Global Ecol Biogeogr. 2019;28:315–327. wileyonlinelibrary.com/journal/geb  | 315© 2018 John Wiley & Sons Ltd

Received:7May2017  |  Revised:19September2018  |  Accepted:25September2018DOI: 10.1111/geb.12851

R E S E A R C H P A P E R

Body size, reef area and temperature predict global reef‐fish species richness across spatial scales

D. R. Barneche1,17  | E. L. Rezende2 | V. Parravicini3 | E. Maire6,7 |  G. J. Edgar8 | R. D. Stuart‐Smith8 | J. E. Arias‐González9 | C. E. L. Ferreira10 |  A. M. Friedlander11,12 | A. L. Green13 | O. J. Luiz14 | F. A. Rodríguez‐Zaragoza15 |  L. Vigliola16 | M. Kulbicki4,5 | S. R. Floeter17

1CollegeofLifeandEnvironmentalSciences,UniversityofExeter,PenrynTR109FE,UnitedKingdom2FacultaddeCienciasBiológicas,DepartamentodeEcología,CenterofAppliedEcologyandSustainability,PontificiaUniversidadCatólicadeChile,Santiago,Chile3ÉcolePratiquedesHautesEtudes,CRIOBE,USR3278CNRS‐EPHE‐UPVD,LabexCorail,UniversitédePerpignan,Perpignan,France4InstitutdeRecherchepourleDéveloppement,UMREntropie,LabexCorail,UniversitédePerpignan,Perpignan,France5CESAB‐FRB,ImmeubleHenriPoincaré,DomaineduPetitArbois,Aix‐en‐Provencecedex3,France6MARBEC,UMRIRD‐CNRS‐UM‐IFREMER9190,UniversitéMontpellier,MontpellierCedex,France7AustralianResearchCouncilCentreofExcellenceforCoralReefStudies,JamesCookUniversity,Townsville,QLD,Australia8InstituteforMarineandAntarcticStudies,UniversityofTasmania,Hobart,TAS,Australia9DepartamentodeRecursosdelMar,CentrodeInvestigaciónydeEstudiosAvanzadosdelInstitutoPolitécnicoNacional,Mérida,Mexico10DepartamentodeBiologiaMarinha,UniversidadeFederalFluminense,Niterói,Brazil11PristineSeas‐NationalGeographic,Washington,DistrictofColumbia12DepartmentofBiology,UniversityofHawaii,Honolulu,Hawaii13TheNatureConservancy,Brisbane,QLD,Australia14ResearchInstitutefortheEnvironmentandLivelihoods,CharlesDarwinUniversity,Darwin,NT,Australia15DepartamentodeEcología,CUCBA,UniversidaddeGuadalajara,Zapopan,México16InstitutdeRecherchepourleDéveloppement,UMREntropie,LabexLaboratoireExcellenceRécifsCoralliens,Noumea,France17MarineMacroecologyandBiogeographyLab,DepartamentodeEcologiaeZoologia,,UniversidadeFederaldeSantaCatarina,Florianópolis,Brazil

CorrespondenceD.R.Barneche,CollegeofLifeandEnvironmentalSciences,UniversityofExeter,PenrynTR109FE,UnitedKingdom.Email:barnechedr@gmail.com

Editor:CascadeSorte

AbstractAim:Toinvestigatebioticandabioticcorrelatesofreef‐fishspeciesrichnessacrossmultiplespatialscales.Location:Tropicalreefsaroundtheglobe,including485sitesin109sub‐provincesspreadacross14biogeographicprovinces.Time period:Present.Major taxa studied:2,523speciesofreeffish.Methods:Wecompiledadatabaseencompassing13,050visualtransects.WeusedhierarchicallinearBayesianmodelstoinvestigatewhetherfishbodysize,reefarea,isolation, temperature, andanthropogenic impacts correlatewith reef‐fish speciesrichnessateachspatialscale(i.e.,sites,sub‐provinces,provinces).Richnesswasesti‐matedusing coverage‐based rarefaction.Wealso testedwhether speciespacking(i.e.,transect‐levelspeciesrichness/m2)iscorrelatedwithprovince‐levelrichness.Results:Bodysizehadthestrongesteffectonspeciesrichnessacrossallthreespatialscales.Reefareaandtemperaturewerebothpositivelycorrelatedwithrichnessatall

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1  | INTRODUC TION

Determining theproximal andultimate causes of species richnessisfundamentaltounderstandwhysomeregionscanaccommodateanextraordinarydiversitywhereasothers contain just a few spe‐cies (Lessard, Belmaker, Myers, Chase, & Rahbek, 2012). Studieshavepostulatedthatthedynamicsofdispersal,speciationandex‐tinctionoverlargetemporalscalesshaperegionalpoolsofspecies,whereas,locally,speciescompositionispresumablyinfluencedmorestronglybylocalecologicalprocesses(e.g.,mutualism,competitionorpredation;Ricklefs,2004;Srivastava,1999).However,disentan‐glinghowregionalversuslocalprocessescontributetocommunitycompositionandspeciesrichnessremainschallenging(e.g.,Cornell&Harrison,2014),andyetitiscrucialtounderstandwhydifferentregionsexhibitsuchdramaticdifferencesinbiodiversity.Intropicalcoral reef systems, for instance, species numbers increase rapidlyfromsmalltransectstowholeislands,culminatinginabewilderingregionalrichness;whereasinmoretemperaterockyreefsnewspe‐ciesaccumulateatamuchslowerpaceasspatialscaleincreases,re‐sultinginasubstantiallylowerregionalrichness(Edgaretal.,2017;Witman,Etter,&Smith,2004).Wepostulate that thispattern re‐flectsintrinsic(e.g.,bodysizeandlife‐historystrategies)andextrin‐sicfactors(e.g.,temperatureandgeographicbarriers),andthattheirinteractionultimatelyexplainsthecontrastinglevelsofspeciesrich‐nessandspatialstructureacrossprovinces.

