The Auk 113(1):74-93, 1996

A PHYLOGENETIC ANALYSIS OF MODERN POCHARDS (: AYTHYINI)

BRADLEY C. LIVEZEY Sectionof ,Carnegie Museum of Natural History,4400 ForbesAvenue, Pittsburgh, Pennsylvania15213, USA

ABSTRACT.--Aphylogenetic analysis of modern pochards(Aythyini) was performed using 99 charactersof the skeleton,trachea, natal plumage,and definitive integument.Three short- est trees were found (length = 148; consistencyindex for informative characters= 0.68) which: (1) placedMarmaronetta as the sistergroup to other members;(2) defined a basalclade comprising as sister groups Rhodonessacaryophyllacea + rufinaand N. peposaca+ N. erythrophthalma;and (3) defined as the sistergroup to the precedingclade all other pochards, in which the three redheads(Aythya valisineria, and the sisterspecies A. ferinaand A. americana) are the sister group to the mutually monophyletic white-eyes (A. australis,A. innotata,and the sisterspecies A. nyrocaand A. baeri)and scaup(in order of increasinglyclose relationship, A. novaeseelandiae,A. collaris, A. fuligula,A. marila,and A. affinis).The three shortesttrees differed only in the topology among the white-eyes. These nodes, and that supporting the sister relationship between N. peposacaand N. erythrophthalma,were the only nodes not conservedin a majority of bootstrappedreplicates; Bremer (decay)indices provided similar assessmentsof empirical support. Evolutionary trends in body mass, clutch size, preferred nest site, diel activity pattern, and biogeographicpatterns are evaluatedin the contextof this phylogenetic hypothesis. Quantitative comparisonswith previously proposedphylogenetic hypotheses,particularly that of Johnsgard,are made using constrainedsearches based on these data, and a revised classificationof the Aythyini is proposed.Received 16 June1995, accepted6 September1995.

POCHARDSOR BAYDUCKS (Aythyini), one of of Aythyini, the Pink-headedDuck (Rhodonessa four tribes of the subfamily , comprise caryophyllacea),was extirpated in the early 17 modern speciesof waterfowl (Delacourand twentieth century (Bucknill 1924,Wright 1925). Mayr 1945, Delacour 1959, Wolters 1976, Liv- In addition, the MadagascanWhite-eye (Aythya ezey 1986).The Aythyini range in size from the innotata)is consideredendangered and may have Marbled (Marrnaronettaangustirostris; mean becomeextinct within the last decade(Young body mass <500 g) to the Canvasback(Aythya and Smith 1989, Wilm• 1993, 1994, S. M. Good- valisineria;1,200 g). Most speciesregularly em- man pers. comm.), and seriousdeclines have ploy diving during foragingand are character- beenreported in the Marbled Duck(Green 1993), ized by moderately heavy wing loadingsand as well as the Ferruginous(A. nyroca)and Si- significant specializationfor subaquaticloco- berian (A. baeri)white-eyes (Collar et al. 1994, motion (Miillenhoff 1885, Townsend 1930, Poole Tucker and Heath 1994). 1938, Woolfenden 1961, Raikow 1970, 1973, With the exception of the tribal assignment Hoerschelmann 1971, Livezey 1986, Tome and of the Marbled Duck (Johnsgard1961a, b, c) and Wrubleski 1988, Faith 1989). Members of the the comparatively late inclusion of the Pink- tribe are distributed in both the Northern and headed Duck within the Aythyini (Johnsgard Southern hemispheres,with the greatestdiver- 1961a,c, Woolfenden 1961,Humphrey and Rip- sity of membersoccurring in temperateEurasia ley 1962),the notion that the Aythyini formed (Weller 1964a). A modest fossil record of the a natural group has receivedvirtually unani- tribe has been described (Brodkorb 1964, How- moussupport by systematistsfor almosta cen- ard 1964), but limited material and inadequate tury (Salvadori1895, Phillips 1925,Peters 1931, diagnosesof the describedtaxa render ques- Delacourand Mayr 1945,Boetticher 1952, Ver- tionable most of the earliest records assigned heyen 1953, Delacour 1959, Johnsgard1961a, to the tribe (Livezey and Martin 1988). Most 1978,1979, Livezey 1986).Johnsgard (1961a: 80) speciesof Aythyini are migratory and breed describedthe Aythyini as "a remarkably ho- primarily near permanentbodies of fresh water mogeneousgroup of species,behaviourally as (Delacour 1959, Weller 1964a, b). One species well as anatomically."Although arrangements

74 January1996] Phylogenyof Pochards 75

of taxa within the tribe have been compara- alyzed; therefore, all were merged for purposesof tively stable in recent decades (Delacour and character description and phylogenetic inference. Mayr 1945, Delacour 1959, Johnsgard1961a, Commonnames of the Aythyini employedin the text, 1978,1979), explicit investigationsof relation- a few of which differ from thoselisted by Johnsgard ships among Aythyini have been limited to: (1979),conform with the phylogeneticrelationships inferred here and the resulting classification. intuitive phenetic comparisonsof behavioral Specimens.--Skeletonsand skin specimensof adults characteristics(Delacour and Mayr 1945,Johns- of the 17 speciesof Aythyini (and outgroups,dis- gard 1961a, 1965) and of syringeal bullae cussedbelow) were studied directly for character (Johnsgard1961c); phenetic comparisons of al- analysis.Tracheae of adult maleswere studiedas part lozyrnes (Brush 1976, Numachi et al. 1983, Pat- of skeletal specimensfor most species;separately ton and Avise 1985)or uropygialsecretions (Ja- mounted tracheaeof a number of speciesalso were cob and Hoerschelmann1993); phenetically studied, mostly at the Wildfowl and Wetlands Trust rooted,cladistic analyses of mitochondrialDNA (WWT). The mounted trachea of a male Pink-headed (Kessler and Avise 1984, 1985; also see Omland Duck illustrated by Garrod (1875) was examined at 1994); and a cladisticanalysis of the four in- the BritishMuseum (Natural History). The tracheaof a male MadagascanWhite-eye was studied in a fluid- cluded genera using morphologicalcharacters preserved specimen at the British Museum (Natural (Livezey 1986). Using DNA-DNA hybridiza- History); a completeskeleton of this species,not listed tion, Madsen et al. (1988) included only one by Wood and Schnell(1986), was borrowed from the memberof the tribe, and Sibley and Ahlquist Field Museum of Natural History (FMNH). Speci- (1990) included no Aythyini in their studies; mensof downy young of all speciesbut the extinct the companion classificationby Sibley and Pink-headedDuck (undescribed)were compared;na- Monroe (1990), which did not include tribal tal specimensof the MadagascanWhite-eye were groupingswithin the Anatinae,apparently was availableonly as fluid-preservedbirds. Homologies, taken from existing works. Only Johnsgard states,and basal polarities of characterswere con- (1961a),based on a nonquantitativeassessment firmed using publisheddescriptions and illustrations of plumagesand tracheae(Latham 1798,Eyton 1838, of behavioraland (to a lesserextent) morpho- Garrod 1875,Phillips 1922, 1925,Schioler 1926, Bro- logicalsimilarity, proposed an explicit,species- man 1942,Delacour and Mayr 1945,1946, Kagelmann level hypothesisfor the phylogenyof the Ay- 1951, Delacour 1956, 1959, 1964, Weller 1957, Dzubin thyini. 1959,Johnsgard 1961b, c, 1962, 1965, 1979,Woolfen- In this paper,I describea phylogeneticanal- den 1961, Humphrey and Ripley 1962, Humphrey ysisof the 17 Recentspecies of Aythyini based and Clark 1964, Gillham et al. 1966, Beer 1968, Warner on characters of the skeleton, trachea, and natal 1971,Palmer 1976,Amat 1986,Madge and Burn 1988, and definitive integument.The resulting hy- Wilsonand Ankney 1988,King 1989,1993,McLelland pothesisis used as the basisfor analysisof his- 1989, Marchant and Higgins 1990, del Hoyo et al. 1992, Nelson 1993). torical biogeography,selected comparisons of Definitionof characters.--Iidentified 99 morpholog- life-historical characteristics, and a classifica- ical charactersthat defined or varied within the Ay- tion of modern pochards. thyini: 14 skeletalcharacters (after Livezey 1986),7 trachealcharacters, 9 charactersof natal plumage,and METHODS 69 charactersof the plumage and soft parts of adults (Appendix1). Osteologicaland syringealnomencla- .--Compositionof the Aythyini follows ture follows the recommendations of the Interna- Livezey (1986) and specifictaxa recognizedconform tional Committee on Avian Anatomical Nomencla- with currentlyaccepted classifications (Delacour 1959, ture (Baumeland Witruer 1993,King 1993).Each char- Johnsgard1965, 1978, 1979, AOU 1983).Only three actercomprised a primitive (plesiomorphic)state and speciesof Aythyini areconsidered polytypic: Southern one or more derived (apomorphic)states. Each char- Pochard(Netta erythropthalma), partitioned into Neo- acterwas codedfor all speciesexcept natal characters tropical (nominate) and African races (brunnea);the of the Pink-headedDuck, which were assignedmiss- Australian White-eye (Aythya australis),with conti- ing-datum codes.The resulting 17 x 99 data matrix nental (nominate) and Banks Islands (extima) races (with an additional vector for the hypotheticalan- recognized;and the Greater Scaup (A. marila), with cestor,discussed below) is presentedin Appendix 2. Palearctic (nominate) and Pacific Basin (mariloides) Charactershaving more than one derived statewere formsdistinguished taxonomically. With the possible analyzedas unordered. An effort wasmade to reduce exceptionof the SouthernPochard (which showsweak multistate characters(characters having more than differentiationin plumageand meritsfurther study), one derived state)to two or more binary characters these subspeciesdid not differ in the charactersan- to simplifyanalyses. Characters for which the derived 76 LIVEZEY [Auk,Vol. 113 state(s)was possessedby single species(autapomor- genera,and subgenera--were basedon senior taxaof phies) were included in the analysisto confirm the appropriaterank, in part basedon the classifications monophyly of terminal taxa (in the same way that of Boetticher(1942,1952) and the synonomiesof Phil- synapomorphiesunite more inclusive groups) and lips (1922, 1925),Brodkorb (1964), and Wolters(1976). permit estimatesof evolutionarydivergence. Mappingof attributes.--Selectedgeneral ecological Outgroups,derivation of trees,and classification.--As and functional attributesof evolutionaryinterest var- for the working assumptionof monophylyof the in- ied among the Aythyini. Theseattributes--including group, outgroupswere selectedon the basisof inter- bodymass, clutch size, nest-site selection, diel activity genericrelationships inferred by Livezey(1986, 1991); pattern,and dietary preferences--werecompiled for these included several speciesof Anatini (sensuLiv- the Aythyini based on the information taken from ezey 1991; primary exemplarswere Cairinamoschata, specimensand the literature (Wright 1925,Townsend Marecaamericana, Anas platyrhynchos), as well as basal 1930, Cottam 1939, Delacour 1959, All 1960, Sch•n- Oxyurini (Heteronettaatricapilla) and Mergini (Polys- wetter 1961, Weller 1964b, c, d, Kear 1970, Raikow ticta stelleri).The hypotheticalancestor, a vector of 1973, Prestwich 1974, Bellrose 1976, Palmer 1976, primitive character states based on outgroup com- Cramp and Simmons1977, Johnsgard 1978, Brown et parisons,was used to root the phylogenetic tree(s). al. 1982,Eadie et al. 1988,Madge and Burn 1988,Roh- This method providesa single root for the ingroup wer 1988, Tome and Wrubleski 1988, Rohwer and (seeLivezey 1986,1989, 1995a, b, c, Livezeyand Mar- Freeman 1989, Scott and Clutton-Brock 1989, Mar- tin, 1988),while avoidinganalytical digressions con- chant and Higgins 1990,Amat 1991,del Hoyo et al. cerning relationships among outgroups (considered 1992, McNeil et al. 1992, Dunning 1993). Mean body elsewhere; Livezey 1996). Empirical support for massesof specieswere estimatedby the unweighted monophyly of the ingroup is comensuratewith the mean of the mean masses for adults of the two sexes number of unambiguoussynapomorphies for the in- separately.Sexual size dimorphism was evaluated us- group taxa relative to the hypotheticalancestor. ing the ratio of the meanbody massof malesdivided Treeswere constructedcladistically under the prin- by the mean body massof females.Relative clutch cipleof globalparsimony (Wiley 1981),using the phy- masswas defined as the product of mean clutch size logenetic software PAUP 3.1 (Swofford 1993); sup- and mean egg massdivided by the mean body mass plementarytopological analyses and printing of trees of an adult female. Data for many attributes of the were performed on MacClade 3.01 (Maddison and Pink-headedDuck and MadagascanWhite-eye were Maddison 1992). I used the branch-and-bound algo- not available, and reliable estimatesof some param- rithm to find the shortest tree(s). The skewnesssta- eterswere not attainablefor severalothers (e.g. "Net- tistic (g•) for the distribution of tree lengths, a crude ta" peposaca,Aythya baeri). I employeda posteriorimap- indicatorof phylogeneticsignal (Hillis 1991,K•illersj• pings of selectedecomorphological attributes on trees et al. 1992), was calculated based on 1,000 trees ran- using MacClade 3.01 (Maddison and Maddison 1992). domly generated from the matrix. A branch-and- bound bootstrappingprocedure was employed to generate 100 topological replications. Support for RESULTS brancheswithin the final tree was summarizedby a 50% majority-ruleconsensus tree of these 100 repli- Most-parsimonioustopologies.--Three most- catetrees. This applicationof bootstrappingwas used parsimonioustrees of length 148 were discov- as an index to the empirical supportfor branchesin ered; unambiguous character changes, those the shortesttree(s) but, becauseof the likely inter- supporting the branchescommon to all three dependenceof characters,was not used for strict probabilisticinferences (Felsenstein 1985, Sanderson trees, are detailed in Figure 1. Summary statis- 1989). The Bremer or "decay" index (Bremer 1988), tics for these most-parsimonioustrees were: which equalsthe number of additional stepsrequired consistencyindex, 0.750; consistencyindex ex- to disrupta given node,was calculatedfor eachnode cluding uninformative characters,0.684; reten- using conversetopological constraintsand random tion index, 0.818; rescaled consistencyindex, addition of taxato avoid local optima (Swofford1993); 0.613.Topological differences among these three the index for the most-basalnode was approximated trees were limited to the relationshipswithin by including two duplicateancestral taxa in the con- one clade involving three speciesor species strained analysis.Topological constraints also were groups--Aythya innotata,A. australis,and the used to assessthe additional stepsrequired to accom- coupletA. nyroca+ A. baeri--depictedas a tri- odatepreviously proposed phylogenetic hypotheses using the present data set. chotomyin the detailed tree (Fig. 1). The skew- Phylogeneticclassification.--The resulting phyloge- nessstatistic (g•) for 1,000trees randomly gen- netic tree(s) formed the basis for a Linnean classifi- erated for the matrix was -0.829. A majority- cation using the methodsdescribed by Wiley (1981). rule consensustree of 100 bootstrappedrepli- Unconventional taxonomic ranks--subtribes, super- catesrevealed that the sister-grouprelationship January1996] PhylogenyofPochards 77

