ORNITOLOGIA NEOTROPICAL 16: 387–396, 2005 © The Neotropical Ornithological Society

SYNTOPIC BREEDING SUGGESTS MIMICRY OF THE BLACK- AND-WHITE SEEDEATER (SPOROPHILA LUCTUOSA) BY THE BLACK-AND-WHITE TANAGER (CONOTHRAUPIS SPECULIGERA)

Christopher C. Witt1

Department of Biological Sciences and Museum of Natural Science, Louisiana State University, Baton Rouge, LA 70803, USA.

Resumen. – Reproducción sintópica sugiere que la Tangara Negriblanca (Conothraupis speculigera) mimetiza al Espiguero Negriblanco (Sporophila luctuosa). – En aves, el mimetismo visual interespecí- fico ha sido raramente documentado, aunque se han citado varios ejemplos. La similitud excepcional en los patrones de plumaje de dos especies simpátricas, la Tangara Negriblanca (Conothraupis speculigera) y el Espi- guero Negriblanco (Sporophila luctuosa), es un ejemplo potencial de mimetismo visual que no ha sido previa- mente reconocido. A diferencia del Espiguero Negriblanco, las características del plumaje de la Tangara Negriblanca no se encuentran en ninguna otra especie relacionada, sugiriendo que estas han convergido al patrón del Espiguero Negriblanco a través de selección natural. Además, la distribución reproductiva de la Tangara Negriblanca, aunque poco conocida, es ampliamente solapada por la del Espiguero Negriblanco, el cual es más abundante. Las observaciones presentadas aquí, que indican que la Tangara Negriblanca se reproduce entre agregaciones reproductivas del Espiguero Negriblanco, sugieren que la similitud conver- gente es un resultado de las interacciones interespecíficas. La diferencia en la abundancia de estas dos espe- cies sugiere convergencia evolutiva por un nuevo mecanismo en el que el imitador puede ser más grande que el modelo. Abstract. – Interspecific visual mimicry has rarely been well documented in birds, although numerous putative examples have been cited. The exceptional similarity in plumage pattern between the co-occurring Black-and-white Tanager (Conothraupis speculigera) and Black-and-white Seedeater (Sporophila luctuosa) is a potential example of visual mimicry that has not been previously recognized. Unlike the Black-and-white Seedeater, the plumage characteristics of the Black-and-white Tanager are found in none of its close rela- tives, suggesting that it may have converged on the pattern of the Black-and-white Seedeater through nat- ural selection. Furthermore, the breeding distribution of the Black-and-white Tanager, although poorly known, is extensively overlapped by the more abundant Black-and-white Seedeater. The observations reported here that the Black-and-white Tanager breeds among breeding aggregations of Black-and-white Seedeaters suggest that the convergent similarity is a result of interspecific interactions. The difference in abundance of these two species suggests evolutionary convergence by a novel mechanism whereby the mimic can be larger than the model. Accepted 18 April 2005. Key words: Black-and-white Seedeater, Black-and-white Tanager, Conothraupis speculigera, convergence, mimicry, Peru, Sporophila luctuosa. ______1Current address: Museum of Vertebrate Zoology, 3101 Valley Life Sciences Building, University of Califor- nia, Berkeley, California 94720-3160, USA. E-mail: [email protected]

