Tuesday, April 17, 2018

[Ornithology • 2018] Distinctive Courtship Phenotype of the Vogelkop Superb Bird-of-Paradise Lophorina niedda Mayr, 1930 Confirms New Species Status

Cape presentation display of superba and niedda. The visual form of this display is the quintessential feature of courtship in the genus Lophorina

(A, C, E) Lophorina superba (Forster, 1781)
(B, D, F) Lophorina niedda Mayr, 1930

in Scholes​ & Laman, 2018. 
   DOI:  10.7717/peerj.4621 

Lophorina niedda Mayr, 1930

The birds-of-paradise (Aves: Paradisaeidae) are a quintessential example of elaborate ornamental diversification among animals. Ornamental evolution in the birds-of-paradise is exemplified by the presence of a highly integrated courtship phenotype, which is the whole package of plumage ornaments, behaviors and sounds that each species uses during courtship. Characterizing a species’ courtship phenotype is therefore a key part of evolutionary and taxonomic investigation in the group. With its unprecedented transmogrification from bird-like form into something abstract and otherworldly, the courtship phenotype of the Superb Bird-of-Paradise, Lophorina superba, is one of the most remarkable of all. Recent research by Irestedt et al. (2017) suggests that the genus Lophorina is not a single species but is likely a complex of three allopatric species spanning the island of New Guinea: L. niedda in the Bird’s Head Peninsula of the west, L. superba throughout the central cordillera and L. minor in the Papuan Peninsula of the east. Of these, niedda is the most phenotypically divergent with plumage traits hypothesized to possibly produce differences in ornamental appearance during display. However, the whole courtship phenotype of niedda has not been documented and so the actual extent of differences in ornamental appearance during courtship remain unknown. Here we analyze the first audiovisual recordings of niedda and compare its courtship phenotype with superba to test the hypothesis of potential differences in ornamental appearance. Our main goals are to: (1) provide the first description of the courtship phenotype of niedda in the wild, (2) determine if and how the niedda courtship phenotype differs from superba and (3) evaluate any uncovered differences in light of niedda’s newly recognized species status. Our secondary goal is to provide a more thorough characterization of courtship phenotype diversity within the genus Lophorina to facilitate future comparative study within the genus and family. Results show that the niedda courtship phenotype differs substantially from superba in numerous aspects of ornamental appearance, display behavior and sound. We highlight six key differences and conclude that the new species status of niedda is corroborated by the distinctly differentiated ornamental features documented here. With full species status, niedda becomes the fourth endemic bird-of-paradise to the Bird’s Head region of Indonesian New Guinea (i.e., the Vogelkop Peninsula), a fact that underscores the importance of this region as a center of endemic biodiversity worthy of enhanced conservation protection.

Figure 4: Pointing display of niedda as viewed by a female. The white arrow points to a female plumaged bird (and presumed female) observing the male on his display log. Note how the breast shield remains sleeked against the breast and is effectively invisible—its lateral tips concealed (shadowed) by the protruding “wings” of the cape. In this context, the eye-spots reflect so brightly relative to the super-black plumage of the rest of the male that they look like a pair of headlights “shining” toward the female. This “headlight pose” with the wing-like cape results in a very different appearance from the pointing display of superba. Image credit/source: Tim Laman/ML487540. 

Figure 5: Cape presentation display of superba and niedda. The visual form of this display is the quintessential feature of courtship in the genus Lophorina. In both superba and niedda (A and B), cape-flapping increases in intensity. In niedda (B), the increase is greater because the wings are lifted higher over the back and then flicked open and shut in the exaggerated manner of superba. Simultaneously, the breast is thrust forward so that the breast shield becomes fully expanded and conspicuous with its reflective surface angled toward the approaching female. In superba (C), the cape is lifted into presentation position before to female arrives on the log. In L. niedda (D), wing-flick/cape-flaps continue for several more bouts after the female arrives and before the cape is put into presentation position. The appearance of the cape presentation phenotype differs dramatically between superba (E) and niedda (F).

 Image credit/source: (A, C and E) Edwin Scholes/ML458003, (B) Tim Laman/ML487538 (D and F) Tim Laman/ML487557.

Given the substantial differences in so many aspects of the niedda courtship phenotype combined with the acute geographic isolation of niedda populations from superba populations, leaves little doubt that niedda deserves full species status as proposed by Irestedt et al. (2017).
The species validity niedda underscores the importance of Indonesian New Guinea’ Bird’s Head and Bird’s Neck eco-regions (i.e., the Vogelkop Peninsula) as a center of endemic biodiversity that deserves particular attention from the conservation community. Among birds-of-paradise alone, L. niedda now joins the three other montane species endemic to the region (Astrapia nigraParadigalla longicuda, and Parotia sefilata) and opens the door for additional systematic scrutiny of the entire avifauna of the Bird’s Head (Vogeklop) region, including the other birds-of-paradise at middle and upper elevations (e.g., Drepanonris albertisi and Epimachus fastosus). Given that the Bird’s Head region was the first part of New Guinea to be ornithologically explored, and discovery of new species of birds-of-paradise was the main driver of exploration, it is surprising that the distinctive features of the niedda courtship phenotype, and therefore the species status of this unique population, have remained elusive for so long. Yet this fact underscores the need for continued exploration of New Guinea’s forests and further systematic investigation of all taxa, including those like the avifauna which are often considered to be relatively well known.

Edwin Scholes​ and Timothy G. Laman. 2018.   Distinctive Courtship Phenotype of the Vogelkop Superb Bird-of-Paradise Lophorina niedda Mayr, 1930 Confirms New Species Status. PeerJ. 6:e4621.   DOI:  10.7717/peerj.4621

Martin Irestedt, Henrique Batalha-Filho, Per G. P. Ericson FLS, Les Christidis and Richard Schodde. 2017. Phylogeny, biogeography and taxonomic consequences in a bird-of-paradise species complex, LophorinaPtiloris (Aves: Paradisaeidae). Zoological Journal of the Linnean Society.  181(2); 439–470. DOI: 10.1093/zoolinnean/zlx004 

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