61 $ 7 5 50 10 26

Fig.1. Detailedtopology showing unambiguous character changes supporting branches common to three most-parsimoniousphylogenetic trees for Aythyinibased on 99 morphologicalcharacters. Labels identify skeletal(s), tracheal(t), natal(n), and definitive(d) characters;see Appendices 1 and 2 for definitionsand distributions of states.

betweenthe Rosy-billedPochard (Netta pepo- rufina);and the Rosy-billedand Southernpo- saca)and (N. erythrophthalma)chards (Fig. 1). had only modestsupport (Fig. 2). Similarpat- The remaining Aythyini comprised three ternsof empiricalsupport were indicatedby clades:the "redheads"(three species, five sup- the Bremer indices for nodes common to the porting synapomorphies),the "white-eyes" shortesttrees (Fig. 3). (four species,five unambiguoussynapomor- Phylogeneticinferences.--Monophyly of the phies), and the "scaup"(five species,four un- tribewas supported by four unambiguoussyn- ambiguoussynapomorphies). Within the red- apomorphies--one skeletal, two of the natal heads,the sistergroup of the other two clades, plumage,and one of the definitive plumage the Canvasback(A. valisineria)was hypothe- (Fig. 1). Members of the tribe exclusiveof the sizedon the basisof a singleunambiguous syn- Marbled Duck were determined to be mono- apomorphy to be the sister group of a clade phyleticon the basisof 20 unambiguoussyn- comprising the Redhead (A. americana)and Eur- apomorphies--eight skeletal,four tracheal,two asian Pochard(A. ferina).Relationships within natal,and sixof the definitiveintegument (Fig. the white-eyes remain unresolved,but a sister 1). This large cladecomprised two monophy- relationship between the FerruginousWhite- leticsubgroups, one includingthe four species eye (A. nyroca)and the SiberianWhite-eye (A. of "stem"pochards and the otherincluding all baeri)was inferred in all threeof the most-par- otherAythyini. The four "stem" pochards com- simonioustrees (Fig. 1) and proved robustwith prise two coupletsof sisterspecies: the Pink- respect to bootstrapping (Fig. 2). The three headedDuck and the Red-crestedPochard (N. equallyparsimonious topologies for the white- 78 LIVEZEY [Auk, Vol. 113

angustirostris angustirostris caryophyllacea caryophyllacea rufina [4] rufina peposaca peposaca erythrophthalma erythrophthalrna

