The Auk 116(1):116-130, 1999 PHYLOGENY OF THE FALCONIDAE INFERRED FROM MOLECULAR AND MORPHOLOGICAL DATA CAROLE S. GRIFFITFIS • Departmentof Ornithology,American Museum of NaturalHistory, Central Park West at 79thStreet, New York, New York 10024, USA ABSTR^CT.--Moleculardata and variationin syringealmorphology were used to infer a phylogenyfor the family Falconidaeand to addressthree issuescurrently of interestin sys- tematics:(1) the treatmentof multiple data setsin phylogeneticanalysis, (2) a priorianalysis and differentialweighting of moleculardata, and (3) the reliabilityof molecularversus mor- phologicaldata in phylogeneticanalysis. Problems in recoveringphylogenetic signal caused by rapidly changingsites in the moleculardata were not solvedby combiningdata sets. Differentiallyweighting saturated partitions of the sequencedata, prior to phylogenetic analysis,provided a phylogenycongruent with morphologicalanalysis. Molecular data pro- vide substantiallymore informative characters than morphological data. However, morpho- logicaldata provide a higherproportion of unreversedsynapomorphies. A reclassification of the family basedon the phylogenyresults in two subfamilies:(1) the Herpetotherinae, (forest-falcons[Micrastur] and LaughingFalcon [Herpetotheres cachinnans]); and (2) the Fal- coninae,which includes the tribesFalconini (Spot-winged Falconet [Spiziapteryx circumcinc- tus],pygmy-falcons [Polihierax], falconets [Microhierax], and the genusFalco) and Caracarini (caracaras).The phylogenyalso indicates that two genera,Daptrius and Polihierax, are poly- phyletic,and thesetwo are split.Finally, a biogeographichypothesis derived from tl•ephy- logenyimplies that the origin and earlydiversification of thefamily occurred in SouthAmer- ica. Received12 November1997, accepted18 June1998. THE FAI•C¸NIDAE,one of three families in the genera:the four caracara genera, Micrastur (for- orderFalconiformes (the diurnal birds of prey), est-falcons),Herpetotheres (Laughing Falcon) includessome of the fastestand mostspectac- and Spiziapteryx(Spot-winged Falconet). The ular birds in the world (Brown and Amadon relationshipsof the latterthree genera histori- 1968).Although the familyis renownedfor the callyhave been problematic (Sharpe 1874, Gur- huntingability of its species(e.g. the Peregrine ney 1894,Swann 1922, Peters 1931). The place- Falcon[Falco peregrinus]), foraging habits with- ment of thesegenera with the caracaras(Ama- in thefamily are diverse. Thus, the Neotropical don and Bull 1988) is in conflictwith results caracaras(Daptrius, Milvago, Polyborus,and from four cladisticanalyses: (1) an osteological Phalcoboenus)are scavengersthat subsistmain- study (Becker1987; Fig. 1A), (2) a preliminary ly on carrion or invertebrates. morphologicalanalysis (Kemp and Crowe In additionto adaptationsrelated to foraging 1990;Fig. 1A), (3) an analysisbased on syrin- habits, the four caracaragenera share other gealmorphology (Griffiths 1994a; Fig. lB), and morphologicaltraits (Friedmann 1950) and his- (4) an analysisbased on cytochrome-bsequenc- toricallyhave been considered to be closelyre- es (Griffiths 1997;Fig. 1C). Basedon Griffiths lated (Sharpe1874, Gurney 1894, Swann 1922, (1994a),the AOU (1998)reclassified the family, Peters1931). Classification of the othergenera placing Herpetotheresand Spiziapteryxwithin in the familyhas been less stable (Sharpe 1874, the Falconinae and Micrastur in its own sub- Gurney 1894, Swann 1922, Peters1931). Ama- family. don and Bull (1988)allocated the 10 currently In thispaper, I reanalyzethe syringealdata, recognizedgenera into two subfamilies.The incorporatingnew information.Having collect- Falconinaeincluded the speciosegenus Falco ed both morphologicaland moleculardata, I and the smallestdiurnal raptors, Polihierax then examinea controversialissue in phylo- (pygmy-falcons)and Microhierax(falconets). geneticinference, the appropriateanalysis of The Polyborinaeincluded seven Neotropical multiple data sets.This controversyspans a continuum of ideas. At one end is the idea that E-mail:[email protected] data setsshould be analyzedseparately. The 116 January1999] FalconidaePhylogeny 117 A nentsof totalevidence propose giving all char- Microhierax and Polihierax actersequal weight initially in phylogenetic • Falco analysis.Assessments of characterreliability Caracaraspecies derivedfrom phylogeneticinference (i.e. suc- Micrastur cessiveapproximations; Farris 1969, 1989; Car- penter1988) can thenbe usedto weightchar- t HorpotothorosSpiziaptoryx actersdifferentially (a posterioriweighting). A prioridifferential weighting is criticizedfor in- B • Falco curring unwarrantedassumptions about pro- Microhiorax cessor requiringpartitions of datafor weight- Polihioraxsomitorquatus Spiziaptoryx ing that maybe arbitrary(Eernisse and Kluge Polihieraxinsignis 1993, Brewer and DeSalle 1994, Chippindale Horpotothoros and Wiens 1994). Caracaraspecies As part of the empiricalexploration of the Micrasturspecies analysisof multipledata sets, I examinethe ef- Outgroups fectsof differentialweighting on phylogenetic inference.I then comparethe morphological and moleculardata. The phylogenyinferred c • Falco from thesedata is usedto reclassifythe Falcon- Microhiorax idaeand two generawithin thatfamily. Finally, Polihioraxsomitorquatus the phylogenyprovides a frameworkfor dis- Spiziapteryx cussingthe biogeographyof the family. Caracaraspecies MATERIALS AND METHODS MicrasturHorpotothorosspecies Accipiter Morphologicaldata.