Phasianidae: Francolinus)
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The Auk 109(1):24-42, 1992 PHYLOGENETIC, TAXONOMIC AND BIOGEOGRAPHICAL IMPLICATIONS OF GENETIC, MORPHOLOGICAL, AND BEHAVIORAL VARIATION IN FRANCOLINS (PHASIANIDAE: FRANCOLINUS) TIMOTHY M. CROWE,• ERIC H. HARLEY,2 MARIOLAB. JAKUTOWICZ,•'2 JORISKOMEN, 3'• AND ANNA A. CROWE1 •FitzPatrickInstitute, University of CapeTown, Rondebosch 7700, South Africa; 2Departmentof ChemicalPathology, University of CapeTown, Rondebosch7700, South Africa; and 3Departmentof Birds,State Museum of Namibia,Box 1203, Windhoek, Namibia ASSTRACT.--Westudied restriction-fragment length polymorphisms (RFLPs) in mitochon- dria! DNA for 13 speciesof African franco!ins(Francolinus spp.) and the JapaneseQuail (Coturnixc. japonica). Phylogenetic analyses of RFLPsfor these14 speciesand of morphological and behavioralcharacters for the 41 francolinspecies and other perdicinetaxa do not confirm the monophylyof Francolinusas currently recognized.Analyses of morpho-behaviora!char- acters suggestthat Francolinusconsists of at least four major assemblages:the five Asiatic species;two groupsof Africanquail-like species; and the Africanpartridge-like species. Within theseassemblages, analyses of RFLPsand/or morpho-behaviora!characters support the mono- phy!y of six of eight speciesgroups attributed to Francolinus.Assuming the monophy!yof currently recognizedsupraspecific groups of ga!!iformbirds, morphometricanalyses of gal- !iform skeletonscorrectly classified 90-99% of specimensto family, subfami!yand tribe, as well as 95% of the francolin specimensto genus. Genetic distancesderived from RFLP data imply thatAfrican francolinsdiverged from their sistertaxa at or beforethe mid-lateMiocene, and that a!! speciesstudied diverged from their sister-speciesduring the Plioceneor early Pleistocene.Received 29 June1990, accepted 13 July 1991. THESUPRASPECIFIC phylogenetic relationships skeletalanatomy has led to a proliferation of amongmembers of the family Phasianidae(sen- small genera(mean phasianidspecies-to-genus su Morony et al. 1975) remain poorly resolved ratio = 3.3; range = 1-41; Morony et al. 1975) (Verheyen 1956,Cracraft 1981,Stock and Bunch of uncertainphylogenetic affinity (Olson 1985). 1982,Gutierrez et al. 1983,Sibley and Ahlquist The most striking exception to this "small- 1985,Helm-Bychowski and Wilson 1986,Crowe genus rule" in the Phasianidaeis the genus 1988,Randi et al. 1991).A primary causeof this Francolinus.The francolins form the largest ge- phylogenetic uncertainty is that, while the di- nus in the Galliformes(Morony et al. 1975)and agnostic morphological and behavioral attri- one of the largestgenera in the classAves (Bock butes (hereafter termed morpho-behavioral and Farrand 1980). Hall (1963:109;Fig. 1A) rec- characters)of phasianidsupraspecific taxa tend ognized 41 speciesof francolins (36 African, 5 to be highly divergentqualitatively, differences Asian) and concluded that francolins form a in the skeletalanatomy of thesetaxa tend to be single, monophyletic genus, the members of subtle and continuous.For example, although which are distinguishablefrom other members Steadman(1980) was able to assignavian fossil of the Perdicini (sensuMorony et al. 1975) by bones to various speciesof turkeys (Meleagri- a long, hooked bill, a short tail of 14 feathers, dinae) by a relatively simple morphometricap- an upright stanceand, in the majorityof species, proach,only a few of the more than 100 skeletal spurs at least in the males. charactershe employed qualitatively distin- Hall (1963:110)proposed the monophyly of guish turkeys from other phasianids.Because Francolinusand then partitioned all but four osteologicalcharacters are among the more im- species(F. lathami,F. pondicerianus,F. nahani, and portant diagnosticfeatures used to assignspe- F. gularis)of this assemblageinto eight mono- cies to avian genera, this marked divergence in phyletic groups,seven of which have represen- external morphology and relatively conserved tatives in Africa (Fig. 1A). Hall (1963:170)fur- 24 January1992] EvolutionofFrancolins 25 QUAIL-FRANCOUNS PARTRIDGE-FRANCOLINS 11 26 C•ow• ETA[. [Auk, Vol. 109 ther suggested that the genus may have and Milstein and Wolff's (1987) quail- and par- originatedin Asiaduring the Oligocene(ca. 25- tridge-francolins(Fig. 1A); (2) determine the 35 x 106y.b.p.), and that extant speciesof Af- degreeof geneticvariation within and between rican francolins diverged from their sister spe- certain(primarily southern)African francolins; cies perhaps as recently as the last 10,000 to (3) estimatethe evolutionarydivergence times 100,000 years. of the genusFrancolinus and its componenttaxa; Milstein and Wolff (1987) argued for parti- (4) comment on the taxonomic and biogeo- tioning Francolinusinto two major clades com- graphical implications of these results;and (5) prising quail-like and partridge-likebirds (Fig. assessthe correlation between speciesgroup- 1A). "Quail-francolins"(called patryseby Mil- ings suggestedby morphometric, morpho-be- stein and Wolff 1987) are generally small, havioral,and geneticinformation for galliforms ground-roostingbirds with striped and barred in general and francolins in particular. rufousdorsal plumage resembling that of quails (Coturnixspp.); they have high-pitched, tonal METHODS AND MATERIALS calls. "Partridge-francolins"(called fisanteby Milstein and Wolff 1987) are generally larger, MtDNA datacollection and analysis.