvania

Lawrence Hammar, Ph.D.

Senior Research FellowInstitute of Medical ResearchPapua, New Guinea

William Haneberg, Ph.D.

(Geology)

GeologistPortland, Oregon

Beth Hanson

Editor

The Amicus Journal

Brooklyn, New York

Clay Harris

Associate ProfessorDepartment of Geography andGeology

Middle Tennessee StateUniversity

Pella, Iowa

Dean Allen Haycock

Science WriterSalem, New York

Paul A Heckert

ProfessorDepartment of Chemistry andPhysics

Western Carolina UniversityCullowhee, North Carolina

Darrel B Hoff

Department of PhysicsLuther College Calmar, Iowa

Dennis Holley

Science EducatorShelton, Nebraska

Amy Kenyon-Campbell

Ecology, Evolution and

Organismal Biology Program

Los Alamos National Laboratory

Los Alamos, New Mexico

Associate News Editor

Journal of Cell Biology

New York, New York

J R Maddocks

Consulting ScientistDeSoto, Texas

Gail B C Marsella

Technical WriterAllentown, Pennsylvania

Karen Marshall

Research AssociateCouncil of State Governmentsand Centers for Environmentand Safety

Lexington, Kentucky

Liz Marshall

Science WriterColumbus, Ohio

James Marti

Research ScientistDepartment of MechanicalEngineering

University of MinnesotaMinneapolis, Minnesota

Elaine L Martin

Science WriterPensacola, Florida

Lilyan Mastrolla

Professor EmeritusSan Juan Unified SchoolSacramento, California

Iain A McIntyre

ManagerElectro-optic DepartmentEnergy Compression ResearchCorporation

Vista, California

Jennifer L McGrath

Chemistry TeacherNorthwood High SchoolNappanee, Indiana

San Diego, California

Adrienne Wilmoth Lerner

Graduate School of Arts &

Science Vanderbilt UniversityNashville, Tennessee

Lee Wilmoth Lerner

Science WriterNASA

Kennedy Space Center, Florida

Scott Lewis

Science WriterChicago, Illinois

Kristin Lewotsky

EditorLaser Focus WorldNashua, New Hamphire

Stephen K Lewotsky

ArchitectGrants Pass, Oregon

Agnieszka Lichanska, Ph.D

Department of Microbiology &

Parasitology University of QueenslandBrisbane, Australia

Sarah Lee Lippincott

Professor EmeritusSwarthmore CollegeSwarthmore, Pennsylvania

Jill Liske, M.Ed

Wilmington, North Carolina

David Lunney

Research ScientistCentre de SpectrométrieNucléaire et de Spectrométrie

de MasseOrsay, France

Christine Miner Minderovic

Nuclear Medicine Technologist

Franklin Medical Consulters

Ann Arbor, Michigan

Fingerlake Community College

Canandaigua, New York

Department of Systematic Botany

Institute of Biological Sciences

Borut Peterlin, M.D.