--Characters were derived from variation in syringeal supporting elements,mem- FIC. 1. Phylogenetichypotheses inferred from branes,and muscles(Griffiths 1994a). Supporting el- cladisticanalyses of the Falconidae.(A) Phylogeny ementsinclude ringlike elements on the tracheaand inferred from osteologicaldata (Becker1987) and a bronchi(A and B elements;Ames 1971 ), the pessulus, preliminaryanalysis of skinsand characters from lit- and accessorycartilaginous structures. Hemology of erature(Kemp and Crowe1990). (B) Phylogenyin- the ringlikeelements was traditionallybased on the ferredfrom syringealmorphology (Griffiths 1994a). relativeposition of thesestructures to the tracheo- (C) Phylogenyinferred from differentially weighted bronchialjunction (King 1989). This analysis postu- cytochrome-bsequences (Griffiths 1997). lateshomologous elements following Ames' (1971) definitionsof syringealstructures (Griffiths 1994b). Dataon variationin syringealmorphology for two congruenceof phylogeniesinferred from each specieswere addedto the originaldata of Griffiths dataset (taxonomiccongruence) then provides (1994a).The first, Accipiterstriatus (Sharp-shinned a measureof the reliabilityof the phylogenies Hawk; AMNH 18761), was substituted for Gampso- (Lanyon1993, Miyamoto and Fitch 1995).At nyx swainsoniito be consistentwith the molecular the oppositeend is the ideathat multipledata data.The second,Herpetotheres cachinnans (LSUMNS setsshould be combinedfor phylogeneticanal- 123200),recently became available. Because the Her- ysis (total evidenceor charactercongruence; petotheressyrinx used to codecharacters for theorig- Kluge 1989). inal analysis(Griffiths 1994a) had been damaged, Between these two extremes, proposed this new specimenwas examined and the resulting methodsfor analyzingmultiple data setsin- information used to recede two of the characters. Character16, the modificationof the ends of the B1 clude: (1) conditional combinationof data sets, element,changed from one to zero.Character 3, dor- i.e. combinationonly if thedata sets are not sig- sal fusionof the tympanum,changed from one to nificantlyheterogeneous (Bull et al. 1993,Huel- two. In addition,three characters (characters 5, 6 and senbecket al. 1996); or (2) unconditionalcom- 7) that were originallycoded as binary representa- binationof data setswith differentialweight- tions of alternative character states were receded as ing of charactersto accommodateheterogene- one unordered multistate character. ity (Chippindaleand Wiens1994). Differential Syringealcharacter descriptions with thesemod- weightingis, in itself, controversial.Propo- ificationsare presented in Appendix1. Thefinal data 118 CAROLES. GRIFFITHS [Auk, Vol. 116 TABLE1. Speciesincluded in the phylogeneticanalyses. Species Combinedanalysis Morphological Molecular Milvago chimachima * * * M. chimango no * no Polyborusplancus * * * Phalcoboenus australis * * * Daptriusater * * * D. americanus * * * Spiziapteryxcircumcinctus * * * Micrasturgilvicollis * * * M. semitorquatus * * * Polihieraxinsignis no * no P. semitorquatus * * * Microhieraxerythrogonys * * * Herpetotherescachinnans * * * Falcoberigora no * no E sparverius * * * E mexicanus no * no E peregrinus * * * E rufigularis no * no E biarmicus no * no E columbarius no * no E cenchroides no * no E vespertinus * no * E femoralis * * * Accipiterstriatus * * * Otus asio no * no Pelecanus onocrotalus no * no matrixfor the reanalysisconsisted of 25 taxaand 23 able.All 10 currentlyrecognized genera were sam- characters,six of which were multistate(Appendix pled for both molecularand syringealcharacters (Ta- 2). Transformation series for multistate characters ble 1). However,taxon sampling was not identicalbe- were proposedif adjacentderived states were simi- tweenthe two datasets. Some species sampled with- lar, and eachsucceeding state was a modificationof in the genusFalco varied betweenthe two, and no the previousstate; that is, the derivedstates formed tissuesamples of Polihieraxinsignis (White-rumped a nestedset of synapomorphies.Multistate charac- Pygmy-Falcon)were