Thedynamicsofpopulationslocallyandalongthemeta‐commu‐nitycontinuumdictatehowspeciesaccumulateacrossspatialscales.Populationdynamicsacrossspaceandtimearefundamentallydeter‐minedbyresourcedemandsandlifehistory(Peters,1983),dispersalcapacity(Luizetal.,2013),andlocalabundance(Reuman,Gislason,Barnes,Mélin,&Jennings,2014),allofwhicharestrongcorrelatesof body size. In reef fishes, smaller species are more abundant(Ackerman,Bellwood,&Brown,2004;Barneche,Kulbicki,Floeter,Friedlander,&Allen,2016),havesmallerhomeranges(Nash,Welsh,Graham,&Bellwood,2014),andhavemorelimitedgeographicrangewhencomparedtolargerspecies(Stier,Hein,Parravicini,&Kulbicki,2014).Theorypredicts,andevidencesuggeststhatsize‐correlatedtraits, particularly abundance, home range, dispersal capacity andgeographic range, should interact todefinehowtheaccumulationofspeciesplaysoutacrossspatialscales,fromsmalltransectstoen‐tirebiogeographicprovinces(Allen&White,2003;Belmaker,2009;Brown&Nicoletto, 1991;Reumanet al., 2014).However,we stilllackexplicittestsofwhetherbodysizecontributestotheaccumu‐lationofreef‐fishspeciesrichnessacrossspatialscalesaroundtheglobe(butseeBelmaker,2009forexistingcross‐scalecomparisons).

Inadditiontobodysize,environmentalandgeographicfactorsareoften invoked to explain gradients in species richness. For in‐stance, the theory of island biogeography (MacArthur &Wilson,1967)statesthatspeciesrichness increaseswithhabitatarea,anddecreaseswithdegreeofisolation.Inevolutionarytime,thedegree

spatialscales.Atthesitescaleonly,richnessdecreasedwithreefisolation.Speciesrichnesswasnotcorrelatedwithproxiesofhumanimpacts.Speciespackingwascor‐relatedwithspeciesrichnessattheprovincelevelfollowingasub‐linearpowerfunc‐tion.Province‐leveldifferencesinspeciesrichnesswerealsomirroredbypatternsofbodysizedistributionatthesitescale.Species‐richprovincesexhibitedheterogene‐ous assemblages of small‐bodied specieswith small range sizes,whereas species‐poorprovincesencompassedhomogeneousassemblagescomposedbylargerspecieswithgreaterdispersalcapacity.Main conclusions:Ourfindingssuggestthatbodysizedistribution,reefareaandtem‐perature aremajor predictors of species richness and accumulation across scales,consistentwithrecenttheorieslinkinghomerangetospecies–arearelationshipsaswellasmetaboliceffectsonspeciationrates.Basedonourresults,wehypothesizethat in less diverse areas, species are larger and likelymore dispersive, leading tolargerrangesizesandlessturnoverbetweensites.Ourresultsindicatethatchangesinprovince‐level (i.e.,regional)richnessshouldleaveatractablefingerprint in localassemblages,andthatdetailedstudiesonlocal‐scaleassemblagecompositionmaybeinformativeofresponsesoccurringatlargerscales.

K E Y W O R D S

biogeography,communityassembly,localdiversity,neutraltheory,regionaldiversity,spatialscale,speciesenergy

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ofisolationamongconnectedsites(Hubbell,2001)willdirectlyaffecthownewspeciesaccumulate inspace (i.e., fromsites toentireprov‐inces), as species’ ability todisperse isexpected toaffectgene flow,vicariance,andultimatelyspeciationrates.Studieshaveshownthat,inectotherms,bodysizeandenvironmentaltemperaturecandirectlyaf‐fectbothdispersalcapacity(Luizetal.,2013;O’Connoretal.,2007)andspeciationrates,viaeffectsonindividualmetabolicrates(Allen,Gillooly,Savage,&Brown,2006).Infact,modelsthatcombinethermaleffectsonspeciationrates(Allenetal.,2006)withmeta‐communitydynamicscanreproducerealisticlatitudinaldiversitygradientscurrentlyobservedintheworld’soceans(Tittensor&Worm,2016;Worm&Tittensor,2018).

Externally to “natural” factors, anthropogenic impacts can in‐fluence community composition due to over‐harvesting, habitatdegradationand introductionofnon‐nativespecies,contributingtomultipleprocessessuchastrophiccascadesandbiotichomogeniza‐tion(Dornelasetal.,2014;Jacksonetal.,2001).Forreefecosystemsinparticular,recentstudiesshowthatpopulationsizeofhumansettle‐mentsandaccessibilitytofishmarketscanhaveanegativeeffectonfishbiomass(Cinneretal.,2016).Yet,itisstillunknownwhethersuchanthropogenicimpactsexhibitconsistenteffectsonspeciesrichnessacrossspatialscales,whichisimportantbecause,atpresent,extinc‐tionshavebeenobservedatsmallscalesbutrarelywithinandacrosslargebiogeographicprovinces(Kulbicki,Parravicini,&Mouillot,2015).

Tounderstandhowthesefactorsmightaffectspeciesrichnessatdifferent scales,herewepresentaglobal analysisofhow reef‐fishspeciesrichnessbuildsupinspace,fromlocalsitestobiogeo‐graphicprovinces.Wetestwhetherbodysize,reefarea(proxyforhabitat availability) and isolation,humandisturbance, and sea sur‐facetemperature(SST)correlatewithspeciesrichnessacrossspatialscales.Reeffishesprovideanidealmodelforinvestigatingthisprob‐lembecausetheyarespecies‐rich(Parravicinietal.,2013),globallywidespread,andeasytosamplewithahighlevelofaccuracy.Reeffishesalsorepresentamajorfoodsourceformillionsofpeople(Teh,Teh,&Sumaila,2013)andvaryconsiderablyinbodysize(Kulbickietal.,2015).Weshowthat,aftercontrollingforthesampling‐relatedgroup effects, and consistent with recent theoretical predictions(Allen&White,2003;Reumanetal.,2014;Tittensor&Worm,2016;Worm&Tittensor,2018),bodysize,reefareaandtemperaturearesystematically correlated with species richness and accumulationacrossspatialscales.Inlightofourfindings,wehypothesizethatinlessdiverseareas,speciesarelargerandlikelymoredispersive,lead‐ingtolargerrangesizesandlessturnoverbetweensites.

2  | METHODS

2.1 | Database and field sampling

Wecompiledaglobaldatabasethatencapsulatesseveraldecadesoffielddatacollectionbyseveraloftheauthors(Barnecheetal.,2018). Itencompasses13,050belt transectsacross485sites (islands,at‐ollsandcoastalcontiguousreefs)spreadthrough14tropicalbiogeo‐graphicprovinces[TropicalEasternPacific,OffshoreTropicalEasternPacific, Easter Island, TheHawaiian archipelago, Polynesia, Central

Pacific,SWPacific,CentralIndo‐WestPacific,WesternIndianOcean,NWIndianOcean(RedSea),EasternAtlantic,OffshoreSWAtlantic,SWAtlanticandtheCaribbean;Figure1,SupportingInformationTableS1].Sitesspana28‐folddifferenceinspeciesrichness(Figure1e).

