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.
Literature Cited
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."