Consultant Clinical Geneticist,Neurologist, Head Division ofMedical Genetics

Department of Obstetrics andGynecology

University Medical CentreLjubljana

Ljubljana, Slovenia

John R Phillips

Department of ChemistryPurdue University, CalumetHammond, Indiana

Kay Marie Porterfield

Science WriterEnglewood, Colorado

Paul Poskozim

ChairDepartment of Chemistry, EarthScience and Physics

Northeastern Illinois UniversityChicago, Illinois

Patricia V Racenis

Science WriterLivonia, Michigan

Cynthia Twohy Ragni

Atmospheric ScientistNational Center for AtmosphericResearch

Westminster, Colorado

Jordan P Richman

Science WriterPhoenix, Arizona

Kitty Richman

Science WriterPhoenix, Arizona

Alfred UniversityAlfred, New York

Angie Mullig

Publication and DevelopmentUniversity of Pittsburgh MedicalCenter

Trafford, Pennsylvania

David R Murray

Senior AssociateSydney UniversitySydney, New South Wales,Australia

Sutharchana Murugan

ScientistThree Boehringer MannheimCorp

Indianapolis, Indiana

Muthena Naseri

Moorpark CollegeMoorpark, California

James O’Connell

Department of Physical SciencesFrederick Community CollegeGaithersburg, Maryland

Dúnal P O’Mathúna

Associate ProfessorMount Carmel College ofNursing

Royal Botanic Gardens

Edinburgh, Great Britain

Elena V Ryzhov

Polytechnic Institute

Troy, New York

David Sahnow

Associate Research Scientist

John Hopkins University

Baltimore, Maryland

Peter Salmansohn

Educational Consultant

New York State Parks

Cold Spring, New York

University of Colorado at BoulderBoulder, Colorado

John Spizzirri

Science WriterChicago, Illinois

Frieda A Stahl

Professor EmeritusDepartment of PhysicsCalifornia State University, LosAngeles

Los Angeles, California

Robert L Stearns

Department of PhysicsVassar CollegePoughkeepsie, New York

Ilana Steinhorn

Science WriterBoalsburg, Pennsylvania

University of TexasSan Antonio, Texas

Cheryl Taylor

Science EducatorKailua, Hawaii

Nicholas C Thomas

Department of Physical SciencesAuburn University at

MontgomeryMontgomery, Alabama

Randy Schueller

Science WriterChicago, Illinois

Kathleen Scogna

Science WriterBaltimore, Maryland

Anwar Yuna Shiekh

International Centre forTheoretical PhysicsTrieste, Italy

Raul A Simon

Chile Departmento de FísicaUniversidad de TarapacáArica, Chile

Michael G Slaughter

Science SpecialistIngham ISDEast Lansing, Michigan

Billy W Sloope

Professor EmeritusDepartment of PhysicsVirginia CommonwealthUniversity

Richmond, Virginia

Douglas Smith

Science WriterMilton, Massachusetts

Lesley L Smith

Department of Physics andAstronomy

University of KansasLawrence, Kansas

Kathryn D Snavely

Policy Analyst, Air Quality IssuesU.S General Accounting OfficeRaleigh, North Carolina

Iowa City, Iowa

Julia M Van Denack

West Carolina University

Cullowhee, North Carolina

Chester Vander Zee

Naturalist, Science Educator

Volga, South Dakota

Pella, Iowa

Frederick R West

AstronomerHanover, Pennsylvania

Glenn Whiteside

Science WriterWichita, Kansas

John C Whitmer

ProfessorDepartment of ChemistryWestern Washington UniversityBellingham, Washington

Donald H Williams

Department of ChemistryHope College

Holland, Michigan

Robert L Wolke

Professor EmeritusDepartment of ChemistryUniversity of PittsburghPittsburgh, Pennsylvania

Xiaomei Zhu, Ph.D.

Postdoctoral research associateImmunology DepartmentChicago Children’s MemorialHospital, NorthwesternUniversity Medical SchoolChicago, Illinois

Jim Zurasky

Optical PhysicistNichols Research CorporationHuntsville, Alabama

Rashmi Venkateswaran

Undergraduate Lab CoordinatorDepartment of ChemistryUniversity of OttawaOttawa, Ontario, Canada

R A Virkar

ChairDepartment of BiologicalSciences

Kean CollegeIselin, New Jersey

Kurt C Wagner

InstructorSouth Carolina Governor’sSchool for Science andTechnology

Hartsville, South Carolina

Cynthia Washam

Science WriterJensen Beach, Florida

Terry Watkins

Science WriterIndianapolis, Indiana

Joseph D Wassersug

PhysicianBoca Raton, Florida

Tom Watson

Environmental WriterSeattle, Washington

Aardvarks are nocturnal, secretive, termite- and

ant-eating mammals, and are one of Africa’s strangest

ani-mals Despite superficial appearances, aardvarks are not

classified as true anteaters; they have no close relatives

and are the only living species of the order Tubulidentata

and family Orycteropodidae Aardvarks are large piglikeanimals weighing from 88-143 lb (40-65 kg) and measur-ing nearly 6 ft (1.8 m) from nose to tip of tail They have

an arched body with a tapering piglike snout at one endand a long tapering tail at the other Their legs are power-ful and equipped with long, strong claws for digging The

A

An immature aardvark standing in the grass Photograph by Eric & David Hosking The National Audubon Society

Collection/Photo Researchers, Inc Reproduced by permission.