Reef‐fish assemblages were surveyed through belt transectsof different areas depending on the data source (SupportingInformation Table S1).Data fromCuba, Bahamas andBelizewerecollectedaspresence/absencedata.DatafromsomesitesalongthePacificcoastofMexico(areaof40m2)andtheCaribbean(areaof100 m2)werecollectedastotalabundancecounts.Atallremainingsites,diverstalliedthenumbersandbodylengthsofallfishsimulta‐neously.Alltransectsstartedandendedapproximatelyatthesamedepth(within3mofdepthvariation)andwereorientedparalleltothereef.Weonlyutilizedtransectsconductedoverhard‐reefbot‐toms in order to make a representative comparison across prov‐inces and reduce methodological bias generated by multi‐habitatcomparisons(Srivastava,1999).Siteswithfewerthanthreesampleswereexcludedfromthedatabase.Atotalof2,523specieswasob‐servedacrossall transects.Toquantifyoverall species richness intheseprovincesandestimatethepotentialeffectsofsamplingbiasassociatedwithfieldtransects,wecontrastedthesedataagainstanexhaustivechecklist,thatis,acompilationofpublishedlistsofspe‐ciesoccurrencesatmultiplesites.Eachsite‐specificlistwasassem‐bledbycombiningmultiplemethodsofsamplinginordertoobtainathoroughassessmentofspeciesrichness,includingthatofsmall‐bodiedspecies.Thischecklistencompassesatotalof5,410species(Parravicinietal.,2013;SupportingInformationTableS2).Belowweexplain howwe standardized the different transects for the pur‐posesofestimatingspeciesrichnessatmultiplescales.

Wealsocompiledinformationonbodysizedistribution,reefareaand isolation,humandisturbance(gravityofhumansettlementandgravityofhumanmarket,basedonpopulationsizeandtraveltime)and SST for each site, sub‐province and biogeographic province.Succinctly, species‐level maximum adult body size was obtainedfrom the published literature andonline databases, and themodal(i.e.,themostfrequent)sizewascalculatedforeachspatialscale[forvisualization purposes, we sometimes divide these estimates intooneofsixclassesfollowingParravicinietal.(2013):0–7cm,7–15cm,15–30cm, 30–50cm, 50–80cm and >80cm]. Reef area [obtainedfromtheCoralReefMillenniumCensusProjectandHalpern&Floeter(2008);see“Modelpredictors”sectionintheSupportingInformationAppendixS1]wasestimatedina12‐kmradiusaroundeachsite,andsummedacrosssiteswithinsub‐provincesandsub‐provinceswithinprovinces to obtain estimates at higher scales,while reef isolationwas calculated as the distance to the coast or the distance to thenearestreef.Humandisturbancewasestimated,followingMaireetal.(2016)andCinneretal.(2016),astheratiobetweenthepopulationofthenearestmajormarketorthenearesthumansettlementdividedbythesquaredtraveltimetoreacheachsite(i.e.,gravity),averagedfor analyses across localities and then provinces. And finally, SSTwasobtainedfromdailytime‐seriesdatafromtheNationalOceanicandAtmosphericAdministrationof theUSA (NOAA)coveringa5‐year period (°C; 0.25° resolution) (Reynolds et al., 2007; available

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F I G U R E 1  Reef‐fishspeciesrichnessacrossscales.Forclarity,theworldmapin(a)wasdividedintomajorgeographicrealms(dashedlines)thataccommodatemultiplesites(points)withinbiogeographicprovinces(differentcoloursandsymbols).In(b–e),weshowthespeciesrichnessatthechecklist(i.e.,listofspeciesoccurrences;n=132sites,SupportingInformationTableS2),province,sub‐provinceandsitescales,respectively,withpointsbeingorderedonthexaxisbasedontheirlongitudesin(a).In(c–e),speciesrichnesswasestimatedusingcoverage‐basedrarefaction,andthemeancoverageamongpoints(±SD)isgivenatthetoprightcorner[Colourfigurecanbeviewedatwileyonlinelibrary.com]

(a)

(b) (c)

(d) (e)

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from https://www.esrl.noaa.gov/psd/data/gridded/data.noaa.oisst.v2.highres.html).Wedescribeindetailhowthesevariableswerees‐timated, thediagnosticanalysesperformed toensure thatour sta‐tisticalmodelsareunbiased,andtheresultsrobusttodifferentsetsofassumptions,inSupportingInformation(AppendixS1:TableA1).

2.2 | Species richness at different scales

Forthepurposesofourstudy,weadoptedthreenestedspatialscales:sites, sub‐provinces and biogeographic provinces (see SupportingInformationTableS1forgeographiccoordinates).Sitesaredefinedassmallislandsorstretchesofcontinuousreefsinlargerislandsorcoast‐lines(e.g.,ArvoredoIslandinsouthernBrazil,orreefsaroundNoumeainNewCaledonia,i.e.,c. 10sofkm).FollowingEdgaretal.(2017),weaggregatedsitesiftheywerecloserthan12kminlineardistancefromoneanother.Sub‐provincesencompasssitesthatbelongtothesamebiogeographicsub‐provinces (e.g.,CapeVerde,Fiji,Meso‐AmericanBarrierinMexico,i.e.,c. 100sofkm).Finally,biogeographicprovincesarewell‐definedregions (i.e.,>1,000sofkm) that followtherecentclassificationproposedbyKulbickietal. (2013)basedonhierarchi‐cal analyses of reef‐fish species composition.However,we furtherseparatedtheSWAtlantic intocontinental (i.e.,Braziliancoast)andoffshore(oceanicislands)followingFloeteretal.(2008).

We estimated species richness at the site, sub‐province andprovince scales using coverage‐based rarefaction (i.e., samplingcompleteness).Samplingcoveragerepresentstheproportionofthetotalnumberofindividualsinacommunitythatbelongtothespeciesrepresentedinthesample(Chao&Jost,2012).Incontrasttoclassicsample‐basedor individual‐basedrarefactionmethods, thiscover‐age‐basedsamplingtechniqueprovidesmorereliableestimatesofspeciesrichnessacrosscommunities.Thisisbecausewhileafixedareaornumberofindividualsmaysufficetorepresentlow‐richnesscommunities, itmaybeinsufficienttorepresentspecies‐richcom‐munities(seedetailsinChao&Jost,2012).CalculationsweredoneusingtheRpackageiNEXTversion2.0.12(Hsieh,Ma,&Chao,2016).Species richness (i.e.,HillnumberqD=0)wasestimatedby trans‐forming all transect information into presence/absencedata. Thisprocedure,concomitantlywiththehierarchicalmodelsaccountingfordifferencesinsamplingmethoddescribedbelow(seeStatistical analyses), ensured that all species richness estimates are directlycomparable.Estimatesatthesite,sub‐provinceandprovincescalesinthesemodelswerebasedonsamplingcoveragesof0.83,0.89and0.98,respectively,thatcorrespondtothehighestcoveragevaluesyielding robust, unbiased estimations across all spatial scales ac‐cordingtothepackage’salgorithm(Chao&Jost,2012;Hsiehetal.,2016).Inotherwords,withthisapproach,weminimizemuchofthepotentialvariationinspeciesrichnessestimatesduetodifferencesinrelativeabundanceorcoveragesampling.

