Home About Committees North American Classification Committee Current & Prior Proposals 2020 Proposals Comments 2020-A

Comments 2020-A

2020-A-1: Change the English name of Olive Warbler Peucedramus taeniatus to Ocotero

YES (weakly). Overall, I do like the proposed name Ocotero, I find it is very fitting, and does fall under the new Guidelines for English Bird Names (section C.4). However, my only concern, and the only reason this is a “weak” yes vote, is that section C.4 does specifically mention that some names, including warbler, have no phylogenetic significance at the family level, and are best treated as morphotypes. In support of this point, warbler is already used widely around the world (10 families worldwide, not including the present species), and it is a widely recognized morphotype, and thus conveys some level of description in and of itself, even if it’s of no taxonomic value. But, on the flip side, at least on a North American level (and entire New World), renaming Peucedramus taeniatus would restrict the use of “warbler” and would restore some taxonomic value back to warbler in the New World.

YES. I think the motion is well-formulated and the English name change would be informative. It is a bit of a stretch, but there is some olive on the crown and flight feather edges, and, a bit in the face on female and young male “Olive Warblers.” The new name would reflect the fact that 90% or more of the range is south of the U.S. southern border, and it apparently reflects their habitat preference. I would add that on occasion it is worth making a change to convey information. I’ll return back to an issue that has been troubling me for a number of years, namely that the species in the U.S. and Canada we call “tanagers” aren’t tanagers, and the only ones that are tanagers (five) aren’t called tanagers. Two of the most experienced birders in North America had no idea that what we call tanagers weren’t in Thraupidae. I would venture to guess then that this applies to 99% of the North American birding community. Seriously, I would have proposed we call them Scarlet Piranga and so forth (think that we used this philosophy with Stripe-headed Tanager, now various types of Spindalis), except for complications with a few Mexican species currently in Piranga.

YES. Although typically conservative on “improving” English names, in this case, the cost in terms of instability (a name that has been used for a century or more) is outweighed by the benefits of the change, namely (1) continuing to call it a warbler conceals the important phylogenetic finding, now decades old, that this is not a member of the Parulidae or any other family with “warblers” in it, and (2) it isn’t “olive”. So, neither part of its current name is accurate but instead, misleading. I like the suggested “Ocotero” — it emphasizes the distinctiveness of the bird with a one word name (as also with Wrenthrush, Sapayoa, Palmchat) that doesn’t fit into any other family I also personally like the use of a Spanish name in this case for a bird that barely makes it into the USA — it adds some spice. In my opinion, this falls within the realm of C4 in our Guidelines: “Such changes are evaluated on a case-by-case basis, with assessment of the cost of loss of stability versus the benefit of increasing phylogenetic information in the name”.  My subjective evaluation of the cost-benefit ratio in this case favors the change.  Many people don’t actually realize that this isn’t a warbler, despite removal from Parulidae being decades old.  Unlike, say, Scarlet Tanager, this is not a “core” member of the North American avifauna — it barely leaks across the border — and so the number of times “Olive Warbler” appears in the literature is likely minute compared to Scarlet Tanager.  By the way, kudos to the proposal author — this is an exceptionally well-written, well-reasoned proposal.

YES. The proposal lays out a good rationale for changing the English name of this species, and Ocotero seems like a fitting name because it is already used though much of the species’ range and reflects its association with pine habitat. Nice proposal.

YES. I initially was inclined to vote NO in favor of taxonomic stability and acknowledging that such misnomers are rampant among common names. However, this is a good opportunity to unify a common name with increased knowledge of a given species. Both ‘olive’ and ‘warbler’ are misinformative, while a widespread, memorable common name exists throughout much of its range that highlights Peucedramidae’s monotypy and habitat affiliations. Changes to common names should be done judiciously, but this seems a good one to me. That said, I acknowledge that a YES vote somewhat contradicts our recently established guidelines.

NO. The proposal makes an excellent argument, and I really like the proposed name and want to vote yes. However, NACC policy on common names does not allow for this type of change. Our policy specifically states that “English group names do not have phylogenetic significance even at the family level (e.g. flycatcher, warbler, finch, tanager, grosbeak, and bunting) and are best treated as morphotypes.” This is why the names of North American “tanagers” in the genus Piranga (e.e, Summer, Scarlet, Hepatic, Western Tanager) were not changed even though these birds are in Cardinalidae, not Thraupidae. As much as I might want to vote Yes, to remain in compliance with the policy, I think this has to be a No vote.

NO. This proposed change seems to me to fall squarely under the English name policies we re-derived and posted just this past month. I see no compelling reason to replace this long-established English name with any alternative. I’ll point out that birds with ‘warbler’ in their name fall within at least a dozen different families worldwide, so that term is like ‘finch’ in its taxonomic generality.

NO. I think our rewritten policy on English names covers this kind of case pretty well, and we should not change this long established name. In a perfect world, such monotypic taxa perhaps “deserve” unique names, but though “Olive Warbler” may misrepresent the bird’s phylogenetic position and plumage, the name also gives historical and phenotypic information (it does seem like a “warbler”) to the user. I am not sure how widespread the use of Ocotero is, or if it is the only Spanish name. If the Committee could ever get a consensus among Spanish speakers in our area to standardize Spanish names, this would be a great name for that list.