fedna ferina

lOO americana valisineda americanavalisinerfa australis

nyroca 74 nyroca I, baerf 941721 innotata innotata novaeseelandiae novaeseelandiae 57[. coilads baericoilads ful•ula fuligula marfla ß affinis affinismadla Ancestor Ancestor Fig. 2. Majority-rule consensustree of 100 boot- Fig. 3. Strict-consensustree for three shortest strappedreplicates for Aythyini. Percentagesof rep- phylogenetictrees for Aythyinishowing Bremer (de- licatesin which eachnode wasconserved are given. cay) indicesfor eachnode. eyeswere: (1) A. innotataand A. australisas sister eral different evolutionary patterns having species,together composing the sistergroup of varying degreesof phylogeneticconservatism the clade A. nyroca+ A. baeri;(2) A. innotataas within the tribe (Fig. 4). Mean body massvaried the sistergroup of A. australisand the cladeA. significantly among member species,which nyroca+ A. baeri;and (3) A. australisas the sister tended to fall into three major size groupsused group of A. innotataand the cladeA. nyroca+ for mapping.A primitive small body size is re- A. baeri.Within the scaup(Fig. 1), the New Zea- tained by Marrnaronetta,but the distributionof land Scaup (A. novaeseelandiae)was inferred to medium and large body masseswithin the three be the sister-groupof the remaining species; major clades in the remaining Aythyini pre- within the latter, the Ring-neckedDuck (A. col- vents the determination of ancestral states for laris)was placed as the sisterspecies of the Tuft- much of the tribe; notable, however, are the ed Duck (A. fuligula)and the clade comprising substantial, independent reductions in body the Greater Scaup(A. marila)and LesserScaup massundergone by the EurasianPochard and (A. affinis).The latter three-speciesgroup was New Zealand Scaup (Fig. 4A). defined by five unambiguoussynapomorphies Mean clutch size in the tribe evidently un- (Fig. 1). At least one unambiguousautapomor- derwent several independent decreases:(1) in phy defined all speciesexcept the Madagascan the Pink-headed Duck, although data are few White-eye (Fig. 1). Severalspecies were highly for this species;(2) in the Canvasbackand Eur- autapomorphic,notably the Pink-headedDuck asian Pochard,perhaps homologouslywith an (7 autapomorphies), Red-crested Pochard (8), autapomorphicreversal in the highly nest-par- Rosy-billedPochard (6), and Ring-neckedDuck asitic Redhead; and (3) in the New Zealand (7). Scaup,coincident with a decreasein body mass Ecomorphologicaltrends.--A mapping of se- (Fig. 4B). Preferred nest sites showed at least lected attributes on one of the shortest trees for two comparativelymarked transitionswithin the Aythyini (arbitrarily selected)revealed sev- the tribe (Fig. 4C): (1) a shift from ground sites January1996] Phylogenyof Pochards 79 to thosein emergentvegetation in the ancestor encesin feeding anatomy(Kehoe and Ankney of the tribe exclusive of Marmaronetta; and (2) 1985, Kehoe and Thomas 1987, Lagerquistand and a subsequentreversal to ground sitesin the Ankney 1989), however, and the dietary im- Greaterand Lesserscaups, with the three other, portanceof invertebratesincreases during the more basal membersof this clade showing in- breedingseason in mostAythyini (Bartonekand termediatepreferences. Diel activitypattern ev- Hickey 1969). idently underwent two changesof like direc- tion within the tribe; a shift from plesiomorphic DISCUSSION diurnal activity to crepuscularhabit is hypoth- esizedfor the ancestorof the tribe, followed by Problematiccharacters and groups.--Several in- a shift to largely nocturnal feeding in the an- ferencesin the presentanalysis differ from tra- cestor of the clade comprising the redheads, ditional placements(Peters 1931, Delacour and white-eyes, and scaups(Fig. 4D). Mayr 1945, Delacour 1959, Johnsgard1961a, In accordancewith the homogeneityof po- 1965, 1978, 1979) and, in one instance, with the chards cited by Johnsgard(1961a), however, generic relationshipsproposed in my earlier many ecomorphologicalattributes that vary work (Livezey 1986).The inclusionof the Mar- within other tribes of showed bled Duck asthe sistergroup of other pochards, negligible variation in the Aythyini. For ex- the intertribal "linking" position of which was ample, egg mass averages 50 to 65 g for the first suggestedby Johnsgard(1961b), is strongly Aythyini, exceptionsbeing the Marmaronetta(31 supportedby this analysis(Fig. 1). The mono- g) and the sisterspecies Aythya nyrocaand A. phyly of the "stem" pochardsinferred herein baeri (43 g). Relative clutch mass showed re- agreeswith the grouping of these species(ex- markableuniformity in the group,with species cluding the Pink-headed Duck, consideredan retaining the primitive averageof 50 to 70% of aberrant dabbling duck) as "narrow-billed po- mean body massof females.Sexual size dimor- chards"by Delacour (1959). Placementof the phism also varied little within the tribe, with Pink-headedDuck within a cladeof "stem" spe- membersretaining the evidently primitive mean cies and as the sisterspecies of the Red-crested ratio of 1.05 to 1.15. Sexual dichromatism, the Pochard (Fig. 1), instead of as the sister group presenceof which is probablyprimitive for the to the Aythyini exclusive of Marmaronetta Aythyini, is absent (probably autapomorphi- (Johnsgard1961a, Livezey 1986), also was un- cally lost)only in basalMarmaronetta. Moderate expected.The unique autapomorphiesof the occurenceof intraspecificand interspecificnest Pink-headedDuck, in particularthe bright pink parasitismcharacterizes the Aythyini and most coloration of the head, undoubtedly led to its other Anseriformes (Andersson 1984, Eadie et assignmentto a monotypic genus. The mono- al. 1988, Rohwer and Freeman 1989, Amat 1991); phyly of the "typical" pochardsconfirmed here only the exceptionallyhigh frequencyfor the (Fig. 1) conforms with the grouping of these Redheadis noteworthy (Weller 1959). speciesas "broad-billed pochards" by Delacour Diving habit showsa simple, weakly defined (1959). trend within the tribe, in which the presumably The traditional view of a sister-grouprela- primitive relianceon surfacefeeding is retained tionshipbetween the Canvasbackand Eurasian by Marmaronetta,a co-relianceon surfacefeed- Pochard,either implied by taxonomicsequenc- ing and diving characterizesthe four speciesof es(Delacour and Mayr 1945,Delacour 1959, Sib- stem pochards,and a primary reliance on div- ley and Monroe 1990) or explicitly indicated ing unites the remaining membersof the tribe. (e.g. Johnsgard1961a, 1965, 1978, 1979),differs A similarlyweak but topologicallydistinct pat- from the marginallysupported arrangement in- tern in dietary preference is evident, in which ferred here (Fig. 1). The monophylyof the four the primitive general preferencefor vegetable speciesof white-eye confirmed herein was rec- material (with secondary use of invertebrate ognizedexplicitly by Delacourand Mayr (1945), prey) is retainedby all membersof the Aythyini but the poor resolution within this clade (Figs. exceptthe three most-derivedspecies of scaups 1 and 2) representsan only marginal improve- (Aythyafuligula, A. marila,and A. affinis),which ment over the vague and contradictoryarrange- tend to favor invertebrateprey over vegetable ments of speciessuggested by other investiga- items. This subtle differencein food preference tors (e.g.Delacour 1959,Johnsgard 1961a, 1978). is reflectedonly in part by interspecificdiffer- The composition and interspecific relation- 80 LIVEZEY [Auk,Vol. 113 /

ß ß ß ß ß []

(A) Body Mass (g) r-• < 700 • 700-1000 • > 1000 •equivocal

(B) Clutch Size [----] 6- 8 •9-11 • equivocal

Fig. 4. Tracesof four selectedecomorphological attributes on one of three most-parsimoniousphylogenetic trees for Aythyini: (A) mean body mass,(B) mean clutch size, (C) preferred nest site, and (D) diel activity period. See Appendices1 and 2 for definitions and distributionsof states. January1996] PhylogenyofPochards 81

(C) Nest Site • upland • over-water ',";,,:;:;•uncertain • equivocal

ß ß ß ß ß ß ß ß

(D) Activity Pattern [--] diurnal • crepuscular • nocturnal •equivocal

Fig. 4. Continued. 82 LIVEZ•h' [Auk, Vol. 113 shipsof the five speciesof "scaups"in the pres- than is A. novaeseelandiaerequired six extrasteps. ent analysis differs in several comparatively Aythya collaris remains, however, somewhat contentious ways from current arrangements. enigmaticin its combinationof characterstates; The relationshipsinferred here, in which Ay- the speciesis unique by reversalor homoplasy thya collarisis interposed between A. novaesee- within its five-speciesclade in three characters landiaeand A. fuligulain a grade subtendingthe of the natal and definitive plumages(Fig. 1), as sister speciesA. affinisand A. marila (Fig. 1), well ascombining significantintraspecific vari- agrees with the sequenceof speciesgiven by ation in several other characters with a sub- Delacourand Mayr (1945);these authors, how- stantial number of autapomorphies (Appendi- ever, implied the monophyly of the first three ces I and 2). speciesby bracketingthem asa "superspecies." Congruencewith behavioralcharacters.--Loss The placementsof A. collarisamong the "scaups" (mostspecies) or great reductionin frequency or asespecially closely related to A. fuligulawere (possiblyin somestem pochards)of the "de- among the earliest taxonomicarrangements of crescendocall" by females,typical of dabbling this group (e.g. Salvadori 1895, Hollister 1919, , unites the Aythyini (Johnsgard1960a, Peters 1931, Boetticher 1942, 1952, Delacour 1961a,b, 1962,1965, McKinney 1978).Similarly, 1959), and the similarities of appearance be- "head-pumping" precopulatorydisplays are ab- tween the two speciesled several early natu- sentor rudimentaryin the Aythyini (including ralists to confuse the species(Mendall 1958). Marmaronetta),a distinction from the dabbling Johnsgard(1961a, 1965, 1978, 1979), however, ducks (Johnsgard 1965). Other courtship dis- concludedthat A. collarisis more closelyrelated plays of pochards,most either sharedwith dab- to the "redheads" (A. valisineria, A. americana, bling ducks(and presumablyplesiomorphic) or and A. ferina),citing similaritiesof natal plum- for which clearly homologous displays are ages, trachea, and courtship behavior. known in other tribes(Johnsgard 1960b, 1965), Quantitative comparisonwith a tree figured are homogeneouswithin the tribe and include by Johnsgard(1961a) revealed that adoption of displaysby males("kinked-neck call," "cough- his phylogeny using the present data set re- ing," "turning the back-of-the-head," "head- quired an additional 33 steps,a 22% increasein throw," "sneaking,"and "neck-stretching"),by total length of the tree. This comparisonas- females ("inciting calls"), and by both sexes sumes that the tree depicted by Johnsgard ("preening behind the wing"). (1961a: fig. 6) can be interpreted as a formal Interspecifichybridization.--Possibly related at phylogenetic tree, an assumptionthat is prob- least in part to the homogeneityof courtship lematic for two reasons: (a) inclusion of Mar- displayswithin the Aythyini, interspecifichy- maronettawith the pochardsis not shown in his bridization is comparativelyhigh amongmem- tree, but is suggestedin text, whereasthe genus bers of the tribe (Johnsgard1960c, Scherer and wasdepicted as the sistergroup of the dabbling Hilsberg 1982).The frequencyof hybridization ducksby Johnsgard(1968: fig. 1),but wasshown among pochardsand the confusingphenotypes later as the sister group of other pochardsby of hybrid progeny have prompted repeated Johnsgard(1978: xviii); and (b) the genusNetta commentary (Salvadori 1895, Johnsgard1960c, delimited by Johnsgard (1961a) is explicitly Milstein 1979, Scherer and Hilsberg 1982, polyphyletic, two of three of the member spe- Smallshire 1986), and anatomical comparisons cies (peposacaand erythrophthalma)being de- of hybrids include plumage patterns (Gillham picted asbasal members of two different, graph- et al. 1966,Madge and Burn 1988) and tracheae ically overlappinggroups. Four additional steps (Beer 1968). Interspecifichybridization tradi- alone are required for the placement of Rho- tionally has been interpreted as the breakdown donessaas the sister group of the tribe exclusive of evolutionarily "adaptive" isolating mecha- of Marmaronetta.Imposition of monophyly of nisms(Johnsgard 1963). An alternative view, in the three speciestraditionally included in Netta which such "mechanisms" reflect the hierar- required five additional stepsin the tree. The chical accumulationof morphological and be- placement of A. collarisas the sister group of havioral characters of undetermined selective the three speciesof "redhead" by Johnsgard value within lineages, has been suggestedfor (1961a) entailed an increasein total tree length other tribes of waterfowl (Livezey 1991, 1995a, of three steps,and his placementof A. fuligula b, c). The frequency of hybridization and the as lessclosely related to A. marilaand A. affinis viability of hybrid progeny alsohave been con- January1996] Phylogenyof Pochards 83