387 WITT

INTRODUCTION converged on the Black-and-white Seedeater (Sporophila luctuosa) as a result of interspecific Intraspecific female mimicry (Slagsvold & interactions. Saetre 1991) and mimicry of brood hosts by brood parasites (Nicolai 1974) are well docu- EVOLUTIONARY CONVERGENCE mented forms of visual mimicry in birds. However, visual mimicry is also thought to Black-and-white Seedeater and Black-and- occur in response to social interactions white Tanager males are characterized by between species (Willis 1963, Moynihan 1968, black upperparts, wings, tail, head, throat, and Saetre et al. 1993). The best demonstration of upper breast (see Fig. 1). The lower breast, the latter phenomenon involves an oriole belly, flanks, and crissum are white. Each spe- (Oriolus) and a friarbird (Philemon), in which cies has white bases to the primary feathers parallel geographic variation is driven by that form a prominent spot (speculum) on interspecific antagonistic behavior (Diamond the side of the sitting bird, and a conspicuous 1982). Although it can provide irrefutable evi- white flash in flight. The subtle differences in dence of mimicry, parallel geographic varia- appearance between males of these two taxa tion is rare and should not be considered a are that the Black-and-white Tanager has gray prerequisite for the demonstration of inter- on the rump and sides, a concealed white specific visual mimicry, of which there are crown patch, red irides (not brown, as in the many putative examples (see Diamond 1982). Black-and-white Seedeater), a longer but pro- Interspecific visual mimicry can be reasonably portionally shallow bill, a darker gray culmen, inferred if three criteria are demonstrated: 1) and larger overall body size (Black-and-white evolutionary convergence in non-adaptive Tanager males, mean = 26.9 g, SD = 2.5, n = plumage traits of one species (the mimic) on 15; females, mean = 25.5 g, SD = 3.8, n = 12; another (the model), in a phylogenetic con- Black-and-white Seedeater males, mean = text; 2) overlap of the distribution of the 12.9 g, SD = 2.9, n = 6; females, mean = 11.1 mimic by the model sufficient that the model g, SD = 1.0, n = 3). Female plumages of each could comprise a significant selective force; species, also relatively similar, are a fairly uni- and 3) physical interaction or close proximity form, cryptic pale olive-brown color. Black- of the model to the mimic in nature. Species and-white Tanager females are slightly more pairs that satisfy these criteria would provide yellow with diffuse streaking on the under- ideal candidates for experimental tests that parts. seek to identify the cause of natural selection Although the genera Sporophila and Cono- for extreme similarity. thraupis were previously thought to be in sepa- In this paper, I present observations of rate families (Emberizidae and Thraupidae, breeding activity in the rare Black-and-white respectively), it is now recognized on the basis Tanager (Conothraupis speculigera) that docu- of genetic data that both genera are part of ment its occurrence amidst aggregations of the large Neotropical thraupine radiation Black-and-white Seedeaters (Sporophila luctu- (Tribe Thraupini; Bledsoe 1988, Sibley & Ahl- osa). While differing in size, these two species quist 1990). No exhaustively sampled, well- are extremely similar in plumage, and may resolved phylogeny exists for the Thraupini, represent an example of interspecific visual but the most comprehensive available molec- mimicry that has not been previously recog- ular phylogeny (Burns et al. 2002) indicates nized. I argue that the Black-and-white Tana- that 1) Sporophila is sister to Oryzoborus in ger (Conothraupis speculigera) may have clade with no other close relatives, and 2)

388 EXCEPTIONAL PLUMAGE SIMILARITY

FIG. 1. Comparison of the plumage pattern of the male Black-and-white Seedeater (top specimen in each panel) and the male Black-and-white Tanager. (A) Side view; (B) ventral view.

Conothraupis is sister to Chlorophanes, and entirely black and white male plumage), and nested in a clade containing 30 other genera. white wing specula are found in most Sporo- Black and white male plumage is common phila species (28 out of 32) as well as in the sis- among Sporophila (7 out of 32 species possess ter genus, Oryzoborus. Thus, the plumage