NO. The proposal makes a pretty strong case for changing the name of Olive Warbler. However, judging from Google searches, Ocotero by itself hardly seems to be the established Spanish name for this species—Ocotero enmascarado is, or Chipe ocotero, or Chipe olivaceo. And the proposal does not cite any sources for the statement that Ocotero is commonly used in Mexico and N C America, though HBW Alive does list Ocotero as the sole Spanish name. If we do change it, I would prefer something more informative than simply Ocotero (yes, it does occur in pines, but this name tells us nothing more than that). Perhaps Masked Ocotero? Is there really no previously used English common name that would be more suitable and less disruptive?

NO. Although the proposal is well written, thoughtful, and indeed likeable, the first two sentences properly set the broader framework: For stability alone, we should not start changing English names to help make them more taxonomically informative. I would vote yes for Ocotero to be the Spanish name, however.

NO. We have known that Olive Warbler is not a wood warbler for a long time. NACC officially moved it into a monotypic family over twenty years ago. It is hard for me to think that at this late date, changing the long used name, and as far as I know its only English name, provides any benefit.

2020-A-2: Change the generic classification of the Trochilini (part 1)

YES to all recommendations – 5 without comments.

YES to all of the recommendations. This is a complex situation, and the authors did a great job of laying out the different possible treatments and their rationale for favoring one option over another.

YES to all of the recommendations. For 6, although I like the idea of reducing the number of monotypic genera and lumping them, the proposal lays out a good argument for retaining them. Plus, retaining these genera would increase stability in this group, which is already going through a lot of changes.

YES to all of the recommendations. In general, given the number of genera in the Trochilidae, some amalgamation of genera may be preferable, but I don’t think we should be lumping genera together that are phenotypically quite different.

YES. For both of these motions I do not know many (most?) of the taxa, but these motions seem reasonable and well-constructed.

YES to all of the recommendations. 1 – Option B, especially considering that Phaeoptila was once a monotypic genus in the past, I agree with this measure to recognize its placement in the phylogeny and phenotypic distinctiveness. 2 – Option B. Taxonomy should be congruent with phylogenetic relationships. Polyphyletic taxa should be avoided. 3 – Option B. Taxonomy should be congruent with phylogenetic relationships. Polyphyletic taxa should be avoided. 4 – Option B. Taxonomy should be congruent with phylogenetic relationships. Polyphyletic taxa should be avoided. 5 – Option A. Seems a good way to resolve polyphyly in Campylopterus without creating new genera. Clade B4 makes sense phenotypically + biogeographically. 6 – Weak YES to option A. I don’t like having a clade consisting of completely monotypic genera but I’m not sure I see a better solution. They are all quite phenotypically distinct and all but Klais have quite small geographic ranges. This preserves taxonomic stability. NO to option B because they’re all so different I feel lumping them together doesn’t make sense. Although this revised hummingbird phylogeny will have a lot of generic groupings that are phenotypically diverse. Weak NO to option C. This could be a good solution, but the problem with this option for me is with uniting Orthorhynchus, Stephanoxis, and Anthocephala. While Orthorhynchus and Stephanoxis are both crested, Anthocephala is not and each one has a very small restricted range with no biogeographic affinities to the others. Klais and Abeillia both occur in central America, but overall they’re all very distinct. I don’t see an easy, obvious solution here. 7 – Option B. No to Option A because I tend to only favor monotypic genera when there is pronounced phenotypic differentiation or nothing obvious to unite them. 8 – Option B. As stated in the proposal, these two genera are actually similar. Seven species doesn’t seem overly large given their similarities. 9 – Option B to retain monophyly; new phylogenetic info reveals similarities.

MIXED. (1) Option A (assuming that sensu lato means that it includes Cyanophaia). This obviates a vote on 2 and 3. (This is the only full-group option among the four groups.). (4B) As noted above, I’d prefer Orthorhynchus for them all. But given the options I’d have to vote yes for 4B. (5) Option A – more conservative, with fewer genera. (6) Option B – lump these monotypic genera into Orthorhynchus and consider these all subgenera. (7) Option B – lump. (8) Option B – again, lump. (9) Option B – more conservative, with fewer genera. (10) Option B – again, lump.

Since reading McGuire et al. 2014 I could see we were headed into a necessary but messy revision of historic alignments. Great work on tackling this mess, as it currently stands. I am not sure the proposed solutions are going to resolve things well, though. First, McGuire et al. (2014) included just six genes (two mitochondrial and four nuclear), and in a group with rapid speciation I think we’ll only gain confidence in relationships at these shallower levels with more markers able to accurately track historic patterns of divergence. So my bet is that we will eventually see some of these relationships change (probably especially in Group D). However, this is a good dataset that greatly improves our understanding of reality. Secondly, though: One of the hurdles in making a phenotypically based taxonomy fit a genetic phylogeny well is to find phenotypically diagnosable characteristics that match genetic clades. Stiles et al. (2017b: 402) bring in biogeographic criteria for this, which is not in my experience widely done. More importantly, though, they also try to keep genera roughly in a framework of clade age, not easy to do when phenotype shows such variable rates of change. My biggest concern here is that branch lengths and clade depths are internally determined, i.e., relative only to this group and these genes. On top of this, it is a group with rapid phenotypic change, lending itself well to oversplitting at the genus level relative to many other avian genera. I think we see this fairly well here. 