T^BI•E1. Phylogeneticclassification of modern Ay- the Aythyini represent a very closely related thyini. group of species,with two being the maximum number of genera that can be reasonablyal- Order Anseriformes(Wagler, 1831) Suborder AnserersWagler, 1831 lowed." However, interspecifichybridization Family Anatidae Vigors, 1825 reflects a primitive intercompatibility of lin- Subfamily Anatinae Swainson,1837 eagesand, therefore,does not reflectphyloge- Tribe Aythyini Delacour& Mayr, 1945.--Pochards netic relationship (Livezey 1991),and the num- Subtribe Marmaronetteae, new taxon ber of genera to be recognized within a tribe Genus Marmaronetta Riechenbach, 1853 hinges primarily on investing the greatest Marmaronettaangustirostris (M•n•tries, 1832).--Marbled Duck amountof phylogeneticinformation in the cho- Subtribe Rhodonesseae Boetticher, 1952.--Stem sen taxonomy (Wiley 1981). Moreover, in con- (narrow-billed) pochards trast with the diversity of intergeneric hybrids Genus RhodonessaReichenbach, 1853 (>Netta known for the Aythyini generally, hybrids be- Kaup, 1859) tween the sisterspecies A. marilaand A. affinis Rhodonessacaryophyllacea (Latham, 1790).- Pink-headed Pochard in the wild have not been reported, although Rhodonessarufina (Pallas, 1773).--Red-crest- difficulties in identification of the latter may ed Pochard accountfor the absenceof reports (Madge and GenusMetopiana Bonaparte, 1856 (>Phaeoaythia Burn 1988). Delacour, 1937) Metopianapeposaca (Vieillot, 1816).--Rosy- Biogeographicalpatterns.--The collective dis- billed Pochard tributional limits of the members of the Ay- Metopianaerythrophthalma (Wied, 1832).- thyini encompass:(!) a broadband of temperate Southern Pochard habitats throughout the Northern Hemisphere, Subtribe Aythyeae Boetticher,1952.--True reaching a maximal diversity in the central Pa- (broad-billed)pochards GenusAythya Boie, 1822.--Typical pochards learctic; and (2) a more fragmented, Southern SubgenusAristonetta Baird, 1858.--Redheads Hemisphere range including much of South Aythya valisineria(Wilson, 1814).--Canvas- America, southernmostAfrica (including Mad- back (Canvas-backed Pochard) agascar),and the Australasian region (Weller Aythyaferina (Linnaeus, 1758).--Eurasian Pochard 1964a).Within the context of the present phy- Aythyaamericana (Eyton, 1838).--Redhead logenetic hypothesis(Figs. 1 and 2), a few bio- (Red-headed Pochard) geographicalinferences beyond this broad out- SubgenusNyroca Fleming, 1822.--White-eyes line can be attempted.Several of the most-basal Aythyaaustralis (Eyton, 1838).--Australian members of the tribe--Marbled Duck, Pink- White-eye Aythyainnotata (Salvadori, 1894).--Madagas- headed Duck, and Red-crested Pochard--share can White-eye Palearctic distributions; species in the sister Aythyanyroca (Giildensffidt, 1769).--Ferru- group of the latter two specieshave Neotropical ginousWhite-eye or Neotropical-Africandistributional limits. Of Aythya baeri(Radde, 1863).--Siberian White- the 12 remaining speciesin the tribe, all but eye SubgenusAythya Boie, 1822.--Scaup three are limited to the Northern Hemisphere; Aythya novaeseelandiae(Gmelin, 1789).- the australmembers are the MadagascanWhite- New Zealand Scaup eye, Australian White-eye, and New Zealand Aythya collaris(Donovan, 1809).--Ring- Scaup.One phylogeneticinterpretation of this neckedScaup Aythyafuligula (Linnaeus, 1758).--Tufted pattern of distributions is that the group was Scaup originally limited to the Northern Hemisphere Aythya marila (Linnaeus, 1761).--Greater (perhapsthe Palearctic),with three or four sub- Scaup sequent transequatorial radiations: (1) by the Aythyaaffinis (Eyton, 1838).--LesserScaup ancestorof the Rosy-billed and Southern po- chards;(2) by the commonancestor of the Mad- agascanand Australian white-eyes (if theseare sidered directly indicative of closenessof phy- sisterspecies, but currently unresolved)or by logeneticrelationship (Sibley 1957, Johnsgard each independently; and (3) by the New Zea- 1960c).For example,Johnsgard (1960c: 30) stat- land Scaup. ed: "The high percentageof the potential hy- Revisedclassification of the Aythyini.--A phy- brids among speciesof diving ducks that are logenetic classificationfor the Aythyini is pre- actuallyrealized... forcesone to concludethat sented in Table 1, the goal of which was to 84 LIVEZE¾ [Auk,Vol. 113 incorporatemaximal phylogenetic information igan; Division of Birds,Field Museum of Natural His- while minimizing violence to existing taxo- tory, Chicago, Illinois (FMNH); Sub-departmentof nomic traditions. Inclusion of the tribe within Ornithology, British Museum of Natural History, the Anatinae is justified on the basisof syna- Tring, Hertfordshire,United Kingdom;Wildfowl and pomorphies presented by Livezey (1986). Di- WetlandsTrust, Slimbridge, Gloucester, United King- dom; Natural History Museum of Los AngelesCoun- agnosticcharacters for included taxaare shown ty, Los Angeles,California (LACM); and Division of on correspondingbranches of Figure 1, de- Ornithology,Natural History Museum,University of scribedin Appendix 1, and compiled in matrix Kansas, Lawrence, Kansas (KUMNH). P.S. Hum- form in Appendix 2. The fundamental structure phrey and two anonymousreviewers made useful of the tribe is defined by a sequenceof three commentson the manuscript. subtribes; the subtribe for Marmaronetta is new and defines the sister group of the other two LITERATURE CITED subtribes. Both of the two-species clades of ALI, S. 1960. The Pink-headed Duck Rhodonessacar- "stem" or narrow-billed pochardswere given yophylacea(Latham). Wildfowl 11:55-60. generic rank, basedon the phylogeneticrela- AM^T, J. A. 1986. A possiblesignificance of the oc- tionships inferred here and seniority of corre- curenceof chin-spotsin male ducks.Gerfaut 76: spondingtaxa. The well supportedmonophyly 31-35. of the "true" or broad-billed pochards,and the AMAT,J.A. 1991. Effectsof Red-crestedPochard nest resolved relationships of the three included parasitismon Mallards. Wilson Bull. 103:501-503. subgroups(redheads, white-eyes, and scaups; AMERICAN ORNITHOLOGISTS' UNION. 1983. Check-list the latter including Aythya collaris),permit a of North American birds, 6th ed. Am. Ornithol. largely dichotomousdefinition of genera and Union, Washington, D.C. subgeneratraditionally included in Aythya.This ANDERSSON,M. 1984. Brood parasitismwithin spe- revision subdivides three nested subgenera cies. Pages 195-228 in Producersand scroungers (C. J. Barnard, Ed.). Croon Helm, London. within Aythyafor the redheads,white-eyes, and BARTONEK,J. C., AND J. S. HICKEY. 1969. Food habits scaups. An alternative, strictly dichotomous of Canvasbacks,Redheads, and LesserScaup in classification would entail the elevation of Ar- Manitoba. Condor 71:280-290. istonettato generic rank for the redheads,re- B^IJMEL,J. J., ^ND L. M. WITMER. 1993. Osteologia. servingthe genusAythya for the white-eyesand Pages 45-132 in Handbook of avian anatomy: scaups;this somewhatmore informative scheme Nomina anatomica avium, 2nd. ed. (J. J. Baumel, is not advocated for reasons of taxonomic sta- A. S. King, J. E. Breazile, H. E. Evans, and J. C. bility. Thesethree groupsand speciesincluded Vanden Berge,Eds.). Nuttall Ornithological Club, within each are listed in order of increasing Cambridge, Massachusetts. relationship, except as limited by incomplete BEER,J. V. 1968. The tracheaeof hybrid Anatidae. Bull. Br. Ornithol. Club 88:4-15. resolution within the white-eyes. Where indi- BELLROSE,F. C. 1976. Ducks, geese and swans of cated, common names of specieswere altered North America. Stackpole Books, Harrisburg, to describemore accuratelytribal, generic,and Pennsylvania. subgenericmembership. BOETTICHER,H., VON. 1942. •Iber die Einteilung der Familie der Entenv6gel (Anatidae) in Unterfam- ACKNOWLEDGMENTS ilien und Sektionen. Zool. Anz. 140:37-48. BOETTICHER,H., VON. 1952. G•inse-und Entenv6gel This researchwas supportedby National Science ausaller Welt. Geest& Portig K.-G., Leipzig, Ger- Foundationgrants BSR-8515523 and BSR-9129545,and many. BSR-9396249,and by grants from the National Mu- BREMER,K. 1988. The limits of amino acid sequence seumof Natural History and the AmericanMuseum datain angiospermphylogenetic reconstruction. of Natural History.G. Mack and R. L. Zusi generously Evolution 42:795-803. hosted me on several prolonged visits. In addition to BRODKORB,P. 1964. Catalogueof fossil birds: Part 2 specimensin the collectionof the Carnegie Museum (Anseriformes through Galliformes). Bull. Flor- of Natural History, I examined specimensborrowed ida State Mus. (Biol. Sci.) 8:195-335. or studied in the following institutions:Division of BROMAN,][. 1942. •ber die Embryonalentwicklung Birds, National Museum of Natural History, Wash- der Enten-Syrinx.Anat. Anz. 93:241-251. ington, D.C. (USNM); Department of Ornithology, BROWN, L. H., E. K. URBAN, AND K. NEWMAN. 1982. American Museum of Natural History, New York, The birds of Africa, vol. 1. Academic Press, Lon- New York (AMNH); Division of Birds, Museum of don. Zoology, University of Michigan, Ann Arbor, Mich- BRUSH,A. H. 1976. Waterfowl feather proteins: January1996] Phylogenyof Pochards 85

