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Skuas (1 Viewer)

Southern skuas

In case anyone has access there's a new study on skua phylogeography out on Molecular Phylogenetics and Evolution:
"Phylogeography of the southern skua complex – rapid colonisation of the southern hemisphere during a glacial period and reticulate evolution".
Ritz, Millar, Miller, Phillips, Ryan, Sternkopf, Liebers-Helbig & Peter 2008. Phylogeography of the southern skua complex—rapid colonization of the southern hemisphere during a glacial period and reticulate evolution. Mol Phylogenet Evol 49(1): 292–303. [abstract] [pdf]
 
Arctic Skua

Janssen & Mundy (in press). Molecular population genetics of the melanic plumage polymorphism in Arctic skuas (Stercorarius parasiticus): evidence for divergent selection on plumage colour. Mol Ecol. [abstract]
 
Caio J Carlos. How many genera of Stercorariidae are there? Brazilian Journal of Ornithology, Vol. 24 (2), pp. 191-195.

Abstract:
In this contribution I comment on the generic taxonomy of skuas, Stercorariidae, based on the currently available hypotheses of phylogenetic relationships for the group – i.e., the cladograms. Specifically, the different cladograms were examined following Hennig's principle of reciprocal illumination, in which a given hypothesis is evaluated by the extent to which it agrees with competing hypotheses. Currently, all species are often assigned to genus Stercorarius. However, chewing lice- (Insecta, Phthiraptera), behaviour- (territorial display and calls) and molecular-based (mitochondrial DNA) hypotheses of phylogenetic relationships all indicate that Pomarine Skua Stercorarius pomarinus and the species formerly placed in genus Catharacta are monophyletic and sister to a clade comprising Long-tailed S. longicaudus and Parasitic S. parasiticus Skuas. Therefore, contrary to the prevailing view that all species within the family should be placed in a single genus, I argue herein that in a cladistic-based classification by sequencing, both S. parasiticus and S. longicaudus should retain their generic name, whereas S. pomarinus should be transferred to Catharacta, as C. pomarina.

pdf here
 
Janssen, Mundy. 2017. The genetic basis and enigmatic origin of melanic polymorphism in pomarine skuas (Stercorarius pomarinus). Proc. R. Soc. B 284:20171735.
[abstract]
 
I thought they only propagated a proposal to the other committee if it resulted in a change?

Niels
 
I thought they only propagated a proposal to the other committee if it resulted in a change?

Niels

Only if the taxon in question has part of its distribution entirely outside the continent and in the other committee's area; e.g. if the NACC didn't split Blue-vented Hummingbird (entirely in Central America) from Steely-vented (entirely in South America) in this year's proposals, then the SACC would likely not vote on it. But all the jaegers and some skuas occur in both the SACC and NACC, so each Committee can vote on it.
 
But all the jaegers and some skuas occur in both the SACC and NACC, so each Committee can vote on it.
If I may, though... Wouldn't it make sense to update the proposal in this type of case ? (Or, alternatively, wouldn't it have been more sensible to have both committees voting on it simultaneously ?)
I can't really see the added value in a vote by a second committee, in summer 2019, on a proposal dating from 2017 and which is in any case silent about a quite significant late-2017 work (cf. my post #5 above).

("[...], we re-sequenced four unlinked neutral loci across the skuas. For all four loci, the alleles in the pomarine skua cluster with alleles of the great skuas, and for three out of four loci, the pomarine skua even shares alleles with the great skuas (figure 3).")
 
Only if the taxon in question has part of its distribution entirely outside the continent and in the other committee's area; e.g. if the NACC didn't split Blue-vented Hummingbird (entirely in Central America) from Steely-vented (entirely in South America) in this year's proposals, then the SACC would likely not vote on it. But all the jaegers and some skuas occur in both the SACC and NACC, so each Committee can vote on it.

I am still wondering about why this particular proposal is propagated. The maker of the proposal recommends "no change" and the NACC agreed. Recently, I have seen comments to the SACC proposals that there is a backlog of things that should be done. Why then propagate a "no change" proposal to take up time that could be better used on something else? Is it because the person bringing it forward hopes for a different result? But if so, why not openly state that?

By the way, I hope Laurent's comments about the additional information after the original proposal do get forwarded to the committee.

Niels
 
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I am still wondering about why this particular proposal is propagated. The maker of the proposal recommends "no change" and the NACC agreed. Recently, I have seen comments to the SACC proposals that there is a backlog of things that should be done. Why then propagate a "no change" proposal to take up time that could be better used on something else? Is it because the person bringing it forward hopes for a different result? But if so, why not openly state that?

By the way, I hope Laurent's comments about the additional information after the original proposal do get forwarded to the committee.

Niels

The SACC and NACC are completely independent to make their own decisions. So it doesn't matter what the other Committee votes; we (in my case the NACC) should make their own decision. Our goal is to address all publications that advocate changes in the taxonomy or nomenclature, whether we agree or not. Proposal writes often make recommendations, but this need to be the case. In this case, the paper's authors proposed that Catharacta be split from Stercorarrius (parasiticus and longicaudus), so both Committees re bound to vote.
Andy

Andy
 
Seems a good time to dispose of the name 'jaeger' and call them all skuas, in line with the proposal to treat them all in one genus - particularly when the name division doesn't match what genetic division there is :t: o:D
 
Seems a good time to dispose of the name 'jaeger' and call them all skuas, in line with the proposal to treat them all in one genus - particularly when the name division doesn't match what genetic division there is :t: o:D

As they are traditionally named in English anyway..... ;) I've never called them anything else and I don't know anyone who has :t:

John
 
As they are traditionally named in English anyway..... ;) I've never called them anything else and I don't know anyone who has :t:

John

Then I imagine you don't know any Australian or US birders? (Jaeger is used in both countries, per their official checklists.)

(Edit: also the official South African checklist, though I've no idea what common parlance is, and the old Roberts checklist used Skua across the board.)
 
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also the official South African checklist, though I've no idea what common parlance is, and the old Roberts checklist used Skua across the board.

On a recent Cape Town pelagic, the very excellent guide switched between Parasitic Jaeger, Arctic Jaeger and Arctic Skua without comment!

Maybe there is no common parlance :)
 
On a recent Cape Town pelagic, the very excellent guide switched between Parasitic Jaeger, Arctic Jaeger and Arctic Skua without comment!

Maybe there is no common parlance :)


Just for the record.... Jaeger is a Germanic word which means hunter. The Stercorarius sensu stricto do not hunt, while they do occur in the subantarctic... all a bit of a mess really. I think we should just continue to argue this one out for whatever dumb reason.
 
Then I imagine you don't know any Australian or US birders? (Jaeger is used in both countries, per their official checklists.)

(Edit: also the official South African checklist, though I've no idea what common parlance is, and the old Roberts checklist used Skua across the board.)

Yes, but their versions of English are both subordinate - I won't say inferior - to English (is sensu stricto the phrase I'm looking for?) o:D

John
 
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