The Trochilidae have long been thought to be oversplit at the generic level relative to other groups of birds, and I had hoped to see more conservatism here to help rein that back in. Here I think the work done in Stiles et al. (2017a, b) is excellent and very compelling – but I would have preferred to change the focus to include other avian groups and here make heavy use of subgenera. In Stiles et al. (2017b), subgenera seem to only be used when referring to historic treatments. By my quick count of Stiles et al. (2017b, fig. 1), in this proposal and the next what were 33 genera are proposed to be 36 – and fully 13 of these are monotypic. If instead we were to recognize that this group has exhibited fairly rapid phenotypic evolution and used clade age not just as an internal metric but in reference to avian genera more broadly, with, say, Turdus as an example genus outside this group (ca. 7.5 Ma; Voelker et al. 2008 Global Ecology & Biogeography 18: 44), this group would be roughly 9 genera. If we instead used generic clade ages in our recently (2017) revised view of Anas and the genera that used to be part of it, then clade ages of 9.4 – ~11.2 Ma are appropriate, leading here (from McGuire et al. 2017, fig. 1) to ~3-6 genera. In the Trochilini, groups A-D would seem to correspond really well with this, albeit with more rapid phenotypic diversification than in those ducks.

 “What exactly is a genus?” is a hard question (and here I guess I’d focus on “What is an avian genus?”). And after species limits, it’s at the generic level where we’re most likely to experience frictions between morphology, and its uneven (among lineages) responses to selection, and time, with its steady, neutral accumulation (in the genetic characters we use to measure it). At the species level I think we agree it’s critical that phenotypic data should greatly outweigh time in determining limits. How much should this change at the generic level? Somewhat, surely, though we do want to retain, I think, morphological correlates. We’re not going to have an answer to what a genus is soon, but in this group in particular I think more conservatism is warranted than where these proposals lead. If there was an option to vote for each group as a genus, for now I’d choose that and treat each proposed group here as a subgenus (I don’t know these birds well enough to propose morphological correlates, but I suppose such could be discovered). That would give (if I read Stiles et al. 2017 Appendices 1 and 2 correctly) four genera, A = Cynanthus, B = Orthorhynchus, C = Thalurania, and D = Trochilus, and 36 subgenera. I predict that when Aves achieves relative taxonomic stability once we’ve sequenced and completed analyses on most or all extant species and worked to achieve consistency among avian taxa, this solution will be closer to what it becomes than the one proposed – unless we decide that genera, like species, should be defined primarily on phenotype (and I don’t see us going back that way). Meanwhile, there is a lot of work to do, and we’ll likely get a few more things wrong along the way. Okay. That’s a long and boring preamble to explain why, given that my first choice is not among the voting possibilities, I am going through and voting for the most conservative options.

2020-A-3: Change the generic classification of the Trochilini (part 2)

YES to all of the recommendations – 5 without comments.

YES except for subproposal 3. For that case, I would be inclined to retain monotypic genera for the 3 species here, Aphantochroa, Eupetomena, and Taphrospilus.

YES to all of the recommendations. This brings NACC into agreement with SACC, which has already voted to accept these changes.

YES to all of the recommendations. This is a complex situation, and the authors did a great job of laying out the different possible treatments and their rationale for favoring one option over another.

YES. For both of these motions I do not know many (most?) of the taxa, but these motions seem reasonable and well-constructed.

YES to all of the recommendations. For 1B, This grouping sits better with me than group B3 in the prior proposal, but I still feel monotypic genera should be rare. For 2B, taxonomy should be congruent with phylogenetic relationships. Polyphyletic taxa should be avoided. For 10B, I might even consider expanding this to include Amazilis and Uranomitra. For 11A, If we are to recognize Chionomesa, we need Leucochloris. For 16B, this is better than multiple monotypic genera.

MIXED. Same preamble as 2020-A-02 above, though here an argument could be made for 3 genera. My votes here are: (1) Option A – one genus. (2) Why is there not an Option C, putting all three of these into Eupetomena? That’s what I’d vote for. (3) Option C – one genus. (4) No. There are just far too many monotypic genera in this group. I’d go for this group as Trochilus with 13 subgenera. If we’re going to use genetic distinctiveness as a central criterion (as given here for Talaphorus and above for Klais – Anthocephala), then that criterion *has* to be based on a broader survey of Aves so genera have a more even meaning among birds. (5) Yes, there is an alternative – a genus Trochilus for all clades from Talaphorus to Chlorestes in Group D. This would be genetically pretty comparable to Turdus and Anas. (6) Option B – single genus. (7) Option B – given notes above I disagree that it “would subsume too much genetic divergence.” This is only true relative to the total focus on Trochilini and is not sustained more broadly in Aves. (8) Option B – fewer genera. (9) Option B – fewer genera. (10) Option B – fewer genera. (11) Option B – fewer genera. (12) Option B – fewer genera. (13) Option B – fewer genera. (14) Option B – fewer genera. (15) No – the feasible alternative is noted above in 5. (16) Option B – fewer genera. (17) As 5 and 15.

2020-A-4: Split Garnet-throated Hummingbird Lamprolaima rhami

NO. For the reasons stated in the proposal.

NO, owing to low levels of divergence in mtDNA and issues raised in the comments of other members.

NO. These two very similar taxa appear to be the product of fairly recent divergence and I think are best treated as subspecies.