2.3 | Statistical analyses

At the site and sub‐province scales,we testwhethermodal bodysize,B;reefarea,A;distancetocoast,C;distancetonearestreef,R; gravityofhumanmarkets,M;gravityofhumansettlement,H; and

temperature,T,explainreef‐fishspeciesrichness,S,usingahierar‐chicallinearmodel,

where�0 is theestimatedmodel intercept,�[B,A,C,R,M,H,T] are fixed‐effect slopes,Δg represents random deviations from the modelintercept (on log scale) attributable to a grouping random vari‐ablethatrepresentsahigherspatialscale—thatis,sub‐provincesnestedinprovincesforthesitescale,andprovincesforthesub‐provincescale—and�representstheresidualvariation.Notethatby including Δgweareabletocontrolforotherunmeasuredvari‐ables thatmightotherwise lead tocorrelated residualsathigherspatial levels (e.g., forspatialautocorrelationorsamplingeffectsgiventhatsub‐provincesweregenerallystudiedbythesamere‐search group). Accordingly, the model residuals obtained at thesitescale,controllingfortheeffectsofsub‐provincenestedwithinprovinces,werenotspatiallyautocorrelatedaccordingtoMoran’sItest(p=0.09).Therefore,ourhierarchicalmodeladequatelycon‐trols for the spatial structureof our sites.Wenote that speciesrichnessisfunctionallydependentonsamplingarea,andthatper‐hapsourresultscouldbebiasedbynotincludingthiscovariateinthemodel.Ourmainfindingswithregardstotheeffectsofbodysize,reefareaandtemperaturearemaintainedevenafterinclud‐ing total sampling area as a covariate (Supporting InformationAppendixS1:TableA4).

Attheprovincescale,duetothesmallnumberof independentsamples(n=14),wefitseparatelinearregressionsoftheform

Ineachregression,werespectivelyusedmodalbodysize, reefarea, and temperature as predictors because they were the onlyvariableswith consistently strongeffect sizes (i.e., slopes)bothatthesiteandsub‐provincescales(seeResultssectionbelow).Giventhatweonlyhave14observationsatthisscale,addingmultipleco‐variatesatoncewouldoverfitthemodel.

WefitEquations1and2 inaBayesian frameworkbyusing theRpackagebrmstoderiveposteriordistributionsandassociated95%credibleintervals(CIs)forthefittedparameters.Bothfixed(�[B,A,C,R,M,H,T]) andrandom(Δg)effectswereassignednormallydistributedpriorsthatwerevague(i.e.,locallyuniformovertheregionsupportedbythelike‐lihood),withmeansofzero.Modelresiduals(�),andstandarddevia‐tionsforboththerandomeffects(�

[

Δg

]

)andmodelresiduals(� [�]), werealsoassignedweaklyinformativepriorsfollowingaStudent’st distribution. The posterior distributions of model parameters wereestimatedusingMarkovchainMonteCarlo(MCMC)methodsbycon‐structingthreechainsof2,000steps,including1,000‐stepwarm‐upperiods,soatotalof3,000stepswereretainedtoestimateposteriordistributions (i.e., 3× (2,000−1,000) = 3,000). Fixed effectswereconsidered statistically significant if theirposterior95%CIsdidnotoverlapzero.WeuseBayesianR2inordertoestimatetheamountofexplainedvariationofeachmodel (Gelman,Goodman,Gabry,&Ali,2017).PosteriorpredictivechecksforallthreemodelsareprovidedinSupportingInformationAppendixS1:FigureA1.

lnS= (�0+Δg)+�BlnB+�AlnA+�ClnC+�RlnR+�MlnM+�HlnH+�TT+�

lnS=�0+�BlnB+�.

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Wealsotestedwhetherreef‐fishspeciesrichnessatthetransectscale(i.e.,speciespacking=species/m2)wascorrelatedwithrichnessattheprovincelevel.Todoso,weusedatwo‐stepapproach.First,

we ran a Bayesian hierarchical linear model with richness at thetransectscaleasafunctionoftransectareaonalog‐logscale.Wedo so given the nonlinear nature of the species–area relationship

F I G U R E 2  FitteddatabasedonourBayesianhierarchicallinearmodelshowingtheeffectsofmodalbodysize(a–c),reefarea(d–f),andtemperature(g–i)onreef‐fishspeciesrichness(fromFigure1c–e)atthesite(leftcolumn,Equation1),sub‐province(middlecolumn,Equation1)andprovince(rightcolumn,Equation2)scales.Panelsatthesite(a,d,g)andsub‐province(b,e,h)scalesdepictthepartialeffectsofeachvariableaftercorrectingspeciesrichnessfortheeffectsofallremainingfixed‐effectcovariates.Attheprovincescale,threeseparatemodelshavebeenfitted,eachforadifferentpredictor.Atthesiteandsub‐provincescales,speciesrichnesshasbeencorrectedfortherandomeffects(respectivelysub‐provincenestedinprovince,andprovince).Bottomleftvaluesrepresentmean(±SD)coverageamongdatapoints(Cov.),whicharethesameforplotswithinthesamecolumn.BayesianR2aredisplayedwithassociated95%credibleintervals(CIs).Panels(d)and(g)aregeneratedfromthesamemodelaspanel(a),andthereforecontainthesameBayesianR2[similarlyforpanels(b),(e)and(h)].Panels(c),(f)and(i)aregeneratedfromthreeseparatemodelsasexplainedinthetext,andthereforehavedifferentBayesianR2values.Thindashedlinesshow95%BayesianCIsaroundthemeanmodelprediction.ColoursandsymbolsasinFigure1.SST=seasurfacetemperature.[Colourfigurecanbeviewedatwileyonlinelibrary.com]

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)