389 WITT pattern of the Black-and-white Seedeater is white Tanager on the Black-and-white Seed- not aberrant among members of its clade, and eater. is likely a result of its phylogenetic history. On An alternative explanation for the similar- the other hand, the apparent sister genus to ity in plumage between the Black-and-white Conothraupis is entirely green plumaged and Seedeater and the Black-and-white Tanager is lacks a wing speculum. Among the 30 other that they are subjected to similar selection genera in the Conothraupis clade, only 3 include pressures in common environments. Black species that possess black and white plumage, and white plumage has evolved independently and only 5 include species that possess wing many times in birds, and it is thought to con- specula. The distinctive black and white ceal birds from predators through disruptive plumage pattern and white wing speculum of coloration or countershading (Thayer 1909). Conothraupis appear to be synapamorphic, and It has also been suggested that black and not attributable to phylogenetic history alone. white plumage is associated with forest-edge From a phylogenetic perspective, the extreme habitats (Willis 1976). Contrasting wing mark- similarity in plumage between these two spe- ings are thought to be important in social sig- cies seems to be a result of the Black-and- naling (Butcher & Rohwer 1990), but have no white Tanager converging on the ‘typical known adaptive function. It is difficult to Sporophila’ plumage pattern of the Black-and- imagine that independent adaptive evolution white Seedeater. can account for the similarity in the precise Due to the overall uncertain resolution distribution of the black and white markings and incomplete sampling of the current between the Black-and-white Seedeater and Thraupini phylogeny (Burns et al. 2002), the Black-and-white Tanager. No other spe- more precise statistical tests of convergence cies in the New World shares the combination that depend on inference of ancestral of black back, wings, tail, head, and breast, character states could be misleading (Cun- and entirely white belly, vent, and speculum. ningham et al. 1998). It cannot be completely Furthermore, only two of 76 species that ruled out that Conothraupis is basal to the were found to co-occur with the Black-and- clade containing Sporophila and Oryzoborus. white Seedeater and the Black-and-white Tan- However, even if this scenario were true, it ager in a Peruvian tropical dry forest possess remains improbable that the precise resem- entirely black and white plumage, and those blance of the Black-and-white Tanager to species are heavily barred [Lined Antshrike the co-occurring Black-and-white Seedeater (Thamnophilus tenuepunctatus) and Fasciated would result from retention of ancestral Wren (Campylorhynchus fasciatus); unpublished character states. An additional caveat is pro- data]. vided by the mysterious sister-species to the Although the similarities of the Black-and- Black-and-white Tanager, the Cone-billed white Tanager to the Black-and-white Seed- Tanager (C. mesoleuca), which shares the eater can be explained by convergence, the same basic plumage pattern. The Cone-billed differences in bill shape and eye color can be Tanager is known from a only single speci- attributed to phylogenetic history. Chlo- men collected in 1938 in Mato Grosso, rophanes, the apparent sister genus to Cono- Brazil, and it is thought to be extremely thraupis, possesses a red eye, as do species in closely related to the Black-and-white Tanager several other genera in the Conothraupis clade (Zimmer 1947). It is possible that the (LSUMZ specimen data). In addition, all taxa divergence between these two species in the Conothraupis clade possess bills that are post-dated the convergence of the Black-and- proportionately longer and shallower than