NO (for now). The genetic data clearly show a split between populations west and east of the Isthmus of Tehuantepec, but that split is relatively recent and one taxon was not sampled (presumably it would align with the eastern populations but that needs to be shown). The morphological data are not informative of species-level status. What are the subspecies based on? Are there any plumage differences, or differences in vocalization or other behaviors? I agree that these are better treated as subspecies for now, pending additional information that might shed light on their taxonomic status.

NO. The current taxonomy might not be valid, even at sspp. level, but agree that for BSC more information is needed, and as noted saturatior, not sampled.

NO. Clearly differentiated, but I agree with the proposal that these are best treated as subspecies with a relatively recent split and limited phenotypic differences.

NO. These taxa are better treated as subspecies barring further data more informative about species limits under the BSC.

NO. In addition to the arguments provided in the proposal, I would also like to see data from the third subspecies to see how that fits into the story (possibly sister to L. r. rhami, but not necessarily so).

NO. The two clades are clearly deeply divergent in their mtDNA and BPP supports two species. Thus, populations on either side of the isthmus have been separated for some time. Clearly, they would be separate species under a concept such as the phylogenetic species concept. However, the NACC follows the biological species concept and there is no evidence that birds in the two areas would be reproductively isolated if they came back into contact. Morphological differences are relatively minor and no information on breeding or courtship characters is provided. Any courtship behavior differences? Vocal or other sound-based differences?

NO. I agree with the proposal that the paper does not address the most important question in assessing species level decisions under the BSC: are the taxa reproductively isolated? Currently, the populations are isolated in time and space, but the rather small mensural differences and near lack of plumage differences argue rather strongly that the populations would freely interbreed if in contact.

NO, as per the proposal recommendation. Because these taxa are allopatric, the only surprising finding would be that did NOT differ genetically to some extent. Minor mensural differences are also expected given this distribution, but that they are significantly different statistically is irrelevant to taxonomy for any species concept that incorporates morphological data, much less the BSC. Furthermore, the characters that showed statistically significant differences (bill length and wing length) are notoriously labile and seldom mark species differences; in fact, these measurements often differ between the sexes within a hummingbird species. It remains unresolved whether the plumage characters on which the taxon names are based are diagnostic. Binford (1969, Oaxaca monograph) disputed the validity of occidentalis Phillips 1966, but did not have access to specimens from the type region. Schuchmann (HBW) disputed the validity of occidentalis and also saturatior Griscom 1932; however, no actual analysis was presented. Nonetheless, there seems to be as much evidence to support treating them as a single monotypic species as there is for treating recognizing more than one species. A productive project would be to determine whether the three named populations are diagnosable based on plumage. In fact, one wonders why plumage differences were not also recorded in the present study as long as the 208 specimens were measured for bill length, etc., given that the subspecies were described on the basis of color differences, and that if these color differences are diagnostic, they presumably have a genetic basis.

2020-A-5: Recognize Amazilia alfaroana as a species not of hybrid origin, thus moving it from Appendix 2 to the main list

YES. I cannot see how this can be a hybrid, nor does it so closely resemble the highly disjunct A. cyanifrons that treatment as a subspecies seems warranted. I have also examined the holotype at NHM-UK and compared it with series of cyanifrons and hoffmanni, and agree with Kirwan and Collar regarding its distinctiveness. Unfortunately, both the photographs in the Zootaxa article (at least as displayed on my screen) and the illustrations in HBW Alive seem somewhat unhelpful, however, and I recall being quite convinced by actually viewing the specimen in comparison with the other taxa.

It is unclear to me why we should not recognize this as a full species, given the implausibility of any other explanation. It may be extinct, but that has no relevance to species status. Being an aberrant individual of hoffmanni hardly seems likely since aberrance does not usually affect multiple seemingly independent characters. The type of alfaroana is a well-made, well-preserved specimen with its main features preserved symmetrically, so they aren’t difficult to observe and don’t require interpretation or guesswork.

If this is/was a montane forest species, there is indeed extensive habitat on Miravalles. There are few hummingbirds in this area, probably explaining why the tourist lodge I stayed at there did not have hummingbird feeders up. At least along the main road up the mountain, much of the forest belongs to the geothermal company and so is of restricted access. Although I would have thought that with all the birding activity in Costa Rica, there would have been targeted searches for this bird, at least after the Zootaxa article appeared in 2016, perhaps it is difficult to gain access to the forest, not to mention that this is otherwise not one of the most ornithologically compelling parts of Costa Rica.

Of course it would be ideal to get alfaroana sequenced and sorted (and rediscovered!), but in my view it doesn’t belong in the Appendix, as no explanation other than species status is convincing.

NO. For the reasons stated in the proposal.

NO. I agree with the proposal that genetic data (from a toe pad sampled from the single specimen) are needed to shed light on this situation.

NO. Odd hybrids are common in hummingbirds and that remains a likely explanation for this specimen. This could be tested further with genetic methods.

NO. I think the proposal lays out good arguments for retaining this taxon in Appendix 2 for the time being. Further, while the specimen in question does differ from either of the two putative parental taxa, there are plenty of instances where the hybrid displays traits that are not found in either parental taxa. Genetic data would go a long way in resolving this interesting case.

NO. I lean toward accepting this as a valid taxon, except that we could still learn more if we could squeeze some genetic data out of the specimen. I think Kirwan and Collar did a good job of building the case to treat it as a valid species, but given the weird hybridizations possible among hummingbirds, and that there was no causation for a population to go extinct at that time and place, I think it is better to wait for genetic data.