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(Rosenzweig, 1995). Sites nested in sub‐provincesnested in prov‐inces were used as a random effect. Model fitting specifications(numberofMCMCsamples,chains,warm‐upperiods,andpriordis‐tributions)followthesamespecificationsofthemodelinEquation1.Becausetherandom‐effectcoefficients representdeviations fromtheestimatedmodelintercept,ateachoneofthespatialscaleswesummedeachrandom‐effectcoefficientwiththemodelinterceptinordertoobtainameasureofspeciespacking(species/m2).Second,weranordinaryleastsquaresforeachofthe3,000posteriorsam‐plesfromourrandom‐effectcoefficientsattheprovincescale(i.e.,species packing on the log scale) against province‐level speciesrichness(alsoonthelogscale)—asestimatedusingcoverage‐based

rarefaction(coverage=0.98).Thisapproachallowedustoestimateameanslopebetweenspeciespackingandprovince‐levelrichness,and R2valueswithassociated95%CIs.Aslopeof1wouldindicatethatspeciespackingisdirectlyproportionaltoprovince‐levelrich‐ness (i.e., a linear relationship),whereas a slope >0 and <1wouldindicatethatspeciespackingscalessub‐linearlywithprovince‐levelrichness.

All analyses were repeated removing the smallest size class(<7cm)tocircumventpotentialproblemsofunder‐detectionduringsampling(SupportingInformationAppendixS1:TableA2).WealsofitthemodelatthesitescaleseparatelyfortheAtlanticandAmericasasagroup(i.e., includingtheTropicalEasternPacific),andtherest

F I G U R E 3  Violinplotsshowingthedifferenceinspeciesrichnessamongprovincesforeachofthesixbodysizeclassesconsideredinourstudy,whicharerespectivelyindicatedatthetoprightcornerinitalics.Eachviolinrepresentsadistributionofsiteswithinagivenprovince(bottompointsasinFigure1).Wefilteredourdataforeachclass,andestimatedthespeciesrichnessusingcoverage‐basedrarefaction,andthemeancoverageamongpoints(±SD)isgiveninthetoprightcornerofeachplot.Blackdashedlinesseparatemajorgeographicrealms[Colourfigurecanbeviewedatwileyonlinelibrary.com]

(a) (b)

(c) (d)

(e) (f)

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of thePacific as anothergroup (Supporting InformationAppendixS1:TableA6).

3  | RESULTS

3.1 | Site scale

Ourmodelexplained73.6%ofthevariationinreef‐fishspeciesrich‐ness across sites (Equation 1),which ranged from10 to 288 spe‐cies. After controlling for all covariates, reef‐fish species richnessdecreasedwithmodalmaximumbodysize(Figure2a).Afterbinningspecies richness based onmaximum body sizes, we observe thatsmall‐bodiedspeciesprevailinspecies‐richsites,particularlyinthePacific region (Figure3b,c).Weobservedthat therateof increaseinbiodiversitywith sampledarea (i.e., thenumberof transects) issubstantiallyhigherinspecies‐richprovinces(Figure4a).However,speciespackingincreasedsub‐linearlywithprovince‐levelrichness(slope=0.26,95%CI=0.15–0.36;R2=0.55,95%CI=0.28–0.78;

SupportingInformationAppendixS1:FigureA2).Moreover,theob‐servedmodalbodysizeisconsistentlysmaller(i.e.,lowmeanvalueandlowervariances,Figure4b,c)withintherichestprovinces.Inpar‐ticular,theestimatedslopeforthemodeofthebodysizedistribu‐tionwas thestrongestamongallestimatedslopes (�B:−0.70;95%CI:−0.87to−0.51),implyinga74.0%decreaseinrichnessovertheobservedrangeofmodalbodysizes(from67to9.65cm).

Speciesrichnessincreasedwithreefarea(�A:0.05;95%CI:0.02–0.08; Figure 2d), and decreasedwith distance to the closest reef(�R:−0.02;95%CI:−0.03to−0.00).Ourmodelalso indicatedthatspecies richness increases with SST (�T: 0.05; 95% CI: 0.01–0.09;Figure 2g), implying a 52.4% increase in richness going from21.3to29.73°C.

Variablesrelatedtohumandisturbance(gravityofmarketsandgravity of nearest human settlement) and distance to coast werenot significantly correlatedwith species richness (respectively�M: 0.00;95%CI:−0.02–0.02;�H: 0.00;95%CI:−0.01–0.01;�C: 0.02; 95%CI:−0.00–0.04).Thehierarchicalstructureofourmodel,with

F I G U R E 4  Richnessandbodysizeacrossdifferentspatialscales.In(a),sample‐basedrarefactioncurves(basedon500permutations)ofreef‐fishspeciesrichnessshowhowreef‐fishspeciesrichnessaccumulatesassamplingeffortincreasesindifferentprovinces.Meanrichnessisshown(±95%confidenceintervals).Meanmodalbodysize(b)andvarianceinsize(c)ofthespeciespoolacrossdifferentsamplingareas,andacrosssiteswithinourchecklist(fromFigure1b;SupportingInformationTableS2).Bodysizemeansandvariancesateachprovincewereestimatedfromrandomlypermutedsubsetsoftransectsbasedon1,000permutations(1,5,10or15transects),oracrossalltransects(All),oracrossallsitesforthechecklistdata(Checklist).ColoursandsymbolsasinFigure1[Colourfigurecanbeviewedatwileyonlinelibrary.com]

(a)

(b)(c)

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sub‐provincesnestedinprovincesasourrandom‐effectgroup,wasabletocaptureconsiderablevariationinspeciesrichnessatdiffer‐entscales.Particularly,afteraccountingforthefixedeffects,weob‐serveda1.55‐foldvariationamongsub‐provincesonaverage (i.e.,≈e0.22×2with�

Δg=0.22).

Thedirectionandsignificanceoffixed‐effectcoefficientswereallsimilarafterremovingthesmallestsizeclass(<7cm;SupportingInformation Appendix S1: Table A2). Results for the Atlantic +Americas,andtherestofthePacific,showthatthemeanmodelcoefficients and their directions (i.e., positive or negative) aremaintainedwithin the Pacific, but are not significantwithin theAtlantic +Americas (Supporting InformationAppendix S1: TableA6).