Analysisof usein taxonomicstudies. J. Zool. Lond. craft, Eds.). Oxford Univ. Press, Oxford, United 179:467-498. Kingdom. BUCKNILL,J.A. 1924. The disappearanceof the Pink- HOERSCHELMANN,H. 1971. Proportionsvergleicham headedDuck (Rhodonessa caryophyllacea Lath.). Ibis Skelett von Anatiden. Zool. Anz. 186:163-188. 66:146-151. HOLLISTER,N. 1919. The systematicposition of the COLLAR,N. J., M. J. CRISI•Y,AND A. J. STATTERSFIELD. Ring-necked Duck. Auk 36:460-463. 1994. Birds to watch 2. Birdlife Conserv. Set. 4. HOWARD,H. 1964. FossilAnseriformes. Pages 233- Birdlife International,Cambridge, United King- 326 in The waterfowl of the world, vol. 4 (J. De- dom. lacour,Ed.). Country Life, London. COTTAM, C. 1939. Food habits of North American DELHOYO, J., A. ELLIOTT,AND J. SARGATAL(Eds.). 1992. diving ducks. U.S. Dep. Agr. Tech. Bull. 643. Handbook of the birds of the world, vol. 1. Lynx CRAMP, S., AND K. E. L. SIMMONS. 1977. Handbook Editions, Barcelona. of the birds of Europe and the Middle East and HUMPHREY,P.S., AND G. A. CLARK,JR. 1964. The North Africa, vol. 1. Oxford Univ. Press, Oxford, anatomyof waterfowl. Pages167-232 in The wa- United Kingdom. terfowl of the world, vol. 4 (J. Delacour, Ed.). DELACOUR,J. 1956. The waterfowl of the world, vol. Country Life, London. 2. Country Life, London. HUMPHREY,P.S., AND S. D. RIPLEY. 1962. The affin- DELACOUR,J. 1959. The waterfowl of the world, vol. ities of the Pink-headedDuck (Rhodonessacary- 3. Country Life, London. ophyllacea).Postilia 61:1-21. DELACOUR,J. 1964. Correctionsand additions.Pages JACOB,J., AND H. HOERSCHELMANN.1993. Ein Beitrag 327-354 in The waterfowl of the world, vol. 4 (J. zur Chemotaxonomieder Entenv•Sgel(Aves: An- Delacour, Ed.). Country Life, London. seriformes).Mitt. Hamburg Zool. Mus. Inst. 90: DELACOUR,J., AND E. MAYR. 1945. The family Anat- 379-400. idae. Wilson Bull. 57:3-55. JOHNSGARD,P. A. 1960a. Comparative behavior of DELACOUR,J., AND E. MAYR. 1946. Supplementary the Anatidae and its evolutionary implications. notes on the family Anatidae. Wilson Bull. 58: Wildfowl 11:31-45. 104-110. JOHNSGARD,P.A. 1960b. Pair formation mechanisms DUNNING, J. B., JR.,ED. 1993. CRC handbook ofavian in Ands(Anatidae) and related genera.Ibis 102: body masses.CRC Press,Boca Raton, Florida. 616-618. DzuI•IN,A. 1959. Growthand plumagedevelopment JOHNSGARD,P.A. 1960c. Hybridization in the Anat- of wild-trapped juvenile Canvasback(Aythya val- idae and its taxonomicimplications. Condor 62: isineria).J. Wildl. Manage.23:279-290. 25-33. EADIE,J. McA., F. P. KEHOE,AND T. D. NUDDS. 1988. [OHNSGARD,P.A. 1961a. The taxonomyof the Anat- Pre-hatchand post-hatchbrood amalgamationin idae--A behaviouralanalysis. Ibis 103:71-85. North American Anatidae: A review of hypoth- JOHNSGARD,P.A. 1961b. The systematicposition of eses.Can. J. Zool. 66:1709-1721. the Marbled Teal. Bull. Br. Ornithol. Club 81:37- EYrON,T.C. 1838. A mongraph on the Anatidae, or 43. duck tribe, including the geeseand swans.Long- JOHNSGARD,P. A. 1961c. Tracheal anatomy of the mans, London. Anatidae and its taxonomicsignificance. Wild- FAITH,D. P. 1989. Homoplasyas pattern: Multivar- fowl 12:58-69. iate analysisof morphologicalconvergence in JOHNSGARD,P. A. 1962. Evolutionary trends in the anseriforms. Cladistics 5:235-258. behaviour and morphology of the Anatidae. FELSENSTEIN,J. 1985. Confidencelimits on phylog- Wildfowl 13:130-148. enies:An approachusing the bootstrap.Evolu- JOHNSGARD,P.A. 1963. Behavioralisolating mech- tion 39:783-791. anismsin the family Anatidae. Pages531-543 in GARROD,A.H. 1875. On the form of the lower larynx ProceedingsXIII International Ornithological in certain speciesof ducks.Proc. Zool. Soc.Lond. Congress(C. G. Sibley, Ed.). Ithaca, New York, 1875:279-284. 1962.American Ornithologists' Union, Washing- GILLHAM, E., J. M. HARRISON,AND J. G. HARRISON. ton, D.C. 1966. A study of certain Aythya hybrids.Wild- JOHNSGARD,P.A. 1965. Handbook of waterfowl be- fowl 17:49-65. havior. London, Constable. GREEN,A. J. (ED.). 1993. The statusand conservation JOHNSGARD,P. A. 1968. Waterfowl:Their biology of the Marbled Teal Marmaronettaangustirostris. and natural history. Univ. NebraskaPress, Lin- Internat. Waterfowl and WetlandsRes. Bur. Spec. coln. Publ. No. 23. JOHNSGARD,P.A. 1978. Ducks,geese, and swansof HILLIS, D. M. 1991. Discriminating between phy- the world. Lincoln, Univ. Nebraska Press. logenetic signal and random noise in DNA se- JOHNSGARD,P.A. 1979. Order Anseriformes.Pages quences.Pages 278-294 in Phylogeneticanalysis 425-506 in Checklist of birds of the world, vol. of DNA sequences(M. M. Miyamotoand J. Cra- 1, 2nd. ed. (E. Mayr and C. W. Cottrell, Eds.). 86 LIVEZIEY [Auk, Vol. 113

Museum of Comparative Zoology, Cambridge, whistling and White-backed ducks (Anatidae: Massachusetts. Dendrocygninae)using morphologicalcharac- KAGIELM^NN,G. 1951. Studien fiber Farbfelderung, ters. Ann. Carnegie Mus. 64:65-97. Zeichnung und Firbung der Wild-und Hausen- LIVEZIEY,B.C. 1995c. Phylogeny and comparative ten. Zool. Jahrb. 62:513-630. ecologyof stiff-tailedducks (Anatidae: Oxyurini). K•LLERSJ•,M., J. S. FARRIS,A. G. KLUGE,AND C. BOLT. Wilson Bull. 107:214-234. 1992. Skewness and permutation. Cladistics LIvEZEY,B.C. 1996. A phylogeneticreassessment of 8:275-287. the tadornine-anatinedivergence (Aves: Anser- K•,J. 1970. Theadaptiveradiationofparentalcare iformes:Anatidae). Ann. Carnegie Mus. 65: in in waterfowl. Pages357-392 in Socialbehaviour press. in birds and mammals (J. H. Crook, Ed.). Aca- LIvEZIE¾,B.C., AND L. D. MAR?IN. 1988. The system- demic Press, New York. atic position of the Miocene anatid Anas[?]blan- KEHOE,F. P., AND C. D. ANr,NEY. 1985. Variation in chardi Milne-Edwards. J. Vert. Paleontol. 8:196- digestiveorgan size among five speciesof diving 211. ducks (Aythyaspp.). Can. J. Zool. 63:2339-2342. MADDISON, W. P., mad D. R. MADDISON. 1992. KIEHOIE,F. P., ANDV. G. THOMAS.1987. A comparison MacClade, version 3. Sinauer Associates, Sun- of interspecificdifferences in the morphologyof derland, Massachusetts. external and internal feeding apparatusamong MADGE, S., AND H. BURN. 1988. Waterfowl: An iden- North American Anatidae. Can. J. Zool. 65:1818- tificationguide to the ducks,geese and swansof 1822. the world. Boston,Houghton Mifflin. KESSLER,L. G., ANDJ. C. AVISE. 1984. Systematicre- MADSEN, C. S., K. P. MCHUGH, • S. R. DIE KLOFr. lationshipsamong waterfowl (Anatidae) inferred 1988. A partialclassification of waterfowl(Anat- from restrictionendonuclease analysis of mito- idae) basedon single-copyDNA. Auk 105:452- chondrial DNA. Syst.Zool. 33:370-380. 459. KESSLER,L. G., AND J. C. AVISE. 1985. A comparative MARCHANT,S., AND P. J. HIGGINS (COORDINATORS). descriptionof mitochondrial DNA differentia- 1990. Handbook of Australian, New Zealand and tion in selectedavian and other vertebrate gen- Antarcticbirds, vol. 1, part B. Oxford Univ. Press, era. Mol. Biol. Evol. 2:109-125. Melbourne. KING,A.S. 1989. Functionalanatomy of the syrinx. McKINNEY,F. 1978. Comparativeapproaches to so- Pages105-192 in Formand functionin birds,vol. cial behaviorin closelyrelated species of birds. 4 (A. S. King and J. McLelland, Eds.).Academic Pages1-38 in Advancesin the studyof behavior, Press, London. vol. 8 (J. S. Rosenblatt,R. A. Hinde, C. Beer and KING,A. S. 1993. Apparatusrespiratorius [systema M.-C. Busnel, Eds.). Academic Press, New York. respiratorium].Pages 257-299 in Handbook of McLIELt,m'xrD, J. 1989. Larynx and trachea.Pages 69- avian anatomy: Nomina anatomica avium, 2nd 103 in Form and function in birds, vol. 4 (A. S. ed. (J. J. Baumel,A. S. King, J. E. Breazile, H. E. King and J. McLelland, Eds.). Academic Press, Evans,and J.C. Vanden Berge,Eds.). Cambridge, London. Massachusetts, Nuttall Ornithol. Club. McNIEIL, R., P. DR•PEAU, • J. D. GOSs-CuST•RD. LAGERQUIST,B. A., • C. D. ANr, NEY. 1989. Inter- 1992. The occurrenceand adaptive significance specificdifferences in bill and tongue morphol- of nocturnal habits in waterfowl. Biol. Rev. 67: ogy among diving ducks (Aythya spp., Oxyura 381-419. jamaicensis).Can. J. Zool. 67:2694-2699. MENDALL,H. L. 1958. The Ring-neckedDuck in the LATHAM,J. 1798. An essayon the trachea•or wind- Northeast. Univ. Maine Bull. 55:1-317. pipes of variouskinds of birds. Trans. Linnean MILSTEIN,P. LIES. 1979. The evolutionary signifi- Soc. (Lond.) 4:93-128. canceof wild hybridization in South African LIVEZEY,B.C. 1986. A phylogeneticanalysis of Re- highveld ducks.Ostrich (Suppl.) 13:1-48. cent anseriform genera using morphological MOLLENHOI•I•,K. 1885. Die Gr/Ssseder Flugfl•ichen. characters. Auk 103:737-754. Pfluger'sArch. Physiol.35:407-453. LIVEZEY,B.C. 1989. Phylogeneticrelationships and NIELSON,C. J. 1993. The downywaterfowl of North incipient flightlessnessof the extinct Auckland America. Delta Station Press, Deerfield, Illinois. Islands Merganser.Wilson Bull. 101:410-435. NUMACHI, K., M. WATADA, R. K•KIZ•WA, N. KURODA, LIVEZEY,B.C. 1991. A phylogenetic analysis and ANDS. UTIDA. 1983. Evolutionarygenetics of classificationof Recent dabbling ducks (Tribe the Anatidae. Tori 32:63-74. Anatini) basedon comparativemorphology. Auk OlviLAND,K.E. 1994. Charactercongruence between 108:471-507. a molecularand a morphologicalphylogeny for LIVEZEY,B.C. 1995a. Phylogeny and evolutionary dabbling ducks(Anas). Syst. Biol. 43:369-386. ecologyof modernseaducks (Anatidae: Mergini). PALMER,R. S. 1976. Handbook of North American Condor 97:233-255. birds, vol. 3. Yale Univ. Press, New Haven, Con- LIVEZEY,B.C. 1995b. A phylogeneticanalysis of the necticut. January1996] Phylogenyof Pochards 87