--Liver tissue was tree-roosting birds with dark dorsal plumage excisedfrom one specimenof the JapaneseQuail and vermiculatedwith white or buff; they give low- eachof the 13 African francolin species(Table 1) and frozen in liquid nitrogen. Tissue from additional er-pitched, raucouscalls (Milstein and Wolff specimensof F. africanusand F. levaillantiiwas col- 1987).Taxonomically, following Wolters(1975 ), lectedat sites400-700 km from the original collection Milstein and Wolff split the southern African localities(Table 1) to assessgeographical variation in speciesinto four genera (Fig. 1A). mtDNA structure. In a preliminary phylogeneticstudy of fran- MtDNA from each specimenwas extractedfrom colin morphology and behavior, Crowe and about 4 g of whole tissue (Brown 1980, as modified Crowe (1985) failed to corroborate the mono- by Densmoreet al. 1985). We used 14 restrictionen- phyly of Francolinus.However, they confirmed donucleases:EcoRI, ScaI, SacI, SacII, PvuII, StuI, HindIII, the monophyly of Hall's Spotted,Red-winged, NcoI, BamHI, BclI, PstI, EcoRV, Asp 718, and XbaI. Red-tailed,Bare-throated and Montane groups, Conditions for restriction-endonucleasedigestions were those suggestedby the suppliers(Amersham as well as that of Milstein and Wolff's (1987) International,Boehringer Mannhelm, New England partridge-francolins(Fig. 1A). Crowe and Crowe Biolabs).We end-labeledmtDNA fragmentswith 32p_ (1985) also concludedthat quail-francolinsare dCTP by incubation with the Klenow fragment of a paraphyletic assemblage.Based primarily on DNA polymeraseI at 25øCfor 10 min to exposead- ontogenetic information, Crowe and Crowe ditional nucleotidesfrom fragmentswith blunt ends (1985) hypothesized that the ancestor of the or 3' overhangs.The fragmentswere incubatedfor francolinswas a small, quail-like phasianid,be- an additional 10 min after addition of unlabeled DTTP, causeplumage and other integumentary fea- dATP and dGTP plus 32P-dCTP.The labeled frag- tures (e.g. bill and tarsus color) of immature mentswere separatedby electrophoresisthrough 1.2% francolinsare remarkablyquail-like (Crowe et horizontal agarosegels in 1 x TAE buffer that in- cluded0.05% pyrophosphate. Gels were visualizedby al. 1986). Taxonomically,on the strength of autoradiography.Lambda phage DNA digestedwith overall morphometric osteologicalsimilarities HindIII was used as a molecular-weightmarker. amongfrancolins, Crowe and Crowe (1985)pro- We assessedrestriction-fragment length polymor- visionally kept the francolinsin one genus,but phism (RFLP) in mtDNA from restriction-endonu- proposeda systemof subgenerasimilar to that cleasefragment patterns, assumingthat fragments of Wolters (1975). with the same electrophoreticmobility are homolo- In this paper, we discussstudies of: (1) the gousbetween haplotypes.The percentageoverall nu- mitochondrial DNA (mtDNA) of 13 speciesof cleotidedivergence (b) between haplotypeswas es- African francolins and of the JapaneseQuail timated in a pairwisemanner by the iterative method (Coturnixcoturnix japonica); (2) the morphology of Nei (1987). Due to the large number of francolin speciesex- and behavior of the 41 speciesof francolins and amined, it was not feasible to map restriction sites. a range of other perdicine species;and (3) the Therefore, we used RFLPs as characters. We realize morphometricsof a representativerange of gal- that this involvesa potentialloss of phylogeneticin- lifotins (including 25 Francolinusspecies). Our formation (Swoffordand Olsen 1990),but RFLPsare aimsare to: (1) reassessthe monophylyof Fran- alsolegitimate synapomorphies in phylogeneticanal- colinus,Hall's (1963) francolin speciesgroups, ysis(Zink and Avise 1990).Therefore, phylogeneti- January1992] Evolutionof Francolins 27 TAISLE1. Speciesand sourcesof specimensused in mtDNA analysis. Species Locality Coturnixc. japonica Domestic bird. F rancolinus leucoscepus Athi River District, Kenya. levaillantii Sable District, Transvaal, and Giants Castle Nature Reserve, Natal. levaillantoides Balfour District, Transvaal. natalensis Sable District, Transvaal. adspersus Omaruru District, Namibia. sephaena Nylstroom District, Transvaal. Uitenhage