3.2 | Sub‐province scale

At the sub‐province scale, reef‐fish species richness ranged from15to364species.Ourmodel(Equation1)explained78.8%ofthevariationinspeciesrichness.Consistentwiththemodelatthesitescale,aftercontrollingforallcovariates,reef‐fishspeciesrichnessdecreasedwithmodalmaximumbodysize(Figure2b).Speciesturn‐overmovingfromsitestosub‐provinceswasmostpronouncedforsmall‐bodiedspecies(SupportingInformationAppendixS1:FigureA3).Themodal‐sizeestimatedslopewasagainthestrongestamongallestimatedslopes(�B:−0.77;95%CI:−1.11to−0.43).Apartfrommodalmaximumbodysize, reefarea (Figure2e)and temperature(Figure2h)weretheonlyothersignificantvariablesinourmodel(�A:0.08;95%CI:0.04–0.12;�T:0.05;95%CI:0.00–0.11).Ourmodelindicates thatafteraccounting for the fixedeffects, species rich‐ness varies by2.41‐fold amongprovinces (i.e.,≈e0.44×2with�

Δg =

0.44).After the removal of the smallest size class,modal body size,

reefareaandtemperaturewerestillsignificantandinthesamedi‐rectionas themainmodel. (Supporting InformationAppendixS1:TableA2).

3.3 | Province scale

Consistentwithourfindingsatthesiteandsub‐provincescales,bodysize(Equation2)explained61.2%ofthevariationinspeciesrichness(rangingfrom44to806species)attheprovincescale.Particularly,province‐levelrichnessdecreasedwith increasingmodalmaximumbodysize (�B:−2.79;95%CI:−4.14to−1.43;Figure2c).Similaref‐fectsweredetectedafterremovingthesmallestsizeclass(�B:−2.68;95%CI:−4.04to−1.35;SupportingInformationAppendixS1:TableA2).Wealsoanalysedtherelationshipbetweenspeciesrichnessandarea(Figure2f)ortemperature(Figure2i)intwoseparatelinearre‐gressions(SupportingInformationAppendixS1:TableA5),andbothvariableswerepositivelycorrelatedwithspeciesrichness.Reefareawaspositivelycorrelatedwithrichness(�A:0.22;95%CI:0.08–0.37;Figure2f),andexplained46.5%ofthevariationinspeciesrichness.Temperaturewasalsopositivelycorrelatedwithrichness (�T: 0.31; 95%CI:0.00–0.62;Figure2f),andexplained30.7%.

4  | DISCUSSION

Our results indicate that reef‐fishmodal body size, reef area, andenvironmental temperature are consistently correlated with reef‐fish species richness across spatial scales (Figure 2, SupportingInformation Appendix S1: Table A5). The fact that body size wasnegativelycorrelatedwithspeciesrichnessatallspatialscalesmaysuggestthattheobservedaccumulationofspeciesacrossspace isstronglyassociatedwithsmallerbodysizes(Figure3).Thisinterpre‐tationisconsistentwithpreviousstudiesshowingthatbetadiversityacrossscalesisdrivenbytheaccumulationofsmallerspeciesinmam‐mals(e.g.,Brown&Nicoletto,1991)andreeffishes(e.g.,Belmaker,2009).Moreover,ourempiricalresultslendsupporttothe“marinediversityspectrum”theoryproposedforpelagicmarineecosystems(Reumanetal.,2014),wherebythenegativelinearrelationshipbe‐tweenrichnessandbodysizearisesduetothesizedependenceofhomerangeanddispersalcapacity(Allen&White,2003;Reumanetal.,2014)thathasbeenpreviouslyobservedinreeffishes(Luizetal.,2013;Nashetal.,2014).

Wenote that sites thatare rich in smaller‐bodied reef fishesalsoencompassarangeofsuitable,heterogeneoushabitats(e.g.,hardandsoftcorals,sponges,algae;Messmeretal.,2011),andourresults indicatethat increasinghabitatareawillalsoyieldhigherspecies richnessacrossscales.Wenote thatouranalysiscannotresolvethecausalityoftheserelationshipsgiventhatshallow‐reeforganisms (e.g., reef‐building corals and reef fishes) show a par‐allel history of diversification through time (Bellwood, Goatley,&Bellwood,2017).However, the fact thatbodysizevarieswithrichnessevenwithinagradientofspecies‐richsitesandprovinces(e.g.,fromIndo‐WestPacifictoPolynesia)suggeststhattheevolu‐tionaryprocessesassociatedwiththediversificationofreeffisheshave aided speciation within smaller‐bodied species. In particu‐lar, thecentreoforiginandaccumulationhypothesis states thatthericherIndo‐WestPacificisaproductofaseriesofeventsthatfacilitated both the speciation (“cradle”) as well as the accumu‐lation (“museum”) of existing species through time (Bellwood etal., 2017).Our findings couldbe consistentwith this hypothesisconsideringthatIndo‐WestPacificreefshavegonethroughase‐riesofsea‐levelchangesleadingtotemporallyvariablegeographicisolation (Bellwoodetal.,2017).Therefore, speciationmayhavebeen further promotedby vicariancebecause small‐bodied spe‐cies have, on average, lower realised dispersal capacity (Luiz etal.,2013).

Afteraccountingfortheeffectofsamplingarea,speciesrichnessatthetransectscalescaledsub‐linearlywithprovince‐levelrichness(Supporting Information Appendix S1: Figure A2). The sub‐linearnature of this relationship corroborates the suggestion of recentstudiesthatspeciesrichnessestimatedatsmallspatialscalesmightnotnecessarilyresemblethatattheprovincescale(Dornelasetal.,2014;Vellendetal.,2013).Wespeculatethatthisobservedphenom‐enon reflects the interaction between body size, local abundanceandgeographicrange(SupportingInformationAppendixS1:FigureA4a),assmallerspeciesaregenerallymoreabundant(Ackermanet

324  |     BARNECHE Et Al.

al.,2004;Barnecheetal.,2016)andoftenexhibitsmallergeographicrangesizes than larger species (Belmaker,2009;Luizetal.,2013).Consequently, it is expected that species at the extremes of thebodysizedistributionaredetectedinonlyasmallfractionoftran‐sects:forsmallspeciesthismayrelatetosmallerhomerangesizesand difficulties in visual detection, whereas for large species lowabundanceshouldresultinasmallrepresentationacrossthosetran‐sectswithin their geographic range (Preston’s veil; Preston, 1948).Ourdatastronglysupportthisinterpretation,withboththesmallestand largest sizeclassesbeing less frequently sampled innearlyallprovinces,exceptinEasterIsland(SupportingInformationAppendixS1:FigureA4b).Accordingly,whilepopulationabundancewasneg‐ativelycorrelatedwithbodysizeacrosssitesinasubsetofthedatausedhere(Barnecheetal.,2016),thenumberofprovincesinwhicheachspecieswasdetectedwaspositivelycorrelatedwiththeirmax‐imumsize (Supporting InformationAppendixS1:FigureA4c), indi‐catingthatsmallerspeciestendtohavesmallergeographicranges(SupportingInformationFigureAppendixS1:A4d).