PATTON,J. C., ANDJ. C. AVlSE. 1985. Evolutionary TOME, M. W., AND D. A. WRUBLESKI. 1988. Under- geneticsof birds IV: Ratesof protein divergence water foraging behavior of Canvasbacks,Lesser in waterfowl (Anatidae). Genetica 68:129-143. Scaups,and Ruddy Ducks. Condor 90:168-172. PETERS,J.L. 1931. Check-list of birds of the world, TOWNSEND,C.W. 1930. Diving habits in the genus vol. 1. Harvard University Press,Cambridge, Nyroca.Auk 47:554. Massachusetts. TUCKER, G. M., ^NIV M. F. HF•TH. 1994. Birds in PHILLIPS,J. C. 1922. A natural historyof the ducks, Europe: Their . Birdlife Con- vol. 1. Houghton Mifflin, Boston. serv. Set. 3. Birdlife International, Cambridge, PHILLIPS,J. C. 1925. A natural history of the ducks, United Kingdom. vol. 3. Houghton Mifflin, Boston. VERHEYEN,R. 1953. Bijdragetot de osteologieen de POOLE,E.L. 1938. Weights and wing areasin North systematiek der Anseriformes. Gerfaut 43:373- American birds. Auk 55:511-517. 456. PRESTWICH,A.A. 1974. The Pink-headed Duck (Rho- W^RNER, R.W. 1971. The structural basis of the or- donessacaryophyllacea) in the wild and in captiv- gan of voicein the generaAnas and Aythya(Aves). ity. Avic. Mag. 80:47-52. J. Zool. Lond. 164:197-207. RAIKOw, R. J. 1970. The function and evolution of WELLER,M. W. 1957. Growth, weights, and plum- the supraorbitalprocess in ducks.Auk 87:568- ages of the Redhead, Aythya americana.Wilson 572. Bull. 69:4-38. RAIKOW,R.J. 1973. Locomotor mechanisms in North WELLER,M.W. 1959. Parasiticegg laying in the Red- American ducks. Wilson Bull. 85:295-307. head (Aythya americana)and other North Amer- ROHwER,F. C. 1988. Inter- and intraspecificrela- ican Anatidae. Ecol. Monogr. 29:333-365. tionships between egg size and clutch size in WELLER,M. W. 1964a. Distribution and speciesre- waterfowl. Auk 105:161-176. lationships. Pages 108-120 in The waterfowl of ROHWER, F. C., AND S. FREEMAN. 1989. The distri- the world, vol. 4 (J. Delacour,Ed.). Country Life, butionof conspecificnest parasitism in birds.Can. London. J. Zool. 67:239-253. WELLER,M.W. 1964b. Ecology.Pages 80-107 in The S^LV^IVORI,T. 1895. Catalogueof the Chenomor- waterfowl of the world, vol. 4 (J. Delacour, Ed.). phae (Palamedeae,Phoenicopteri, Anseres), Country Life, London. Crypturi and Ratitae in the collection of the Brit- WELLER,M. W. 1964c. General habits. Pages 15-34 ish Museum.Longmans, London. in The waterfowl of the world, vol. 4 (J. Delacour, SANIVERSON,M.J. 1989. Confidencelimits on phy- Ed.). Country Life, London. logenies:The bootstrap revisited. Cladistics 5:113- WELLER,M.W. 1964d. The reproductivecycle. Pages 129. 35-79 in The waterfowl of the world, vol. 4 (J. SCHERER,S.,AND T. HILSBERG.1982. Hybridisierung Delacour,Ed.). Country Life, London. und Verwandtschaftsgradeinnerhalb der Anat- WILEY,E. O. 1981. Phylogenetics:The theory and idae--eine systematischeund evolutionstheore- practiceof phylogeneticsystematics. J. Wiley & tischeBetrachtung. J. Ornithol. 123:357-380. Sons, New York. SCHIOLER,E.L. 1926. DanmarksFugle, vol 2. Nor- WILMf•,L. 1993. A recent record of the Madagascar disk Forlag,Kobenhavn. PochardAythya innotataon Lake Alaotra, Mada- SCHtSNWETTER,M. 1961. Handbuch der Oologie, part gascar.Bull. Br. Ornithol. Club 113:188-189. 3. AkademieVerlag, Berlin. WILM•, L. 1994. Status, distribution and conserva- ScoTT, D, K., AND T, H. CLUTTON-BROCK. 1989. Mat- tion of two Madagascarbird speciesendemic to ing systems,parasites and plumagedimorphism Lake Alaotra: Delacour's Grebe Tachybaptusru- in waterfowl. Behav. Ecol. Sociobiol. 26:261-273. folavatusand MadagascarPochard Aythya inno- SIBLEY,C. G. 1957. The evolutionaryand taxonomic rata. Biol. Conserv. 69:15-21. significanceof sexual dimorphismand hybrid- WILSON, S. F., AND C. D. ANKNEY. 1988. Variation in ization in birds. Condor 59:166-191. structuralsize and wing size of Lesserand Great- SIBLEY,C. O., ANDJ. E. AHLQUIST.1990. Phylogeny er scaup.Can. J. Zool. 66:2045-2048. and classificationof birds:A study in molecular WOLTERS,H.E. 1976. Die Vogelarten der Erde, part evolution. Yale Univ. Press, New Haven, Con- 2. Paul Parey, Hamburg. necticut. WOOD, D. S., AND G. D. SCHNELL. 1986. Revised world SIBLEY,C. G., ^ND B. L. MONROE,JR. 1990. Distri- inventory of avian skeletal specimens, 1986. bution and taxonomyof birds of the world. Yale American Ornithologists' Union and Oklahoma Univ. Press, New Haven, Connecticut. BiologicalSurvey, Norman, Oklahoma. SMALLSHIRE,D. 1986. The frequencyof hybridducks WOOLFENDEN,G. E. 1961. Postcranialosteology of in the Midlands. Br. Birds 79:87-89. the waterfowl. Florida State Mus. Bull. (Biol. Sci.) SWOFFORD,D.L. 1993. PAUP:Phylogenetic analysis 6:1-129. using parsimony, version 3.1. Illinois Natural WIUGHT, R.G. 1925. The ducks of India: Their habits, History Survey,Champaign. breeding groundsand migrations;together with 88 LIVEZE¾ [Auk,Vol. 113