390 EXCEPTIONAL PLUMAGE SIMILARITY ------molt Body Light Light Light Trace Trace Trace None None None None None None None None None Heavy Heavy Heavy Moderate Moderate acocha, collectedacocha, in ------n Imm. Imm. Imm. Imm. Imm. Imm. Imm. Imm. Imm. Imm. Imm. Adult Adult Adult Plumage Intermediate allpa, collected in 1987; (5) c n-American Hwy., 11 km by n-AmericanHwy., a ------Iris Red Red Red color Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown Brown - - es as follows: (1) Peru: Loreto, Pucallpa, Yari Pucallpa, Loreto, (1) Peru: follows: es as Ovary 4 mm Testes 1 mm Testes 1.5 mm Testes Testes 1 x 1 mm Testes 1 x 1 mm Testes 2 x 1 mm Gonad condition Testes 1 x 0.5 mm 1 x 0.5 Testes mm 1 x 0.5 Testes mm 1 x 0.5 Testes mm 1.5 x 1 Testes mm 1.5 x 1 Testes mm 1 x 0.5 Testes mm 1 x 0.5 Testes Testes 0.5 x 0.5 mm x 0.5 0.5 Testes Left testis 2 x 1 mm Testes < 1 mm diameter mm 1 < Testes Ovary 5 x 2 mm, smooth, oviduct minute oviduct Ovary 5 x 2 smooth, mm, minute oviduct Ovary 4 x 2 smooth, mm, minute oviduct Ovary 4 x 3 smooth, mm, minute oviduct Ovary 5 x 3 smooth, mm, minute oviduct Ovary 4 x 3 smooth, mm, Ovary 1 5 mm x 2.5 oviduct mm, smooth, Ovary minute mm, smooth, oviduct 2.5 x 2 Ovary 5 x 3 mm, ova minute, oviduct 2 mm oviduct minute, Ovary 5 x 3 mm, ova Ucayali, westernUcayali, bank 65 km east-northeast Rio Shesha, c. Pu of d in 1963 or 1967; (3) Peru: Lambayeque, Las Pampas, kmP 885 d in 1963Las Pampas, or 1967; (3) Peru: Lambayeque, ------0 0 0 0 10 50 50 10 10 15 50 80 10 10 10 20 20 100 100 100 % skull ossification ------Fat Light Light Light Trace None None Heavy Heavy Heavy Heavy Moderate Moderate Moderate Moderate Moderate Very heavy Very heavy Very heavy Very heavy Very heavy ------(g) 26.0 26.0 24.0 29.5 23.5 24.0 22.5 24.0 22.0 30.5 25.5 26.0 29.5 33.0 27.0 29.0 30.0 27.0 29.0 23.0 Mass k-and-white Tanager specimens at LSUMNS. Localiti specimens k-and-white at LSUMNS. Tanager F F F F F F F F F F F M M M M M M M M M M M M M M M Sex Date 2 Sep 3 Sep 3 Sep 3 Sep 3 Sep 3 Sep 3 Sep 5 Sep 31 Jul 31 Jul 28 Jul 25 3 Aug 1 Aug 28 Jun 10 Sep 10 Sep 10 Sep 10 Sep 10 Sep 14 Sep 15 Sep 15 Sep 15 Sep 15 Sep 30 Aug 31 Aug 1 1 1 1 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 Locality Cat. 28636 28637 28638 28639 31456 62602 113916 113917 113918 113919 113920 113921 113922 113923 113925 113926 113927 113928 113929 113930 113931 113932 113933 113934 113935 113936 number TABLE 1. Specimen data for Blac TABLE collecte Rio300 Curanja, m a.s.l., Balta, (2) Peru: Loreto, 1962; collected in 1983; 150 (4) Peru:road north m a.s.l., of Olmos, collected in 450 1999. m a.s.l., Peru:78°46’W, Cajamarca, junction and Rio5°23’S, Chinchipe, of Rio Tabaconas

391 WITT molt Trace Trace None None None None None Moderate - - - - Imm. Imm. Imm. Adult Plumage Body Red Red color Brown Brown Brown Brown Brown Brown Testes 1 x 1 mm Gonad condition Iris Testes 1 x 0.5 mm 1 x 0.5 Testes mm 1.5 x 1 Testes Left testis 5 x 3 mm Ovarymm, smooth 2 x 3 Ovary 6 x 4 mm, ova and oviduct minute and oviduct ova 4 mm, 6 x Ovary Ovary 4 x 3 mm, smooth, oviduct minute oviduct Ovary 4 x 3 smooth, mm, Ovary minute mm, smooth, oviduct 2.5 x 2 20 10 50 10 10 25 90 100 ossification - Fat skull % Light Light Light Heavy Moderate Moderate Moderate (g) 27.5 25.0 26.0 27.0 28.0 20.0 20.0 24.5 F F F F M M M M 8 Jul 1 Aug 15 Sep 15 Sep 18 Sep 19 Sep 21 Sep 15 Feb 3 3 3 3 3 4 4 5 Locality Date Sex Mass Cat. 113937 113938 113940 113941 113943 156823 156824 number CCW408 TABLE 1. 1. Continuation. TABLE

392 EXCEPTIONAL PLUMAGE SIMILARITY that of the Black-and-white Seedeater (and all Andean valleys (Ridgely & Greenfield 2001, Sporophila and Oryzoborus species). pers. observ.). During the non-breeding sea- son, it disperses from breeding sites, often in DISTRIBUTIONAL OVERLAP large flocks, and becomes somewhat nomadic.