NO. Although the characters may not seem “intermediate” between presumed parental species, some of these characters could be transgressive. I would prefer to wait until we have some genetic data.

NO. It is hard to accept the scenario that a separate species existed from this area when the habitat is largely unchanged. I realize the current assignment may be troubling, but establishing a new species based on the available evidence is even more disturbing. I counter with the case of Brace’s Emerald (Chlorostibon bracei) from tiny New Providence, Bahamas, where early settlement combined with say a powerful hurricane might have wiped it out before comprehensive ornithological exploration. The Cuban Emerald (C. ricordii), present in the northern Bahamas (and Cuba) is absent from New Providence.

NO. It might be a distinct species, but I don’t think the current data demonstrate that. I agree with the proposal that it is best to await its rediscovery or genetic analysis of the type that establish it as a distinct lineage.

NO. Despite the new evidence, this remains a one-off and thus more likely to be of hybrid origin. We should not expect hybrids to have intermediate phenotypes. Genetic data would help resolve this.

NO, as per the proposal recommendation. With N=1 in terms of specimens, extreme caution is required in my opinion. Although the data presented suggest that it cannot be a hybrid, I also would prefer some genetic data, although given the poor DNA likely available from the 1895 type, the controversy may not be resolvable by DNA either (e.g. the ongoing controversy over Heliangelus zusii). In South American, more than 60 (!) “species” of hummingbirds have been described that are currently considered hybrids or aberrant individuals. This family is exceptionally prone to oddball hybrids and odd plumages

2020-A-6: Change the linear sequence of species in the genus Dendrortyx

YES. 6 without comment.

YES. Seems straightforward.

YES. This change in linear sequence is needed given the available data.

YES. Genetic analyses and our rules of sequencing argue for the change.

YES. Simple change to linear sequence to reflect new phylogenetic information.

YES. Required book-keeping based on solid genetic data.

2020-A-7a: Make two changes concerning Starnoenas cyanocephala: Assign it to the new monotypic subfamily Starnoenadinae

NO. Genetic and phylogenetic data needed to make this major change.

NO, for reasons given in the proposal, namely the lack of genetic data on relationships between S. cyanocephala and other columbids.

NO. In the absence of phylogenetic data, it remains very possible that this is an intriguing example of convergence in morphology and behavior.

NO. Excellent proposal. A couple decades ago I would have probably voted yes to both of these; the morphological evidence does suggest subfamily level divergence. However, we do have excellent molecular tools now that can resolve this, and I think it would be premature to make this change given genomic efforts now under way.

NO. Very similar to the case for Amazilia alfaroana, where it seems best to wait for genetic data to bolster the case that Starnoenas is quite different. The data in Olsen and Wiley is very solid, but the overall picture would be clearer on how to draw subfamily boundaries with a molecular phylogeny that includes Starnoenas.

NO. I appreciate the structural differences described, and there are certainly behavioral differences I see (from nine visits) that differ from the Geotrygon I know, including the three resident species from Cuba. But, isn’t having them in a separate genus adequate for now? This is an advancement from continuing to maintain Wilson’s Phalarope within Phalaropus. As for the English name change, I see no compelling reason to make this change.

NO, given the lack of genetic evidence and the lack of subfamilies in the Columbidae. Clearly though, this anomalous bird can only be very distantly related to the quail-doves, so it would seem better to simply remove the “quail-“ from the group name (although this could invite confusion with Blue-headed Wood Dove Turtur brehmeri, but this seems a minor issue). Nevertheless, I would not advocate creation of a new group name (Partridge-dove) for this monotypic species.

NO. While compelling, I would not feel comfortable making such a major change without first considering genetic data, given the oddness of the relationship suggested. We have seen several strange phylogeographic patterns emerge similar to this, including the sister relationship between Eurypygidae and Rhynochetidae, as well as between Sapayoa and the Old World Broadbills, but without genetic data, I am unwilling to make the final leap on Starnoenas. Further, I would be in favor of adopting subfamilies for Columbidae.

NO. Well written and comprehensive proposal. The evidence provided does not definitively demonstrate its phylogenetic placement. I don’t feel comfortable placing it in a monotypic subfamily until this point, especially since no subfamilies are currently recognized by NACC.

NO to formal recognition as a subfamily until supported by genetic data. I really look forward to seeing how this turns out. The fascinating phenotypic similarities seem beyond explanation by convergent evolution, but especially given the biogeographic unlikelihood, I see no harm in waiting for an independent data-set.

NO. Starnoenas is a distinctive bird and stands out among the quail-doves. It may very well not be particularly close to them. However, I don’t think Olson and Wiley really demonstrate where Starnoenas’s affinities lie. In the absence of any other subfamilies in Columbidae, I don’t think placement of Starnoenas in a separate subfamily is justified. Clearly additional work on this species is in order.

2020-A-7b: Make two changes concerning Starnoenas cyanocephala: Change the English name to Blue-headed Partridge-Dove

YES in view of this species’ distinctiveness. It would be a relatively painless way to call attention to the uniqueness of the species and that it is not just another Quail-Dove, regardless of whether it is actually more closely related to Australian taxa.  This would increase the information content of the name with minimal cost to stability.