other useful information for the sportsmanand lamina covering dorsal (of two) canaliculi (character observer.H. F. & G. Witherby, London. 69):(a) present;(b) largelyor completelylacking. 14. YOUNG, H. G., •qv J. G. SMITH. 1989. The search for tarsometatarsus,corpus tarsometatarsi, relative dor- the MadagascarPochard Aythya innotata: Survey sal prominence of faciessubcutanea medialis and fa- of Lac Alaotra, MadagascarOctober-November, cies subcutanealateralis (character75): (a) equal, no 1989. Dodo 26:17-34. torsionof corpusevident; (b) medialisless prominent than lateralis,related to significanttorsion of corpus APPENDIX1.--Character descriptions. Primitive about long axis. statescorrespond to state"a" unlessanother stateis Trachea.--Pertainto males(see Fig. 5). CI was 1.0 highlighted in boldface.CI = consistencyindex. for all but character 2, which was 0.50. 1. Syrinx, bulla syringealis(primary chamber):(a) Skeleton.--Indexnumbers of osteologicalcharacters solid;(b) with fenestrae.2. Syrinx,bulla syringealis derived from thosegiven by Livezey(1986) are given (primary chamber):(a) rounded;(b) flattened"whorl". in parenthesesafter charactername; most were re- 3. Bulbustrachealis, single, gradually dialated: (a) ab- corded to restrict the states to those found in the sent(includes modal reversals in fuligula,collaris, af- Aythyini, those describedas "revised" indicate new finis, and marila);(b) variably evident (includesan- character definitions, and those in which corrections gustirostris;unique shapesin peposaca,rufina coded in codingsbased on the wider, species-levelcompar- separately,below). 4. Syrinx, bulla syringealis,solid, isons made here are so indicated. CI was 1.00 for all bulbous,basal chamber: (a) absent;(b) present.5. Syr- but characters 10 and 14, which were 0.50. inx, tympanum: (a) not enlarged; (b) enlarged, sub- 1. Columna vertebralis, vertebrae cervicales, modal equal to bulla syringealisin volume (includesinter- number (character21): (a) 16; (b) 17.2. Sternum, ros- mediatestate in fuligula).6. Bulbustrachealis (if pres- trum sterni, spina externa (character79, revised):(a) ent), constriction in middle, forming two bulbiculi long, peglike;(b) obsolete;(c) short,squarish; (d) me- tracheales:(a) absent;(b) present.7. Bulbustrachealis dially separated,sharp, pair of points. 3. Sternum, (if present),shape abrupt, cylindrical: (a) absent;(b) rostrum sterni, labrum interna (character 82): (a) a present. rounded notch; (b) rounded notch with small medial Natal integument.--Pertainto fresh,class-la downy point. 4. Humerus, extremitasproximaIls humeri, fos- young (seeFig. 6). CI was 1.0 for all but characters3 sa pneumotricipitalis,foramen pneumaticum(char- (CI = 0.50) and 5 (CI = 0.33). acter 28): (a) present;(b) absent.5. Humerus, extrem- 1. Pale scapularand rump spots:(a) present;(b) itasdistalis, relative caudal prominence of epicondyla obsolete.2. Darkpostorbital stripe (variable): (a) pres- dorsalisand ventralis(character 33, revised):(a) ep- ent; (b) reducedor obsolete.3. Groundcolor of plum- icondyla essentiallyequal; (b) epicondylusdorsalis age:(a) whitish;(b) yellowish.4. Pale alar stripe:(a) cranialto epicondylusventralis. 6. Carpometacarpus, present; (b) obsolete.5. Crural region: (a) pale, like extremitasproximalis carpometacarpi,trochlea car- adjacentregions of venter; (b) contrastingly,exten- palis,labrum dorsalis, rounded prominence on distal sively dusky (novaeseelandiaevariable). 6. Distinct terminus (character37; correctedwith respectto la- duskybreast band: (a) absent;(b) present.7. Cheeks: brum involved):(a) present;(b) absent.7. Carpome- (a) pale; (b) variablydarkened, typically by irregular tacarpus,corpus carpometacarpi, os metacarpalema- stripe(s).8. Dark preorbital stripe (problematic):(a) jus, faciesdorsalis, impressio m. extensormetacarpi present(outgroups); (b) obsoleteor absent(includes ulnaris, positionrelative to synostosismetacarpalis fuligula,marila, and affinis,in which face darkened). proximaIls(character 43): (a) completelyproximal; (b) 9. Dark, contrastingauricular spot: (a) present;(b) opposite,at leastin part.8. Carpometacarpus,extrem- absent. itas proximaliscarpometacarpi, trochlea carpalis, la- Definitiveintegument.--Pertain to definitive alter- brum ventralis,orientation relative to corpuscarpo- nate plumagesof malesunless indicated otherwise. metacarpi,facies ventralis (character 48): (a) coplanar; 1. Breast:(a) not distinguished;(b) black with iri- (b) laterally rotated.9. Femur,corpus femoris, cran- descence,comparatively sharp (including caryophyl- iocaudalcurvature in lateralperspective (character 55, laceawith dark brown, no break); (c) brown with ir- revised): absent;(b) present. 10. Femur, extremitas idescence,comparatively sharp. CI = 1.00. 2. Head, distalis,fossa poplitea (character 56, revised):(a) shal- contrastingchestnut coloration: (a) absent;(b) pres- low; (b) deep. 11. Tibiotarsus,extremitas distalis tib- ent. CI = 1.00. 3. Head, contrastingpinkish-red col- iotarsi, condyla medialis et lateralis, relative cranial oration:(a) absent;(b) present(comparatively pink in prominence(character 64): (a) condylusmedialis dis- caryophyllacea).CI = 1.00. 4. Head, contrastingirides- tinctly greater than condyluslateralis; (b) condyla cent blackcoloration: (a) absent;(b) present.CI = 0.50. equallyprominent. 12. Tibiotarsus,extremitas prox- 5. Head, contrastingdull (chocolate)brown with iri- imalistibiotarsi, crista cnemialis cranialis, distinct ridge descence:(a) absent;(b) present.CI = 1.00.6. Under- continuing distally along corpus tibiotarsi, facies tail coverts,contrasting black color: (a) absent;(b) cranialis,margo cranialis (character 65): (a) absent;(b) present,but centerregion white; (c) present,includ- present. 13. Tarsometatarsus, extremitas distalis tar- ing entireventer. CI = 0.67.7.Undertail coverts, sharp sometatarsi, canalis interosseus tendineus, osseus white colorwith blackborder: (a) absent;(b) present. January1996] PhylogenyofPochards 89

A C

I

E

Fig,5. Bullaeossea syringeales of selectedAythyini, males, ventral views: (A) M. angustirostris(LACM 101686);(B) R. rufina(USNM 490521); (C) M, peposaca(KUMNH 81984);(D) A. americana(KUMNH 21244); (E) A, australis(KUMNH 85354);and (F) A, affinis(KUMNH 15238).

Fig.6. Diagramsof natalpatterns of selectedAythyini (age class I), lateralviews: (A) M, angustirostris (WWT712); (B) R, rufina(FMNH 351541);(C) M. peposaca(USNM 307515); (D) A. valisineria(AMNH 351049); (E) A. baeri(FMNH 12891);and (F) A. marila(AMNH 76833), 90 LIVEZEY [Auk,Vol. 113

CI = 0.50.8. Venter, essentiallydark color through- yophyllacea);(b) black. CI = 1.00. 30. Wing linings, out, producedby unevenly distributeddark brown cranial margin: (a) white; (b) dark brown or black;(c) feathers:(a) absent;(b) present. CI = 1.00. Also, see faintly mottledwith pale gray. CI = 0.67. 31. Dorsal nextcharacter. 9. Upper belly, groundcolor: (a) white; surfaceof remiges,contrastingly pale silvery gray wash (b) brown (includesunique, problematical, black-and- basally:(a) absent;(b) present.CI = 0.33. 32. Dorsal white vermiculationsof peposaca).CI = 1.00.10.Low- surfaceof remiges,contrastingly white colorbasally: er belly, distinctand contrastingbrownish suffusion (a) absent;(b) present(varying to salmoncolor in (especiallyon crural region):(a) absent;(b) present. caryophyllacea).CI = 0.33.33. Dorsal surface of fore- CI = 1.00. 11. Dorsum, yoke of iridescent blackish wing (coverts),white border along leading (cranial) from nape to upper back along midline: (a) absent; edge: (a) absent; (b) present. CI = 0.50. 34. Dorsal (b) present (variable in baeri).CI = 1.00.12. Axillaries surfaceof forewing (coverts),ground color: (a) pale (adults of both sexes):(a) white; (b) brown. CI = 1.00. grayish brown; (b) green-iridescentblack (vestigial 13. Hallux, cutaneouslobation: (a) absent;(b) present iridescenceand paler in insular australis[subspecies (smallin caryophyllacea).CI = 1.00.14.Chin and throat extima]).CI = 0.50.35.Rectrices: (a) approximatelythe (female):(a) pale color conspicuous,extending well colorof othercontour feathers; (b) contrastinglypale, down throat;(b) palecolor inconspicuous, only mod- whitish. CI = 1.00. 36. Deftrum: (a) dark, if rest of eratelyextensive; (c) pale color (if any), distinctbut maxillapale, sharplycontrasting; (b) pale, like restof confinedposteriorly to chin areaby dark region.CI maxilla.CI = 1.00.37. Face,color largelypale brown, = 1.00.15.Feathers at baseof bill, contrastinglywhite, with only dark confined to crown stripe (female): (a) lateralpatches, confined to smallregion dorsal to gape absent;(b) present(uniquely toned in caryophyllacea). (female):(a) absent(includes more conspicuous, com- CI = 1.00.38. Dusky dorsal neck stripe (female): (a) plex patterns of some Netta); (b) present (includes absent; (b) present. CI = 0.50. 39. Sides and flanks, comparativelycrescent-shaped state of collaris;vari- uniform dark, ventrally extensive,typically contin- able in novaeseelandiae).CI = 1.00.16. Facialpattern, uous with dark venter: (a) absent; (b) present (com- stronglydemarcated by caudoventrallysloping white paratively restrictedwith jagged ventral margin in areasat bill basebroadly confluent with white throat rufina).CI = 0.50.40.Sides and flanks, uniformly dark and somewhatventrally curved, typically whitish brown, ventrally restrictedband of uniform width: postorbital stripe (definitive female): (a) absent; (b) (a) absent;(b) present,brown; (c) present, chestnut. present(comparatively less distinct in caryophyllacea). CI = 0.50.41. Sidesand flanks, uniformly white: (a) CI = 1.00.17. Bill, ephemeral,variably conspicuous, absent; (b) present. CI = 1.00. 42. Sides and flanks, pale subterminalband (especiallymales): (a) absent white with grayish vermiculations: (a) absent; (b) (includessuggestion in angustirostris);(b) present (most present. CI = 1.00.43. Sides and flanks, white with marked in americana,australis, and collaris).CI = 0.50. fine black barring: (a) absent;(b) present.CI = 1.00. 18. Bill, ground color: (a) dark; (b) bright red (com- 44. Metallic-coloredspeculum: (a) present;(b) absent. paratively pink in caryophyllacea).CI = 0.50.19. Foot, CI = 1.00. 45. Blackish eye patches:(a) absent; (b) color (adults,both sexes):(a) greenishor yellowish; present. CI = 1.00.46. Bright pink head coloration: (b) orangeor reddish;(c) gray.CI = 0.67.20. Mantle, (a) absent;(b) present.CI = 1.00.47.Rounded, bushy scapulars,and typically tertials, white ground color crest:(a) absent;(b) present.CI = 1.00.48. Ventrally with fine, wavy, transverseblack bars: (a) absent;(b) extensivewhite flank patches:(a) absent;(b) present. present.CI = 1.00.21.Mantle, scapulars,and typically CI = 1.00.49. Maxilla, bright red basal swelling: (a) tertials, black ground color with fine, wavy, trans- absent;(b) present.CI = 1.00.50. Dark blackishcrown, versewhite bars:(a) absent;(b) present.CI = 1.00.22. nape, menturn:(a) absent;(b) present. CI = 1.00.51. Mantle, scapulars,and typicallytertials, black ground Chestnutbreast: (a) absent;(b) present.CI = 1.00.52. colorwith greenishiridescence and fine white speck- Long, slender crown tuff: (a) absent;(b) present. CI ling: (a) absent;(b) present. CI = 0.33. 23. Mantle, = 1.00.53.Black breast (if present)continued caudally scapulars,and typically tertials,brown ground color by ventromedialband to undertailcoverts: (a) absent; with palebuff scallopingproduced by rhomboid,ter- (b) present.CI = 1.00.54.Uniformly black body plum- minal, white spotson feathers:(a) absent;(b) present. age: (a) absent; (b) present. CI = 1.00. 55. Short, re- CI = 1.00. 24, Iris, color: (a) dark brown; (b) red stricted,rounded occipital crest:(a) absent;(b) pres- (brighterin adults,males); (c) orange;(d) yellow. CI ent. CI = 1.00.56. Upper wing coverts,cranial margin = 1.00.25. Iridescenceof crown:(a) absent;(b) pres- at bend of wing, narrow white patch: (a) absent;(b) ent, green; (c) present, purple. CI = 0.40.26. Irides- present. CI = 1.00.57. White, vertical pectoral stripe, cenceof auricularregion: (a) absent;(b) present,green; caudalto black breast:(a) absent;(b) present. CI = (c) present,purple. CI = 0.40.27. Rump,and usually 1.00.58.Fine, white, ventrally curvedpostorbital stripe also undertail coverts,contrasting blackish color: (a) (females):(a) absent;(b) present.CI = 1.00. 59. Nar- absent;(b) present (vestigial to obsoletein australis). row, dark dorsalstripe from baseof neck to nape:(a) CI = 1.00.28. Modal number of pairs of rectrices:(a) absent;(b) present.CI = 1.00.60.Proximal secondary seven;(b) eight. CI = 1.00.29. Wing linings, ground remiges,fine black external margin: (a) absent;(b) color:(a) essentiallywhite (with pinkish washin car- present. CI = 1.00. 61. Secondaryremiges, dark January1996] PhylogenyofPochards 91