The distribution of the Black-and-white Tana- PHYSICAL PROXIMITY AT BREED- ger has long been an enigma (O’Neill 1966). ING SITES The scant existing data indicates that it breeds during the middle to latter part of the rainy In February 1999, while conducting an inven- season (which lasts approximately December tory of birds in a tropical deciduous forest in to May) in seasonally arid areas on the west Depto. Cajamarca, Peru, I found Black-and- slope of the Andes and in inter-Andean val- white Tanagers and Black-and-white Seedeat- leys in southern Ecuador and northern Peru. ers occurring together in hillside forest clear- During the dry season (approximately June to ings with grass and dense scrub. All November), the Black-and-white Tanager is observations were made within 3 km of the not present at breeding sites (Ridgely & junction of the Tabaconas and Chinchipe Riv- Greenfield 2001, pers. observ.), and the scat- ers, which lies on the east slope of the Andes, tered records indicate that it disperses into but in the rain shadow of the southernmost humid lowland Amazonia in southern Ecua- extent of the Cordillera del Condor (5º23’S, dor, eastern Peru, northwestern Bolivia, and 78º46’W; 400-600 m a.s.l.). The Black-and- western Brazil (O’Neill 1966, Isler & Isler white Seedeater was abundant, whereas only 1987, Stotz 1990). However, during August five individuals of the Black-and-white Tana- and September 1983, when El Niño-related ger were observed during a 6-day period. I precipitation caused normally arid areas on found Black-and-white Seedeaters to be con- the west slope of the Andes to become cov- centrated in loose colonies, or breeding aggre- ered with verdant vegetation, the Black-and- gations, where appropriate habitat (patches or white Tanager was found in large numbers at clearings with grass and dense scrub) was localities where normally rare or absent (S. W. present. Black-and-white Seedeater males Cardiff & D. L. Dittmann, in Isler & Isler sang from elevated perches in these habitat 1987). Thus, existing data suggest that non- patches, creating a cacophony of blackbird- breeding Black-and-white Tanagers are some- like, high-pitched song. In two such patches, I what nomadic and exploit seasonal or spo- found single Black-and-white Tanager males radic resources. Among a series of 33 within aggregations of Black-and-white Seed- specimens collected between June and Sep- eaters, singing from elevated perches. In tember, from both east and west of the another Black-and-white Seedeater aggrega- Andes, none appear to be in breeding condi- tion, two singing Black-and-white Tanager tion on the basis of specimen label data (Table males were present on opposite sides of a 1). grassy clearing. In all cases, the Black-and- The distribution of the Black-and-white white Seedeater far outnumbered the Black- Seedeater encompasses most of the known and-white Tanager. The song of the Black- breeding distribution of the Black-and-white and-white Tanager was similar in tone to that Tanager, but also extends from Venezuela to of the Black-and-white Seedeater, but easy to Bolivia. Like the Black-and-white Tanager, it detect among the din of song because each breeds during the rainy season on both slopes phrase concluded with a clear, lower-pitched, of the Andes and in seasonally dry Inter- whistled note (song described in Isler & Isler

