Proposal (111) to South American Classification Committee
The following is a copy of Dick Banks's proposal in 2001 to AOU checklist Committee, which passed; I here convert it to a SACC proposal, with Dick's permission. This proposal was to treat meloda as a separate species, which we already do; therefore, a "YES" vote is to reverse the outcome of the AOU decision, and a "NO" vote means stick with what we have in SACC.
Lump Zenaida meloda into Z. asiatica
Dick Banks's AOU proposal to split Zenaida meloda and Z. asiatica:
Johnson and Clayton (2000) have shown that the South American Zenaida meloda, which we currently treat as a group within Z. asiatica, deserves treatment at the species level. In a study of mitochondrial and nuclear DNA sequences, they state:
"The level of mitochondrial genetic divergence between the Central and North American Z. asiatica and the South American Z. meloda (4.2%) is high in relation to a mere 0.09% divergence between White-winged Doves from Arizona and Texas. The split between Z. asiatica and Z. meloda also is recovered using the slowly evolving nuclear gene. These high divergences would generally only accumulate under long periods of no gene flow between populations and indicate that Z. meloda should be recognized as a separate species from Z. asiatica. Although the plumage of these two species is quite similar, Z. asiatica and Z. meloda differ in soft-part coloration and in vocalizations, further supporting their species status (Baptista 1997)."
The latter reference is to the HBW account, where it merely mentions (in the species accounts) but does not specify "differences in vocalizations and morphology. "Z. meloda s larger than Z. asiatica. This split is also recognized by Gibbs et al. (2001), who merely note that there are vocal and morphological differences.
Johnson, K. P., and D. H. Clayton. 2000. A molecular phylogeny of the dove genus Zenaida: Mitochondrial and nuclear DNA sequences. Condor 102:864-870.
Gibbs, D., E. Barnes, and J. Cox. 2001. Pigeons and doves. A guide to the pigeons and doves of the world. Yale University Press.
Richard Banks, to AOUCLC in 2001
Comments from Remsen to AOU CLC in 2001: "This NO vote is largely on principle, because I'm certain that these are good species. However: (1) the actual data are not published on the differences in voice and soft part colors and whether these indicate species-level divergence in Zenaida; (2) the % sequence difference is large but, to me, indicates nothing in itself other than long isolation, which we knew already from biogeography; my response to Johnson-Clayton would be ... if you regard 4.2% difference as species-level, what about 4.1, what about 4.0, what about 3.9 .... and so on ... to make the point that these levels cannot be used alone as indicators of taxonomic status."
Comments from Stotz to AOUCLC in 2001: "YES. I understand Van's hesitation, but my feeling is that meloda is clearly a separate species. Even though the publication of that justification has been limited, I think, given that it is extralimital and hugely disjunct, that it is worth going ahead and becoming consistent with other treatments. I don't think anybody would argue that it isn't likely to be a distinct species. We can hang the change on the degree of genetic differentiation perhaps, which is about equal to the distance from Mourning Dove to Eared Dove, but I agree that is insufficient by itself. However, there are a variety of characters which separate meloda from asiatica. The voice of course is the most obvious. Unfortunately I can't find that anybody has directly compared it in print (except to say that it is very different, which it is). However, Ridgely's new Birds of Ecuador will describe it, and it is on the Hardy tape for Pigeons and Doves, along with a Guerrero cut of asiatica. Maybe we should refer to the Hardy tape. In terms of the morphology, meloda is larger in basically all measurements (Cottom and Trefethen 1968, Whitewings), and HBW gives a weight of 216 (which comes from Tubaro and Mahler 1998 Condor 100:54-61) versus 125-187 for asiatica (Dunning is source of that). The soft part differences are described by HBW (eye color brown in meloda versus red in asiatica, brighter blue bare orbital skin), but their significance is, as Van notes, not shown. HBW also talks about a number of plumage differences. Although these are minor, they place meloda well outside the variation within northern White-winged Doves. These include: lack vinaceous color on crown and nape, face and nape pinkish gray rather than buffy, so less contrast with gray abdomen, tail tips pale gray rather than white (these are also smaller by about 50%). They don't mention the fact that the black face mark is reduced (I admit that FMNH has only 5 meloda, so this may not be as general as I think).
"So while I would prefer that we have a detailed analysis of why this is a separate species, given that meloda is widely disjunct, so no natural test will be forthcoming and it has a large genetic distance from asiatica, has a series of plumage and morphological differences that place it outside the range of the other subspecies, and has a distinctive voice compared to a species that otherwise seems to sound the same everywhere (Arizona, Texas, Florida, Cuba, and Guerrero at least, and at least to my tin ear), I think splitting Zenaida meloda can be justified. The Hardy reference is Hardy, J.W., G. B. Reynard, and B. B. Coffey. 1989. Voices of the New world Pigeons and Doves. ARA Records, Gainesville. "
Reminder -- "NO" = retain meloda as species, "YES = lump with asiatica
Comments from Remsen: "Doug's analysis above from 2001 convinced the AOU CLC to adopt the change, and I may have switched my vote as well. If only the published studies had taken the time that Doug did to synthesize the pros and cons ... anyway, this time I vote 'NO,' i.e. stick to our current taxonomy and treat meloda as a separate species."
Comments from Stiles: "This is another one where the original lumping was less than convincing, so keeping them separate seems best - published recordings do exist and are decidedly distinctive (especially in the context of the Columbidae) and could easily serve as isolating mechanisms, the morphology differs considerably and the genetic and geographical data, while not conclusive, also tend in this direction - so, NO. "
Comments from Nores: "NO, estoy de acuerdo con la propuesta de Dick Banks y Douglas Stotz de separar ambas especies, lo cual es apoyado principalmente por diferencias genéticas, pero también por coloración de las partes desnudas (soft parts) y vocalizaciones."
Comments from Jaramillo: "NO. The genetic data along with voice differences (pers. obs.) are enough for me. The taxon meloda actually sounds quite different from the "Who cooks for you" song of asiatica. I (Birds of Chile) described it as: "A repeated Hooo-hoodoodle Hooop-hooodoodle Hooop-hooodoodle."
Comments from Zimmer: "NO. I think there is enough in the published realm to justify treating the two as separate species, and I have no doubt that the vocal differences alone are enough to isolate these forms. After having lived with White-winged Doves for 10 years in Texas/New Mexico (and continuing to deal with them in Arizona and Costa Rica on a yearly basis ever since), it was a shock to me the first time I awoke in a hotel room in Lima wondering what the melodic sound outside my window was, only to part the drapes and see a Z. meloda sitting on the railing. The song wasn't even remotely recognizable to me."