(sub)terminalband: (a) absent;(b) present.CI = 0.50. and-white vermiculations:(a) absent;(b) present.CI 62. Dorsumand sides,fine white speckling(females): = 1.00.69. Chestnutcollar contrastingwith metallic (a) absent;(b) present.CI = 1.00.63. Venter,lower blackof headand neck:(a) absent;(b) present.CI = belly, duskywash contrasting with white cranially: 1.00. (a) absent;(b) present.CI = 1.00. 64. Proximal sec- Ecomorphologicalattributes.--Where logical ordina- ondaryremiges, narrow, white terminalbars: (a) pres- tion of stateswithin multistatecharacter was evident, ent; (b) absent. CI = 0.33. 65. Maxilla, narrow black attribute was treated as ordered. line at base:(a) absent;(b) present.CI = 1.00.66.Neck, A. Mean bodymass (g; ordered):(a) < 700;(b) 700- ventral surface,dark brown stripe from menturnto 1,000;(c) > 1,000.B. Mean clutchsize: (a) 6-8;(b) 9-11. breast:(a) absent;(b) present. CI = 1.00.67. Crown, C. Nest site: (a) upland; (b) emergent aquatic vege- specklingwith brown and white: (a) absent;(b) pres- tation; (a/b) variable. D. Activity pattern (ordered): ent. CI = 1.00.68.Proximal secondary remiges, black- (a) diurnal;(b) crepuscular;(c) nocturnal.

APPENDIX2. Matrix of 99 morphologicalcharacters used in phylogeneticanalysis of Aythyini and hypo- theticalancestor, followed by four attributesmapped a posteriori(lettered A-D). Skeletalcharacters labelled "sl" to "s14," trachealcharacters "tl" to "t7," natal characters"nl" to "n9," and those of definitive integ- ument "dl" to "d69." Statescoded as lowercaseletters, and questionmarks signify undeterminedstates.

Character

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Taxon sl s2 s3 s4 s5 s6 s7 s8 s9 s10slls12s13s14 tl t2 t3 t4 t5 t6 t7 nl n2

1Ancestor a a a a a a a a a a a a a a a a a a a a a a a 2 angustirostr• a a a a a a a b a a a a a a a a a a a a a a a 3 caryophyllacea b b b a b b b b a a a a b a b a b b a a a ? ? 4 r•na b b b a b b b b a b a a b b b b b b b b a a b 5 peposaca b c b a b b b b a a a a b b b b b b a a b a b 6 erythrophthalma b d b a b b b b a a a a b b b b b b b a a a b 7•rina b d b b b b b b b b b b b b b b b b a a a a b 8 amer&ana b d b b b b b b b b b b b b b b b b a a a a b 9 val•iner• b d b b b b b b b b b b b b b b b b a a a a b 10 austral• b d b b b b b b b b b b b b b b b b a a a a b 11 nyroca b d b b b b b b b b b b b b b b b b a a a a b 12 innotata b d b b b b b b b b b b b b b b b b a a a a b 13 baeri b d b b b b b b b b b b b b b b b b a a a a b 14 novaeseelandiae b d b b b b b b b b b b b b b b b b a a a a b 15 collar• b d b b b b b b b b b b b b b b a b a a a a b 16•l•ula b d b b b b b b b b b b b b b b a b b a a b b 17 marila b d b b b b b b b b b b b b b b a b b a a b b 18 •n• b d b b b b b b b b b b b b b b a b b a a b b

Character

24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Taxon n3 n4 n5 n6 n7 n8 n9 dl d2 d3 d4 d5 d6 d7 d8 d9 d10 dll d12 d13 d14 d15

1Ancestor a a a a a a a a a a a a a a a a a a a a a a 2 angustirostr• a a a a a b b a a a a a a a a a a a a a a a 3 caryophyllacea ? ? ? ? ? ? ? b a b a a c a a b a a a b a a 4 r•na b a a a a b b b a b a a c a a b a a a b a a 5 p•osaca b a a a a b b b a a b a b b a b a a a b a a 6 erythrophthalma b a a a a b b b a a b a c a a b a a b b a a 7•rina b a a a a b b b b a a a c a a a a a a b b a 8 americana b a a a a b b b b a a a c a a a a a a b b a 9 val•ineria b a a a a b b b b a a a c a a a a a a b b a 10 austral• b a a a a b b c a a a b a b a a b a a b c a 11 nyroca b a b a a b b c a a a b a b a a b b a b c a 12 innotata b a b a a b b c a a a b a b a a b a a b c a 13 baeri b a b a a b b c a a a b a b a a b b a b c a 14 novaeseelandiae b a b a a b b b a a b a c a b a a a a b c b 15 collar• b a a a a b b b a a b a c a a a a a a b c b 16•l•ula b b b b b b b b a a b a c a a a a a a b c b 17 mar•a a b b b b b b b a a b a c a a a a a a b c b 18 •n• a b b b b b b b a a b a c a a a a a a b c b 92 Ln'EZE¾ [Auk, Vol. 113

APPENDIX 2. Continued.

Character

46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 Taxon d16 d17 d18 d19 d20 d21 d22 d23 d24 d25 d26 d27 d28 d29 d30 d31 d32 d33 d34 d35

1 Ancestor a a a a a a a a a a a a a a a a a a a a 2 angusiirosiris a a a a a a a b a a a a a a a b a a a a 3 caryophyllacea b a b b a a a a b a a b b a a a b b a b 4 rufina b a b b a a a a b a a b b a a a b b a b 5 peposaca b a b b a a a a b b c b b a b a b b b a 6 erythrophthalma b a a c a a a a b b c b b b b a b a b a 7 ferina a b a c b a a a c a a b a a c b a a a a 8 americana a b a c b a a a c a a b a a c b a a a a 9 valisineria a a a c b a a a c a a b a a c b a a a a 10 australis a b a c a a a a d b a b a a b a b a b a 11 nyroca a b a c a a b a d a a b a a b a b a b a 12 innotata a b a c a a a a d b a b a a b a b a b a 13 baeri a b a c a a b a d a b b a a b a b a b a 14 novaeseelandiae a b a c a a b a d b c b a a b a b a b a 15 collaris a b a c a a b a d c b b a a b b a a b a 16 fuligula a b a c a a b a d c c b a a b a b a b a 17 marila a b a c a b a a d b b b a a b a b a b a 18 affinis a b a c a b a a d c c b a a b a b a b a

Character

66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 Taxon d36 d37 d38 d39 d40 d41 d42 d43 d44 d45 d46 d47 d48 d49 d50 d51 d52 d53 d54 d55

I Ancestor a a a a a a a a a a a a a a a a a a a a 2 angustirostris a a a a a a a a b b a a a a a a a a a a 3 caryophyllacea b b b b a a a a b a b a a a a a a a b b 4 rufina b b b b a a a a b a a b b a a a a b a a 5 peposaca a a a a a a a b b a a a a b a a a a a a 6 erythrophthalma a a b b a a a a b a a a a a a a a a a a 7 ferina a a a a a a b a b a a a a a a a a a a a 8 americana a a a a a a b a b a a a a a a a a a a a 9 valisineria a a a a a a b a b a a a a a b a a a a a 10 australis a a a a c a a a b a a a a a a a a a a a 1 ! nyroca a a a a c a a a b a a a a a a b a a a a 12 innotata a a a a b a a a b a a a a a a a a a a a 13 baeri a a a a b a a a b a a a a a a a a a a a 14 novaeseelandiae a a a a b a a a b a a a a a a a a a a a 15 collaris a a a a a b a a b a a a a a a a a a a a 16 fuligula a a a a a b a a b a a a a a a a b a a a 17 marila a a a a a b a a b a a a a a a a a a a a 18 affinis a a a a a b a a b a a a a a a a a a a a

Character

86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Taxon d56 d57 d58 d59 d60 d61 d62 d63 d64 d65 d66 d67 d68 d69 A B C D

1 Ancestor a a a a a a a a a a a a a a a b a a 2 angustirostris a a a a a a a a a a a b a a a b a b 3 caryophyllacea a a a a b a a a b a b a a a c a ? b 4 rufina b a a b b b a a b a a a a a c b b b 5 peposaca a a a a b b a a b a a a a a c b b b 6 erythrophthalma a a a a b b a a b a a a a a b b b b 7 ferina a a a a b b b b a a a a b a b a b c 8 americana a a a a b b b b a b a a a a c b b c 9 valisineria a a a a b b b a a a a a a a c a b c 10 australis a a a a b b a a a a a a a a b b b c 11 nyroca a a a a b b a a a a a a a a a b b c 12 innotata a a a a b b a a a a a a a a ? ? ? ? 13 baeri a a a a b b a a a a a a a a b b b c January1996] Phylogenyof Pochards 93

APPENDIX 2. Continued.

Character

86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Taxon d56 d57 d58 d59 d60 d61 d62 d63 d64d65 d66 d67 d68 d69 A B C D

14 novaeseelandiae a a a a b b a a b a a a a a a a a/b c 15 collaris a b b a b b a a a a a a a b b b a/b c 16 fuligula a a a a b b a a b a a a a a b b a/b c 17 marila a a a a b b a a b a a a a a c b a c 18 affinis a a a a b b a a b a a a a a b b a c