393 WITT

1987). Antagonistic encounters were blance of orioles to friarbirds reduced the observed among Black-and-white Seedeater frequency or severity of interspecific antago- males, but no interspecific antagonism was nistic encounters. As a result, orioles that observed. The Black-and-white Tanager closely resemble friarbirds are expected to males were observed on multiple occasions experience increased survival or reproduc- dropping from their singing perches to forage tion. I suggest that a similar mechanism is on or near the ground in close proximity to occurring in the Black-and-white Tanager and foraging Black-and-white Seedeaters. One the Black-and-white Seedeater, whereby individual was observed carrying out an Black-and-white Tanager individuals that extended preening bout on an exposed dead closely resemble Black-and-white Seedeater branch. A female Black-and-white Tanager incur a selective advantage. was observed foraging in dense scrub, at the Diamond (1982) posited that social mim- edge of a clearing with an aggregation of icry should only evolve when the mimic is Black-and-white Seedeaters. Voucher speci- smaller than the model and thus benefits dif- mens of both the Black-and-white Tanager ferentially from the reduction in antagonism. (CCW408) and the Black-and-white Seedeater Therefore, it seems paradoxical that the (CCW417) were collected. The pattern of ter- Black-and-white Tanager is larger than the ritorial advertisement song and the enlarged Black-and-white Seedeater. I argue that, given testes on the single collected specimen sug- that antagonistic encounters have an energetic gest that Black-and-white Tanagers were cost to both winner and loser, selection for breeding at these sites (left testis 5 x 3 mm; reduction of interspecific antagonism could testes of three adult male Black-and-white be stronger in the less abundant species, Tanager specimens collected between June regardless of relative size. The Black-and- and September range from 1.5 mm diameter white Tanager, which is generally considered to 2 x 1 mm; Table 1). rare, is less abundant than the Black-and- white Seedeater by at least an order of magni- DISCUSSION tude at the observed sites of co-occurrence in the Chinchipe River Valley. The two species In most described cases of animal visual mim- occupy the same habitat patches and foraging icry (Batesian or Müllerian mimicry), the stratum, suggesting that they are in competi- mimic converges on the appearance of the tion for resources such as food and nest sites. model in order to affect the response of a The extreme similarity and larger size of the potential predator, the intended signal Black-and-white Tanager may allow it to be receiver (Wickler 1968). If the Black-and- more readily recognized by the Black-and- white Seedeater, the model, is toxic or dis- white Seedeater as a dominant competitor, tasteful to predators, convergence by the reducing the need for interspecific aggression. Black-and-white Tanager could be the result This would allow Black-and-white Tanagers of Batesian or Müllerian mimicry (Dumb- to defend resource patches or establish inter- acher & Fleischer 2001). However, no evi- specific territories (sensu Cody 1969) without dence (such as aposematic coloration) expending energy chasing naïve Black-and- suggests that either species is toxic. In the white Seedeater individuals. case of the orioles and friarbirds, the smaller Convergent plumage patterns, overlap- mimic (oriole) converges on the larger model ping distributions, and physical proximity on (friarbird) to deceive the model itself. Dia- breeding sites suggest that the Black-and- mond (1982) suggested that visual resem- white Tanager is a visual mimic of the Black-