YES. Although we don’t know for sure where Starnoenas goes in the phylogenetic tree, it seems clear that it is outside the true Quail-Doves. This name change would emphasize that fact, and seems like a reasonable English name for this distinctive species. If we conclude that Starnoenas is not sister to the Quail-Doves, we will need to make this change anyway, or drop hyphen in Quail-Dove.

NO. 4 without comment.

NO. Genetic and phylogenetic data needed.

NO. I prefer Blue-headed Dove (not an option in this proposal).

NO. This is another name ‘improvement’ scenario. It seems especially non-warranted in the absence of stronger evidence about part a.

NO, for the same reasons for voting NO on Part A. While it is clearly not like any of the other quail-doves in many characters, the relationship with Australasian doves has not been made clearly enough to warrant changing the name at this time.

NO. For similar reasons as stated above, I see no reason to change the common name until phylogenetic affinities are ironed out (DNA sequencing + molecular phylogenetics).

2020-A-8: Recognize Mexican Duck Anas diazi as a species

YES, for the reasons outlined in the proposal.

YES. No major new evidence here, but the case before was compelling. I’m not sure I understand the reasoning here for maintaining the status quo. It was lumped in 1983 (AOU 6th) based on evidence we would likely not accept now, and when the sister species weren’t included in the lump. Now with more evidence there is no compelling reason why Hawaiian Duck, Mottled Duck (both sspp., apparently genetically somewhat different) and American Black Duck shouldn’t be lumped too. The alternative is to re-split Mexican. It is interesting that they hybridize to some degree in south Texas, but with Mottled Duck. I simply don’t see “wild” Mallards in summer in the Southwest and east along the Mexican border. Thus they have self-sorted to a large degree. Folks working in Arizona do see intergrades as one can see between American Black Ducks and Mallards in northeast North America.

YES. Based on new evidence, there is clear separation between Mexican Duck and Mallard. Even though the contact zone was not sampled, if gene flow was extensive in that region, the admixture analyses would likely have shown this. To be consistent with how we treat other species in this group, I think it’s best to split Mexican Duck at this point.

YES, the new data strengthen the conclusion that, if Mottled Duck and Black Duck are considered full species, Mexican Duck also should be treated thus (as already treated by Clements and IOC).

YES. This situation is in the zone where either outcome seems reasonable based on the available information. The kicker for me is that other taxa in this group with equivalent or lesser evidence for distinctiveness are recognized as species. To treat them all equivalently, we must do the same here.

YES, with some reservations. Reading back through comments on 2018-C-10 proposal and trying to understand the genetics of the current situation, I think it is best to consider diazi as a separate species. However, it is a bit unsettling that the Lavretsky et al. (2019) paper does not sample populations near the contact zone. The clear differentiation of diazi in this study could result from geographic distance, a short time since contact, and a lack of Mallards in the southern part of the distribution of diazi. AMBD and MODU now have Mallards within nearly their entire distributions (especially in winter when pairs form), but looking at eBird, the part of distribution of diazi in Mexico largely lacks Mallards (a bit less so in winter). AMBD and MODU lack that sort of refuge, and thus are not as well differentiated genetically from Mallard.

YES. I vote for this change based largely on the previous proposal to split Mexican Duck. The new genetic evidence is consistent with species status for Mexican Duck. The current proposal adds evidence, but by itself is not sufficient. However, given the detailed discussion in Proposal 2018-C-10 in addition to these data, I think Mexican Duck should be split. The evidence for splitting it seems at least as strong as that for Mottled Duck, and perhaps stronger than Black Duck.

YES. I presented lengthy arguments in favor of this split last year — perhaps the most extensive set of comments I have ever submitted. Burden-of-proof, in my opinion, is on treating this as a subspecies. There is no evidence for random mating or free gene flow between these taxa.

NO. I agree that the addition of ddRAD data provides a stronger case for possibly splitting these taxa, but I am still bothered by the sampling scheme. As noted, there are no samples from areas where the taxa meet or even where they approach outside of the contact zone (the closest samples for Mallard and Mexican Duck are hundreds of miles apart). I think this gap in sampling needs to be filled before making a definitive split of these taxa.

NO. This is indeed a difficult case, right in the gray zone. Genomic diagnosability is playing a very large role here (and that alone does not define species, as we know), and purposely not sampling in a contact zone causes me to be skeptical and ask for real estimates of levels of gene flow. “not extensively admixed” likely describes many subspecies with local adaptations despite gene flow. I don’t think we have this system adequately bounded yet; we know gene flow is nonzero, and we know it is not rampant. The maintenance of geographically partitioned adaptation in the face of gene flow is practically our definition of subspecies (between which gene flow occurs).

NO. I disagree with the recommendation of the authors to recognize Mexican Duck (Anas diazi) as a separate species. The lack of samples from the contact zone between A. diazi x A. platyrhynchos and A. diazi x A. fulvigula makes me question assertions that “contemporary gene flow and introgression” may be lower than assumed. Given the proclivity of ducks in the mallard complex to readily hybridize, I feel the burden of proof still lies on demonstrating that these taxa do not exhibit rampant admixture / backcrossing in their contact zones. The TreeMix analyses were based on outlier loci, which by definition already differ in allele frequency substantially among the taxa considered. I don’t think that these analyses demonstrably indicate reduced gene flow. In fact, the authors also state:

“For all SNPs and nonoutlier SNPs, gene flow was inferred for several pairs of taxa, including gene flow from Mexican ducks into WGC mottled ducks, from black ducks into mottled ducks, and from mallards into either black ducks (SNPs from autosomal nonoutlier loci), or Mexican ducks (all Z‐linked SNPs) (Figure 7; Table S3). In addition, gene flow from WGC mottled ducks into mallards was inferred when analyzing SNPs from Z‐linked nonoutlier loci only.”