Becauseoftheinteractionsbetweensize,abundanceanddistri‐bution,speciesofintermediatebodysizeconstitutethecoreofmostlocal assemblages in all provinces (Supporting Information FigureAppendixS1:A4b).However,bodysizedistributionsalsodiffersig‐nificantlyamongprovincesconcomitantlywithspeciesrichness.Thelinearregressionbetweentotalspeciesrichnessagainstmodalbodysizeattheprovincescale(Equation2,Figures2cand5a)givesrisetoacontinuum,withspecies‐poorperipheralprovincesoftheAtlanticfallingatoneextremeandhighlycomplexreefssuchasthoseintheIndo‐WestPacific,Polynesiaand,toalesserdegree,theCaribbeanattheother(Figure5a).Thus,thebodysizedistributionwithinlocalassemblages is indicative of the overall reef‐fish richness of their

respectiveprovinces.Thiscanbereadilyunderstoodbecauseme‐diumtolargefishesareexpectedtocontributetospeciesrichnessatthetransectlevel,withoutaproportionalcontributiontospeciesrichnessathigherspatialscales,iftheyarewidelyspread(seealsoReuman et al., 2014; Soininen, Lennon,&Hillebrand, 2007). As aconsequence, in provinces where larger fishes predominate, localassemblages should be more homogeneous in their compositionand exhibit body size distributions shifting towards higher values(Figure 5b). The opposite is expected in provinces occupied pre‐dominantlyby small species,which includeamultitudeof specieswithsmallgeographicranges.Again,thisimpliesthattheenormousdiversityofspecies‐richprovincesemergesprimarilyfromtheaccu‐mulationofsmallerspecieswithrestricteddistribution(Figure5b).

Ourmodelsatallscalesindicatethattemperaturewaspositivelycorrelatedwithspecies richness,consistentwith the idea that thelatitudinaldiversitygradientisinpartdrivenbythetemperaturede‐pendenceofectothermicmetabolismandspeciationrates(Allenetal.,2006;Tittensor&Worm,2016).Additionally,ourresultsaddtoavastnumberofstudiesthatsupportpredictionsfromthetheoryof islandbiogeography(MacArthur&Wilson,1967),wherebyspe‐ciesrichness increaseswith increasinghabitatarea,anddecreaseswithisolation.Forinstance,ithasbeenshownrecentlythatsmaller‐bodiedreef‐fishpreydeclinesmorerapidlywithincreasingisolationwhencomparedtolargerpredatorsacrossPacificreefs(Stieretal.,2014).Wenotethoughthatreefisolationwasnotsignificantatthesub‐provincescale.Thisdiscrepancybetweenscalescouldbeduetoourchoiceofmeasurementforisolation(meandistancetothenear‐est reef across sites).Given this caveat,our results are consistentwithrecenttheoreticalpredictions(Tittensor&Worm,2016;Worm&Tittensor,2018)thatsuggestthatthecombinedeffectsofarea,

F I G U R E 5  Thenegativerelationshipbetweenmodalbodysizeandspeciesrichnessacrossprovinces(a).In(b),weproposeconceptuallythatthepatternin(a)arisesfromthedifferentcontributionoflarge(top)versussmall(bottom)speciestotheobservedmeanbodysizeandlocal(butnotprovince‐level)richness.Distributions(blueforlargespecies,redforsmallspecies)representhypotheticalspecies‐specificlocalabundancesacrossspace.Localrichnesscanbesampledatanypointalongthiscontinuum,whereastheprovince‐levelrichnessarisesfromthesumofallspecies(i.e.,distributions).Forthepurposesofillustration,werepresentthelowandhighrichnessprovincesrespectivelywithlargeandsmallspeciesonly,butnoticethatinrealityprovincesaremadeupofamultitudeofspecieswithvaryingabundanceandgeographicranges.Coloursandsymbolsin(a)asinFigure1[Colourfigurecanbeviewedatwileyonlinelibrary.com]

(a) (b)

     |  325BARNECHE Et Al.

traitsinthespeciespool(e.g.,smallbodysize),andwarmertempera‐tureswill yieldhigherbetadiversityacross spatial scales,perhapsbypromotinghigherspeciationratesovertime,andhigherspeciesturnoveracrossspace(Allenetal.,2006;MacArthur&Wilson,1967;Tittensor&Worm,2016;Worm&Tittensor,2018).

Afteraccounting for theeffectsof reef‐fishbodysize, reefareaandisolation,temperature,samplingartefacts,andotherunmeasuredpotential biogeographic effects, human‐related disturbance metricsdid not show any significant effect on reef‐fish species richness atthesiteandsub‐provincescales.This finding isparticularly relevantbecauseitsuggeststhat,atleastlookingatthestudiedspatialscales,species richness, contrary toassemblagesizestructureandbiomass(e.g.,Cinneretal.,2016;Jacksonetal.,2001),isnotexplainedbythe“gravity”variables,whicharebasedonpopulationsizeandtraveltime.Thismay in largepartbearesultoftherelatively lowproportionofspeciesthatareexploited,withthericharrayofsmallfishesbeinglesslikely to be affected by humans through indirect mechanisms only(suchashabitatalteration).Itmayalsobeattributabletothefactthatourdatacollectionisrecentintime,anditispossiblethatthemajorityofsampledreefsarealreadyaffectedbyhumandisturbancetosomedegree.However,ourresultsmightsuggestthathabitatdegradationassociatedwithlossofcoralspeciesinspecies‐richprovincesmayhaveprofoundimpactsonspeciesrichness(Alvarez‐Filip,Dulvy,Gill,Côté,&Watkinson,2009)via its impactonsmaller species.On theotherhand,largerfishesmightbeabletodispersemoreeasilytowardsotherareas,mostlikelybecauseoftheirbettercapacitytosurviveandestab‐lishreproductivepopulations(Luizetal.,2013).ComparisonsbetweenPacificprovinces,theTropicalEasternPacificandtheCaribbeansup‐port this conjecture. The expansion of amosaic of reef habitats inthe Indo‐AustralianArchipelago during theOligocene/Miocenewasasignificantdriverofcladogenesis forcoral‐reef‐fishtaxa (Bellwoodetal.,2017),withsmaller‐sized lineageswith lowmobilityandsmallhomerangesradiatinginmultipleprovinces(Munday&Jones,1998).BeforetheclosureoftheIsthmusofPanama,theCaribbeanhadareef‐buildingcoralfaunathatmorecloselyresembledmodernIndo‐Pacificspecies. It further underwent a period of extensive faunal loss thathasresultedinthemodern‐dayAtlanticandEasternPacificfishfau‐nas(Bellwood&Wainwright,2002;Budd,2000;DiMartino,Jackson,Taylor,&Johnson,2018).Thepredominanceofintermediatetolargespeciesacrossbothsidesofthe IsthmusofPanama(Figure4b)mayhave resulted both from long‐term andmore recent loss of habitat(Alvarez‐Filipetal.,2009).Thisprovidescircumstantialevidencethatassemblagestructureisalteredbyhabitatlossinapredictablemanner(Wilson,Graham,Pratchett,Jones,&Polunin,2006).Althoughspecu‐lativeatpresent,thishypothesiscanreadilybetestedinfuturestudies.Infact,recentevidenceindicatesthatsmallspeciesmightsufferthemostpronouncedlagstotrackingglobalchanges(Grahametal.,2007).