394 EXCEPTIONAL PLUMAGE SIMILARITY and-white Seedeater, and that the similarity in Phylogenetic relationships and morphological plumage has a function relating to interspe- diversity in Darwin’s finches and their relatives. cific behavior. Additional fieldwork is needed Evolution 56: 1240–1252. to test this hypothesis using behavioral obser- Butcher, G. S., & S. Rohwer. 1990. The evolution vations, experimental tests, and more data on of conspicuous and distinctive coloration for communication in birds. Curr. Ornithol. 6: 51– the breeding distribution and life history of 108. the rare and enigmatic Black-and-white Tana- Cody, M. L. 1969. Convergent characteristics in ger. sympatric species: a possible relation to inter- specific competition and aggression. Condor ACKNOWLEDGEMENTS 71: 222–239. Cunningham, C. W., K. E. Omland, & T. H. Oak- Fieldwork was supported by a grant from the ley. 1998. Reconstructing ancestral character Committee for Research and Exploration of states: a critical reappraisal. Trends Ecol. Evol. the National Geographic Society to John P. 13: 360–366. Diamond, J. M. 1982. Mimicry of friarbirds by ori- O'Neill (Grant #6234-98), and through funds oles. Auk 99: 187–196. donated to the Tropical Research and Explo- Dumbacher, J. P., & R. C. Fleischer. 2001. Phyloge- ration Fund of the LSU Foundation by Mr. netic evidence for colour pattern convergence and Mrs. Robert B. Wallace. Permits were in toxic pitohuis: Müllerian mimicry in birds? P. issued by the Instituto Nacional de Recursos Roy. Soc. Lond. B 268: 1971–1976. Naturales (INRENA) del Ministerio de Agri- Isler, M. L., & P. R. Isler. 1987. The tanagers: natu- cultura, Lima, Peru. For issuance of the per- ral history, distribution, and identification. mits, I thank Dr. Miguel Ventura N. and Smithsonian Institution Press, Washington, D. Rosario Acero V. I thank our colleagues at the C. Museo de Historia Natural de la Universidad Moynihan, M. 1968. Social mimicry; character con- Nacional de San Marcos (MUSM) in Lima, vergence versus character displacement. Evolu- tion 22: 315–331. especially Dr. Irma Franke J. I received valu- Nicolai, J. 1974. Mimicry in parasitic birds. Sci. Am. able assistance from José Campos, Camilo 231: 92–98. Diaz, Robert C. Faucett, Isabel Gomez, P. O’Neill, J. P. 1966. Notes on the distribution of Gabriela Ibañez-Hernandez, Daniel F. Lane, Conothraupis speculigera (Gould). Condor 68: Kazuya Naoki, John P. O’Neill, Manuel 598–600. Sánchez S., Marta Sánchez de Chávez, Abra- Ridgely, R. S., & P. J. Greenfield. 2001. The birds of ham Urbay T., and Rodolfo Vásquez Mar- Ecuador: status, distribution, and taxonomy. tínez. S. W. Cardiff and D. L. Dittmann Cornell Univ. Press, Ithaca, New York. collected an important series of Conothraupis Sibley, C. G., & J. E. Ahlquist. 1990. Phylogeny and specimens in Lambayeque, Peru, in 1983. S. classification of the birds of the world. Yale M. Witt, J. V. Remsen, Jr., and two anonymous Univ. Press, New Haven, Connecticut. Saetre, G.-P., M. Kral, & V. Bicik. 1993. Experi- reviewers provided critical comments on the mental evidence for interspecific female mim- manuscript. icry in sympatric Ficedula flycatchers. Evolution 47: 939–945. REFERENCES Slagsvold, T., & G. P. Saetre. 1991. Evolution of plumage color in male Pied Flycatchers Bledsoe, A. H. 1988. Nuclear DNA evolution and (Ficedula hypoleuca): evidence for female mimicry. the phylogeny of the New World nine-prima- Evolution 45: 910–917. ried oscines. Auk 105: 504–515. Stotz, D. F. 1990. Corrections and additions to the Burns, K. J., S. J. Hackett, & N. K. Klein. 2002. Brazilian avifauna. Condor 92: 1078–1079.

395 WITT

Thayer, G. H. 1909. Concealing-coloration in the Willis, E. O. 1976. Similarity of a tyrant-flycatcher animal kingdom. Macmillan Co., New York, and a silky-flycatcher: not all character conver- New York. gence is competitive mimicry. Condor 78: 553. Wickler, W. 1968. Mimicry in plants and animals. Zimmer, J. T. 1947. Studies of peruvian birds. No. Translated from the German by R. D. Martin. 52. The genera Sericossypha, Chlorospingus, Cne- McGraw-Hill, New York, New York. moscopus, Hemispingus, Conothraupis, Chlorornis, Willis, E. O. 1963. Is the Zone-tailed Hawk a Lamprospiza, Cissopis, and Schistochlamys. Am. mimic of the Turkey Vulture? Condor 65: 313– Mus. Novit. 1367: 1–26. 317.

396