Furthermore, genetic diagnosablility—as illustrated by the Structure plots—does not equate to species status in my mind. It is indicative of population structure, but does not translate to independent evolutionary lineages that are reproductively isolated. I feel that intensive studies of genetic admixture and assortative mating in contact zones between the northern range of A. diazi x A. platyrhynchos x A. fulvigula are needed where they occur side by side.

The lack of sampling of phenotypically intermediate individuals and other individuals from the contact zone combined with some of their analyses indicating substantive gene flow make me vote NO to not split. However, I do think that if the NACC continues to recognize A. rubipes, then recognizing A. diazi as a separate species makes sense for the sake of taxonomic consistency.

2020-A-9: Split Royal Tern Thalasseus maximus into two species

YES. 1 without comment.

YES. This change is necessitated by the molecular data.

YES. African Crested Tern seems like a good English name and contributes a certain symmetry to Chinese Crested Tern for T. bernsteini.

YES. Huge geographic separation making any potential interbreeding very unlikely. This, coupled with clear phylogenetic and genetic separation imply these two forms are biological species. I think our policy is to not retain a common name if there is a split. Therefore, the name “Royal Tern” may need to be replaced.

YES. Parallel results from independent molecular data sets. Reasonably high divergence. Non-sister-taxa relationship.

YES. With confirmation of non-sister relationships in nuclear and mitochondrial DNA in a group with very similar morphologies, I agree that this evidence supports a species-level split. I also agree with the English name part of the proposal.

YES. Although I voted not to separate Cabot’s and Sandwich Tern, I think this case is a bit different, with a much larger geographic barrier to gene flow, a closer relationship with one of the group with another species, and at least some morphological differentiation. Thalasseus terns present problems in classification.

YES. Thalasseus maximus is polyphyletic as currently defined. Splitting T. m. maximus and treating T. m. albididorsalis as an “allospecies” resolves this problem. These putative taxa exhibit phenotypic and biogeographic differences as well.

YES. Despite the very similar phenotype, the genetic evidence convinces me that splitting these makes sense. I would go for African Crested Tern, unless there is a strong consensus in the Old World for something else.

YES. After reading the proposal, I was left with two concerns. (1) why not lump all three, or at least albididorsalis with bengalensis? (2) Is it not relevant to consider the austral S American population of maximus here, which is mentioned as being more similar morphologically to albididorsalis but then not discussed further in the proposal?

Collinson et al. however address both issues: (1) “… multiple diagnostic positions in several nuclear loci separate albididorsalis from bengalensis, demonstrating reduced, if any, nuclear gene flow…” This, coupled with the close genetic relationship of all sampled populations of bengalensis to each other, makes me prefer to split albididorsalis; and (2) the austral S American population was in fact sequenced and is genetically intermingled with North American samples.

ABSTAIN for now. The genetic data are weak by current standards: mtDNA only and N=2, 3, and 3 for the critical taxa. I would like someone with some expertise to explain why this isn’t just a gene tree or why it is sufficient to be accepted as a species tree.

2020-A-10: Recognize Great White Heron Ardea occidentalis as a species

YES. 1 without comment.

YES. The high degree of assortative mating is convincing evidence that this taxon should be treated as a species separate from Great Blue Heron.

YES. McGuire et al. (2019) demonstrate that occidentalis and herodias are largely segregated geographically and ecologically, with differing but overlapping breeding seasons, and (not surprisingly) significantly non-random mating.

YES. As has been hashed out in Van and Kevin’s discussion, this one comes down to where you draw the lines about gene flow and mate choice. We certainly live with species level taxa having lots of gene flow (Glaucous-winged and Western gulls especially) and I have long felt that assortative mating within contact zones was a benchmark for species status. GWHE and GBHE have been in contact in Florida Bay for centuries and yet they still by and large mate assortatively, but with frequent hybridization.

YES. Another victim of the big lump of January 1973. I know the situation well in south Florida, but on trips for over a decade, I regularly see Great White Herons on the northern cays off northern Cuba. I see Great Blue Herons there too, including small flocks of passing presumed migrants. In more than a dozen years of trips, I have yet to see an intergrade. Yet, inland in Cuba, I see only dark Great Blue Herons, and they breed in Cuba. Whatever the complications they seem to have separated themselves into separate species.

YES. It seems like evidence shows that while there is some interbreeding, it is by no means free interbreeding. This change dates back to the 1973 supplement where many species were lumped that have since been split. The current data suggest a situation more similar to Lazuli/Indigo Bunting or Rose-breasted/Black-headed Grosbeak rather than Red- and Yellow-shafted Flickers.

NO. Although there is assortative mating, the structure plot shows extensive admixture indicating that a significant amount of gene flow occurs.