Herewedemonstratethatinreeffishes,fishbodysize,reefarea,and temperature can empirically predict species richness acrossspatial scales remarkably well. Therefore, our study lends strongsupport to theories that predict geographic gradients in speciesrichness basedon the combinationof demographic processes thatdepend on habitat availability, size‐dependent traits such as home

range, dispersal andgeographic range, andphysiological processessuchasthetemperature‐dependenceofmetabolismandspeciationrates(Allen&White,2003;Allenetal.,2006;Reumanetal.,2014;Tittensor&Worm,2016).Wehypothesize that species richnessatsmallspatialscalesbuildsupintoprovince‐levelspeciesrichnessatratesthatareinverselyrelatedwiththegeographicrangesizeofitsconstituentspecies,everythingelsebeingequal;inotherwords,reefswithlarger,betterdispersingspeciesshouldexhibit lessbetadiver‐sitybecausethesespeciesarefoundinalllocalities.Intheabsenceofgoodproxiesofabundanceandrangesizeinothertaxonomicgroups,thesepatternsthatmightbequitegeneralacrosssystemsmayremainunnoticed. Finally, at short temporal scales, activities that impactbothsmall‐(e.g.,habitatdegradation)andlarge‐sized(e.g.,overfish‐ing)speciesmightaffectgradientsinspeciesrichnessinpredictableways.At longer temporal scales, the above effects combinedwithnoveltemperatureregimesduetoclimatechangeshouldsetthefateofenvironmentalgradientsinspeciesrichness.

ACKNOWLEDG MENTS

WethanktheFrenchFoundationforResearchonBiodiversity(FRB)and theCenter of Synthesis andAnalysis of Biodiversity (CESAB)forfundingtheGASPARworkinggroupfromwhichthisstudywasgenerated.We also thank A. P. Allen, L. C. Strotz, J. Belmaker, J.E. Williamson and M. Westoby for comments on earlier drafts.Thanksalso toD.Tittensor,F.A.Zapata, J.P.Quimbayoand J.P.Krajewskiwho shared their data, and all field assistants. ELRwassupportedbyaBolsaJovemTalento(CNPq402053/2012‐5),grantFB002fortheCenterforAppliedEcologyandSustainability,line3,andFondodeCienciasyTecnología,Chile (FONDECYT1170017).FinancialsupportfromBrazil:SISBIOTA‐Mar(PI:S.R.FloeterCNPq563276/2010‐0andFAPESC6308/2011‐8),Pro‐Africa(PI:C.E.L.FerreiraCNPq490531/2007‐5),CAPES,MarinhadoBrasil,InstitutoLaje Viva; France: Institut de Recherche pour le Développement(IRD),PRISTINEproject (FondationTotal);Mexico: L.E.Calderón‐Aguilera (CICESE), A. L. Cupul‐Magaña, C. M. Galván‐Villa(Universidad de Guadalajara), H. R. Reyes‐Bonilla, A. Ayala‐Bocos(UABCS),R.A.López‐Perez(UMAR),E.Nuñez(UNACAR),fieldworksupportedbyCONABIO(PI:L.E.Calderón‐AguileraprojectHJ026),PROMEP (PI: F. A. Rodríguez‐Zaragoza, projects 103.5/08/2919and103.5/10/927)andSEP‐CONACYTprogrammes(PI:J.E.Arias‐González); Honduras: A. Medina, P. Rico (WWF‐CA), M. Aronne(Fundación Cayo Cochinos), fieldwork supported by WWF‐CA,USAID,FFEMandUniversidaddeGuadalajara(PI:F.A.Rodríguez‐Zaragoza);Nicaragua: R. Barnutti (INPESCA), fieldwork supportedby WWF‐CA, USAID and Universidad de Guadalajara (PI: F. A.Rodríguez‐Zaragoza); USA: National Geographic Society (PI: S. R.Floeter;A.M.Friedlander).

AUTHOR CONTRIBUTIONS

DRB,SRFandELRconceivedthestudy.Allauthorshelpedtocollectandcompiledata.DRBandELRanalysedthedataandwrotethefirstdraft.Allauthorscontributedtosubstantialrevisions.

326  |     BARNECHE Et Al.

DATA ACCE SSIBILIT Y

All data and R code (data manipulation, analyses, figures and tables) can be downloaded from a GitHub repository (https:// github.com/dbarneche/geb12851).Whenusingthisdatabase,pleasecite itas:Barneche,D.R.,Rezende,E.L.,Parravicini,V.,Maire,E.,Edgar,G.J.,Stuart‐Smith,R.D.,Arias‐González,J.E.,Ferreira,C.E.L.,Friedlander,A.M.,Green,A.L.,Luiz,O.J.,Rodríguez‐Zaragoza,F. A., Vigliola, L., Kulbicki,M.,& Floeter, S. R. (2018). dbarneche/geb12851:Publishedversionofpaperdataandcode:Bodysize,reefarea,andtemperaturepredictglobalreef‐fishspeciesrichnessacrossspatial scales (Version v1.0.0). Zenodo. https://doi.org/10.5281/zenodo.1484591

ORCID

D. R. Barneche https://orcid.org/0000‐0002‐4568‐2362

S. R. Floeter https://orcid.org/0000‐0002‐3201‐6504

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BIOSKETCHDiego Barneche studies theoretical and empirical approachesthat aim to unify evolutionary ecology across levels ofbiologicalorganization.Heispassionateaboutdata,code,andreproduciblescience.

SUPPORTING INFORMATIONAdditional supporting information may be found online in theSupportingInformationsectionattheendofthearticle.

How to cite this article:BarnecheDR,RezendeEL,ParraviciniV,etal.Bodysize,reefareaandtemperaturepredictglobalreef‐fishspeciesrichnessacrossspatialscales.Global Ecol Biogeogr. 2019;28:315–327. https://doi.org/10.1111/geb.12851