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Crossbills (1 Viewer)

V useful. Interesting that eg on Corsica, as well as the corsicana ssp, there's a "Corsican" curvirostra ssp that also lives on pine.... plus 2 others ("Phantom" and "Glip"). Would be interesting to get some DNA work done to compare against the vocal studies, big job though.
 
Interesting that eg on Corsica, as well as the corsicana ssp, there's a "Corsican" curvirostra ssp that also lives on pine.... plus 2 others ("Phantom" and "Glip").

Actually, the "Corsican" type of Förschler and Kalko 2009 is the subspecies corsicana. (And the "Phantom"-type calls these authors recorded in Corsica came in fact from the same corsicana flock as the recordings they labelled "Corsican"...)

Would be interesting to get some DNA work done to compare against the vocal studies, big job though.

Would be good to have it done, but I'm really unconvinced it would work. The only thing one can tell from a plain-winged crossbill's DNA currently is whether it is American or Old World.
 
Thanks for inadvertently pointing out my error here, "PXR5" - Foerschler and Kalko's "vocal type H" is actually the same as Clouet and Joachim's corsicana, so I've now corrected the pdf and it should be updated online soon.

Incidentally, my intention is to keep updating this table as a synthesised public resource, so if anyone can cite published synonimisation, call equivalents, new taxa and call types, etc, I'd be grateful if they were pointed out. If anyone wants to highlight mistakes without gloating too much, constructive criticism will also be welcome! It's no excuse, but I had to absorb about 200 papers in the space of a week to write the article, so the occasional sprat may have got through the net ...

At least two more call-type academic papers are allegedly on their way early next year, but will all become clearer or murkier ..?

EDIT: Damn, Laurent got there first!!

Cheers
D
 
To be fair David, a very interesting resource already. Think the idea of it being added to by those in the know is an excellent idea.
What i was hinting at is something you mentioned... the idea of some of these different call types belonging to the same taxon, hence my suggestion of comparing vocalisations with DNA samples, although it seems they're too closely related for that to be practical?
TTFN.
 
Thanks for the summary sheet

off the top of my head, didn't the Newfoundland form go "extinct" when red squirrels were introduced? Or am I thinking of a different form?
 
Thanks for the summary sheet

off the top of my head, didn't the Newfoundland form go "extinct" when red squirrels were introduced? Or am I thinking of a different form?

This is indeed true - this also happened to the (apparently unnamed) Cypress Hills form, too. I should add the word 'extinct' to the table for percna, but its non-existant status is mentioned in the article.
 
Thanks for the summary sheet

off the top of my head, didn't the Newfoundland form go "extinct" when red squirrels were introduced? Or am I thinking of a different form?

Someone on Bird Forum had suspected percna in their garden on sunflowers a few years ago over several summers in Newfoundland. Ornithologists came out and recorded the call, and as I recall the calls were different from the then described New World types ( or matched percna, I can't recall off-hand). They also caught a couple of birds apparently. The guy's name was Lester Rees and there are photos in the gallery under LWR. It is possible the crossbills were from the mainland.

I think it is a bit like IBWO - there is a reference recording of perca somewhere, and of course collected specimens. Worth mentioning that there is actually a species action plan for percna also, though not sure if it has been dropped.

I will check and get back to you on this......
 
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Someone on Bird Forum had suspected percna in their garden on sunflowers a few years ago over several summers in Newfoundland. Ornithologists came out and recorded the call, and as I recall the calls were different from the then described New World types ( or matched percna, I can't recall off-hand). They also caught a couple of birds apparently. The guy's name was Lester Rees and there are photos in the gallery under LWR. It is possible the crossbills were from the mainland.

I think it is a bit like IBWO - there is a reference recording of perca somewhere, and of course collected specimens. Worth mentioning that there is actually a species action plan for percna also, though not sure if it has been dropped.

I will check and get back to you on this......

......I was right, but the jury is still out ( as always with Crossbills !). See HERE

Interestingly, there is only a series of recordings of a single presumed percna from 1981 on Newfoundland.
 
A rant about crossbills

There is some really interesting research going into these birds at the moment. Documenting the differentiation in vocal types is an important part of understanding more about them. However, I am a bit concerned at notes on this forum, and the recent description published in Auk (which was rejected by AOU), of new "species" of crossbills based on differences in song, but showing no diagnosable morphological or mtDNA differences.

The obvious "null hypothesis" is that crossbills' songs are learned. There may be a bunch of different populations which roam around as groups and possibly have small differences in bill shape and food preferences. I am not saying that this is definitely what is happening. However, the papers I have read on the topic so far have not shown that this is not what is happening. Based on distinctive observed differences in song, one could perhaps call some of these bands or populations "subspecies" based on current knowledge and people might feel that naming some of them is appropriate on that basis however.

In Homo sapiens, if you go to the border between, say, the USA and Mexico or France and Spain, there is strong differentiation in voice across the border. However, we know that this is learned and not innate. We are all the same species.

For some Tyrant-Flycatchers, there are interesting studies by Kroodsma and others. Empidonax species A has been reared in captivity by Empidonax species B or whilst frequently playing recordings of the song of Empidonax species B. Emplidonax species A does not learn the song of species B, and actually sings like a normal species A. Until someone takes a pullus or egg Crossbill of song type A into captivity and plays it songs of B whilst it grows, and we can see what its song is, there is likely to be considerable scepticism about the claims of multiple species in this group (and that includes Scottish Crossbill). This instance is different from that of various other oscines with different songs, in that for crossbills, other diagnosable differences between populations are so elusive and the one character out there might be learned rather than innate.
 
Craig W. Benkman, Thomas L. Parchman, and Eduardo T. Mezquida, 2010. Patterns of coevolution in the adaptive radiation of crossbills. ANNALS OF THE NEW YORK ACADEMY OF SCIENCES, Volume 1206, Issue 1, September 2010, Pages: 1–16.
Abstract
 
There is some really interesting research going into these birds at the moment. Documenting the differentiation in vocal types is an important part of understanding more about them. However, I am a bit concerned at notes on this forum, and the recent description published in Auk (which was rejected by AOU), of new "species" of crossbills based on differences in song, but showing no diagnosable morphological or mtDNA differences.

The Benkman paper from the Auk indicates that South Hills vs. Type 4 or Type 2 Crossbills show extremely limited interbreeding. At the very least, this means they should be "on the radar" as a potential biological species. The observation that there is little or no evidence for interbreeding among the different call types is the reason that all this crossbill research is even occurring... it would be extremely remiss not to mention that aspect here.

Based on distinctive observed differences in song, one could perhaps call some of these bands or populations "subspecies" based on current knowledge and people might feel that naming some of them is appropriate on that basis however.


Subspecies, by definition, inhabit different geographical areas. The different crossbill types cohabitate with little evidence for interbreeding, thus the term "subspecies" is inappropriate. I like the "Call Type" terminology somewhat. I'd rather a term other than "type" be used ("crossbill type" might mean two different things), but now I'm just being picky.

For some Tyrant-Flycatchers, there are interesting studies by Kroodsma and others.

Kroodsma's research is also instrumental in demonstrating that tyrant-flycatchers and finches (among other birds) have very different methods of song development. Tyrant-flycatchers have innate songs, whereas finches learn their songs. In other words, this is an apples to oranges comparison. I think a more fruitful (so to speak) approach would be to compare crossbill differentiation with tit/chickadee differentiation, although that is a developing field as well. Speaking of apples and oranges, it should go without saying that crossbill and human speciation are not comparable.
 

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