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Corvidae (1 Viewer)

With the disclaimer that I haven't read the whole paper yet, so it might have been covered already...

But the lack of F1s suggests to me that they can tell each other apart now, but that they couldn't in the past. This suggests some sort of reinforcement pattern happening in this system, which would be very neat!

Full text of the draft is linked above: https://www.biorxiv.org/content/10.1101/491654v1.full

Its not the final, but I expect few changes.

I wouldn't get your hopes up - I think the mention of no F1s is to suggest that these are populations that have been intergrading for a long time now - ie this is not "new" hybridization nor are hybrids strongly selected against; in either case one would expect to see a lot of first generation hybrids in the population.
 
There's no F1s because there aren't any 'pure' birds left to produce F1 chicks, they're all hybrids, the whole lot of them, from the Alaskan border all the way down to NW Washington :t:
 
There's no F1s because there aren't any 'pure' birds left to produce F1 chicks, they're all hybrids, the whole lot of them, from the Alaskan border all the way down to NW Washington :t:

Nope, plenty of "pure" birds, as evidenced by the admixture/structure plot. Though I conceed that the lack of F1s could be due to the hybrid zone being too broad so that pure individuals no longer come into contact. Still, this leaves many fascinating questions to be answered about reinforcement and potentially character displacement. It'll be interesting to follow future papers from these authors.
 
Nope, plenty of "pure" birds, as evidenced by the admixture/structure plot. Though I conceed that the lack of F1s could be due to the hybrid zone being too broad so that pure individuals no longer come into contact. Still, this leaves many fascinating questions to be answered about reinforcement and potentially character displacement. It'll be interesting to follow future papers from these authors.
Think I must have misread that plot a bit - I assumed the blue ones down the left edge were the samples from Alaska, and the red ones down the right edge were samples from S/E of the hybrid zone.
 
Poelstra, Vijay, Hoeppner & Wolf (in press). Transcriptomics of colour patterning and colouration shifts in crows. Mol Ecol. [abstract]

[Hooded Crow Corvus (corone) cornix is treated as a distinct species by HBW, IOC, eBird/Clements, BOURC and CSNA; but not by BirdLife, H&M4 or AERC.]



The more I think about it, the more I don't know what to think about the taxonomy of the Corvus corone species complex. Is cornix a distinct species of corone or not and what do the most recent works say ? It's the mess in my mind.
 
The situation to my mind is that these two taxons are interbreeding where they overlap. The difficulty is in defining whether that zone of hybridization is narrow and indicates some type of selection against the intermediate forms or if the hybrid zone is wide and indicates no such selection.

Niels
 
The situation to my mind is that these two taxons are interbreeding where they overlap. The difficulty is in defining whether that zone of hybridization is narrow and indicates some type of selection against the intermediate forms or if the hybrid zone is wide and indicates no such selection.

Niels
Yep - it seems the hybrid zone is 'too narrow' for the expected degree of post-glacial natural dispersal of hundreds / thousands of generations, i.e., hybrids don't survive well or have low productivity, which is used to support species status. If hybrids were as fit and productive as non-hybrids, the intergrade zone would encompass almost the whole of Europe by now.

PS one taxon, two taxa ;)
 
PS one taxon, two taxa

I used to have that much classical education, I guess I am too busy/stressed/whatever you want to call it to think about that ... errare humanum est

Niels
 
Zhigir D.R., Red’kin Ya.A. (2020). Subspecies of the Oriental Carrion Crow Corvus (corone) orientalis Eversmann, 1841. Russian Journal of Ornithology 29(1955): 3451-3468

We studied 306 Eastern Carrion Crow skins. As a result, it was possible to confirm the manifestation of geographical variability in this species, expressed in variations in the overall size, size and shape of the bill and the length of the tarsus. 8 signs were measured from each skin: wing length (measured with a tape measure from the outside); wing tip (primaries projection) and tail length (with a ruler), tarsus length; bill length – from the base of the nostril, bill length from the front edge of the nostril; bill height – at its highest point; bill width – at the level of hard bristles at the base of the upper mandible. Birds from 4 groups were compared separately: adult males (M ad), first-year males (M sad), adult females (F ad), and first-year females (F sad). The subspecies do not differ in colour. As a result, we state the reality of five subspecies, two of which we describe for the first time.

Corvus orientalis orientalis Eversmann, 1841
Corvus orientalis turkestanicus Zhigir et Redkin subsp. nova
Corvus orientalis saghalense Kumagai, 1926
Corvus orientalis lobkovi Zhigir et Redkin subsp. nova
Corvus orientalis interpositus Laubmann, 1917
 
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