NO. The gene flow seems quite substantial here and genetic differentiation is very, very low (Fst between blue and white morphs in FB is 0.007). I recognize that there is evidence for positive assortative mating (like with like), but its similarity of Q scores of blue and white birds from the Florida Bay is quite striking, suggesting substantial backcrossing / introgression. Given that white plumage may have a oligogenic basis with fairly simple genetic architecture (although apparently not single-gene Mendelian according to McGuire discussion?), assortative mating based on plumage color may really only be tracking a small portion of the genome and other things like spatial / temporal variation in mate choice and extrapair copulations could also be at play. A tough decision to be sure, but to me, these do not seem like independent evolutionary lineages.

NO. 15% disassortative mating and enough phenotypic evidence of hybridization to have a species (inappropriately) named for those specimens indicates levels of gene flow that are too high for good biological species. The presence of assortative mating in this case is not sufficient to limit gene flow enough for full species status, in my view. This fits exactly our concept of subspecies – locally adapted populations maintained in the presence of substantial levels of gene flow. An absence of free interbreeding suggests divergent selection is operating to maintain local adaptation; at these levels of gene flow these two taxa remain evolutionarily tied together, and not on independent trajectories (only adaptive alleles seem to be). We could look at it as incomplete speciation or an evolutionarily stable balance between selection and gene flow.

NO. This was a challenging decision, but ultimately felt that there were still a lot of unknowns from the system. In particular, I want to know more about the distribution of actual intermediate phenotypes within the Florida Bay to better understand the proportion of hybrids to phenotypically pure looking Great Blue Herons. Further, knowing how well phenotype matched genotype would be important in this system, since mate preference was assessed based on phenotype assessments. I think this could be particularly problematic since in the STRUCTURE plot shown, there appear to be birds that derive most of their ancestry from Great Blue Herons but are phenotypically Great White Heron, and vice versa. Overall, though, I think this is an intriguing situation, and I could easily see supporting the splitting of Great White Heron in the future with additional data.

NO. In my opinion ‘reproductive isolation’ means much more than behavioral mate choice. There is extensive ongoing admixture between these forms. The case for species status here seems less strong than others for which the vote has been against splitting (e.g., the taxa in the yellow-rumped warbler complex).

2020-A-11: Change the English name of Checker-throated Antwren Epinecrophylla fulviventris to Checker-throated Stipplethroat

YES. 1 without comment.

YES. No reason not to follow SACC.

YES. I am perfectly happy to follow the SACC on this.

YES. There is no reason to differ from the SACC on this, and the new name is a good one for reasons given in the proposal.

YES. Makes sense to follow SACC in general when the geographic jurisdiction is primarily in South America, and especially in this case.

YES. This fits squarely under Section C.4 of our Guidelines on English Names.

YES, to make our classification consistent with SACC.

YES. We should follow the SACC on this one, and I agree that Stipplethroat is a good name for this ecologically neat little group of thamnophilids.

YES. But only because this is a primarily SA group and the SACC has already approved this name change. Were it only up to us I would vote no, to keep the stability intact.

YES. I’m not a fan of the group name Stipplethroat but it’s already a done deal with SACC and it makes sense to follow SACC for the single species in the NACC area.

YES. This brings us into congruence with SACC. SACC went to this change to Stipplethroat because of a complicated English name and taxonomic situation with another member of the genus. I argued for adopting Stipplethroat for the entire genus, and I remain convinced that is the way to go. It would make no sense for us to maintain Antwren for part of the range of one member of a fairly large genus that otherwise is South American.

2020-A-12: Modify the linear sequence of species in the Phalacrocoracidae

YES. 3 without comment.

YES. Required book-keeping based on solid genetic data.

YES. Reasons for this modification are laid out in the proposal.

YES. Sensible modification to linear arrangement based on robust phylogeny.

YES. The linear order makes sense. I do favor some splitting of the genera, although not inclined to go fullbore into 7 genera, as suggested by Kennedy and Spencer.

YES to adopting changes to the linear sequence of cormorants. At this time, I do not support splitting the family into 7 different genera

YES. The new data on relationships in the family necessitates changes to our sequence.

YES. I think a proposal to consider adopting multiple genera within Phalacrocorax would be important.

YES. Multilocus molecular dataset supports a rearrangement, and this works fine. Aside: I would probably not support dividing Phalacrocorax into seven genera. If we are going to begin dividing higher taxa up strictly by clade age, that needs to be a broader discussion in ornithology. While I find the idea attractive, I would not like to overthrow a system based on phenotype, and I haven’t yet seen anything other than seat-of-the-pants amalgamations so far (if I’ve missed something on this, please point it out – I would enjoy reading it). I think I’ve noted we are not very good at this yet across Aves. But also consider that the insect genus Timema (walking sticks) encompasses about 30 million years of evolution, equivalent to many avian orders.

2020-A-13: Modify various linear sequences to reflect new phylogenetic data

YES to all – 4 without comment.

YES. These all look good.

YES to all. Required book-keeping based on solid genetic data.

YES to all. I appreciate the time it took to compile all these together.

YES to all. Bookkeeping changes that are consistent with the available data and the SACC.

YES to all. I learn new things where least expected. That taxa with fewer species precede their sisters is I think something I never knew. And some say that taxonomy is boring.

YES to all. Linear classifications are much more useful when they accurately reflect phylogeny, species richness, and NW -> SE distributions.

YES to all but (e) and NO to that part of the motion. The genetic evidence is not strongly supported between Chloroceryle inda and C. americana. Van knows this genus much better than I, but the new arrangement isn’t intuitively obvious. So, why not wait until additional evidence further resolves the linear sequence?