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Message: <blockquote data-quote="Kirk Roth" data-source="post: 1882898" data-attributes="member: 85015">I find it disappointing that the article doesn't address Clark's claim of a lack of interbreeding between harlani vs. alascensis/borealis/calurus.  Indeed, Clark is formally cited twice: once for his field guide and for his article in Birding.  Oddly, his article is cited as "in press," despite Liguari's later Birding article getting a full citation.  Some lazy editing there!  But at any rate, I feel that its a bit irresponsible for the Hull article not to discuss Clark's findings, despite Clark's assistance to their field work.Unless I'm mistaken, the article uses the same mtDNA markers that have been used in other hawk analyses.  This seems an odd convention to me - as if hawk DNA only varies in 17 particular spots.  All of this just before the article states "These data suggest that the Mc1r locus in B. jamaicensis is not responsible for breast color variation or the variable melanin-basedplumage patterns observed in B. j. harlani."  To me, this seems to mean "we studied several genes, but not the ones that make harlani distinct."  If the analysis instead honed in on melanin-related genes, I would expect the data to show either a closer relation between harlani-calurus (contra Hull's results) or perhaps more distinction, depending obviously on the mechanisms of melanism between the two taxa.  I'm trying to say that it would seem a real possibility that Hull's analysis could have missed key genetic pieces.  The article addresses this with a half sentence on the last page: "Potential mechanisms include: 1) a B. j. harlani-specific gene or gene-complex, or 2) particular environmental, temporal, or physiological conditions within the B. j. harlani range interacting with the standard B. jamaicensis genotype without involvement of a unique B. j. harlanigenotype." I bring this up because even a single gene can cause biological speciation, and frankly I have a hard time accepting that mtDNA and microsatellites change in constant rates, along all taxa, such that it can be the basis for such bold statements as the Hull paper makes about speciation and lack thereof.One other note about point #2 in the quote in the paragraph above - For this scenario to be true, some sort of phenotypically plastic gene would have to be present in harlani and borealis, but not alascensis.  Unfortunately, alascensis was excluded in this study, leaving out an important piece of the puzzle.  Too bad we can't get a good study limited to Alaska and northwest Canada, integrating ecological, morphological, and genetic data.  But I suppose that would put Harlan's Hawk researchers out of a job.    One of our understandings of Clark's remarks is incorrect.  The last I heard from him, he admitted to not knowing what exactly the true krideri morph is.  However, I can attest that a great many winter "krideri" reported here in the midwest end up being light morph harlani, especially juveniles.</blockquote>

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