Subject: [Tweeters] 15 new North American Bird Species by DNA
Date: Feb 19 20:55:20 2007
From: Michael Hobbs - birdmarymoor at verizon.net
Tweets - Often when I'm birdwatching with my wife - who is a semi-interested birder - I'll try to explain to her how to tell, say, a Long-billed Dowitcher from a Short-billed Dowitcher, and she'll come back at me with the line, "Yes, but can THEY tell each other apart?"
I think that's the crux of things here. There's no magic DNA percentage threshhold that says 2 species vs. 1. In fact, the smallest genetic difference could make two populations unable to interbreed - even a single base-pair difference could conceivably be enough to, well, prevent conception. And on the other hand, there could be a huge range of genetic difference within a single breeding population.
That is to say, I mostly believe in the "Biological Species Concept" - (very loosely) if they interbreed freely, they're one species; if they don't, they're two.
Thus, I find myself unable to agree with the notion that White-crowned Sparrow and Golden-crowned Sparrow might be the same species.
At the same time, I don't blink at the notion that Great Danes and Chihuahuas are the same species, even though I don't believe that Great Dane can successfully breed with Chihuahuas.
The entire notion of species is our attempt to classify that which may not be suitable for classification.
However, we'll continue to try. And I expect the result of this DNA barcoding is that:
a) They'll have to add more precision to the barcoding to allow separation of some of these pairs/clusters
b) More research will be done on those species called out in this report
I would expect that the research done will focus, not on DNA, but on the usual - tracking of songs, behaviors, pairings, hybrid zones, etc. There will probably be several splits but only a few lumps.
What will this mean for birders? Well, we're already used to counting just Northern Flicker, while noting as an aside almost whether they're Red-shafted or Yellow-shafted or intergrade. We could well be doing the same thing with Townsend's Warbler and Hermit Warbler at some point. Conversely, I just went through the process of using a map to reassign my old sightings of Blue Grouse to Dusky vs. Sooty. Probably a lot more of that too.
I'd rather just bird...
== Michael Hobbs
== Kirkland, WA
== http://www.marymoor.org/birding.htm
== birdmarymoor at verizon.net
----- Original Message -----
From: Douglas Canning
To: Tweeters
Sent: 2/19/2007 7:32:11 PM
Subject: Re: [Tweeters] 15 new North American Bird Species by DNA
And there's yet another story on the Environmental News Network site at http://www.enn.com/today.html?id=12246 (I haven't been able to read the other two - they don't like the way I block their pop-ups.)
The researchers are quoted as saying, "...there might be more than 1,000 new species of birds on top of 10,000 identified so far." The article closes with: "The scientists are hoping to raise $100 million to compile a barcode of life -- 10 million DNA records of 500,000 animal species by 2014."
Looks like we're approaching the final triumph of laboratory mechanics over field biologists. Be interesting to see what the science really is. I agree with Jerry that this stuff reads more like a news release from an institutional PR office.
But, if this is as goofy as looks like right now, it'll save me the cost of never having to buy another updated field guide to keep up with stuff that makes little or no sense out in the real world.
Doug Canning
On 18 Feb 2007 at 19:12, Tangren Family wrote:
From: Tangren Family <tangren.family at verizon.net>
Subject: Re: [Tweeters] 15 new North American Bird Species by DNA
Date sent: Sun, 18 Feb 2007 19:12:10 -0800
To: Tweeters <tweeters at u.washington.edu>
> >This article is intrigueing, but I wish it provided more details on
> >species studied. Do any Tweeters have anything they could add?
> >
> >http://www.sciencedaily.com/releases/2007/02/070218194535.htm
> >
> >
> >Scott R a y
> >AFLAC
> >Moxee, WA
> >509.961.2625
> >mryakima at gmail dot com
> >_______________________________________________
> >Tweeters mailing list
> >Tweeters at u.washington.edu
> >http://mailman1.u.washington.edu/mailman/listinfo/tweeters
>
> This looks like it was assembled by university press relations--low on
> details but high on hype. Without details, I'm thinking that most of
> the bird splits have been previously proposed, and that some in the
> past may have been treated as such for phenotypic reasons.
>
> The similarities appeared somewhat surprising--golden-crowned and
> white-crowned sparrow for one. If in fact they are proposing species
> lumps, then this would fly in the face of the conventional definition
> of a species and the importance of reproductive isolation.
>
> It does provide interesting data to consider. However, I believe much
> of the biology is missing from the press release, and the results are
> not as significant as the press release would have us believe.
>
> --Jerry <tangren.family at verizon.net>
>
>
*******************
Douglas Canning
Olympia, Washington
dcanning at zhonka.net
*******************
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