Comments on: British birdfeeders split blackcaps into two genetically distinct groups

By: frances Barnfield

frances Barnfield — Wed, 17 Feb 2010 12:41:17 +0000

We have a pair of blackcaps in our garded, the male first sited 15th Dec 09. My husband and I have been putting on the bird table the usual bird seeds but when we add apple we have noticed the male blackcap becomes very aggressive with sparrows,robins,chaffinch and dunnocks, not allowing them to feed. Is this their normal behaviour?

By: Laurance Johnson

Laurance Johnson — Thu, 21 Jan 2010 13:39:22 +0000

‘They also have narrower and longer beaks, for they are generalists that mostly eat seeds and fat from garden feeders’.
I do have some trouble with this research. Statements such as that above are far to general. Birds within any species can show size differences when subjected to measuring like this. By that I mean one would need to take measurements from a large sample of birds in other countries, as well as large samples from here, as we now know that most of the birds that winter here are from the continent. There may well be a geographical size difference notwithstanding birdfeeders. I simply can’t see the connection to bird feeders either. I fail to understand how that connection has been made. That having been said it is an interesting article in any event.

By: Betsy

Betsy — Thu, 17 Dec 2009 04:22:59 +0000

Not sure if I'm supposed to feel good or bad after reading this! I'll be the first to admit I'm a Birdfeeders.com addict! But personally I think the changes in migratory patterns are natural and would happen even if there weren't humans, food sources come and go on their own as well.

By: Dan

Dan — Mon, 07 Dec 2009 20:53:32 +0000

DD,
Many thanks for the link to my page on Ambelopoulia.
Ed,
Great article, but a question as someone who hasn’t gotten a chance to download the article yet and read it – what are the Brits feeding the incipient species with? Are they feeding the insect or seed/fruit part of the Blackcap diet?

By: MattK

MattK — Sun, 06 Dec 2009 03:07:43 +0000

Great write up Ed. I think this is one of the coolest evolution stories of the year.

By: DD

DD — Sat, 05 Dec 2009 09:15:59 +0000

I was just reading about Black Caps in Cyprus being caught in poacher’s nets and sticky lime sticks for sale to tourist cafes.
(Never heard of ‘em before.)
http://migration.wordpress.com/

By: David Allen

David Allen — Fri, 04 Dec 2009 12:39:21 +0000

Even odder actually, because Britain has its own summer population of Blackcaps which migrate to Spain in the winter to be replaced by German birds. For several years it was thought that the winter Blackcaps in the UK were birds that bred here in the summer and remained throughout the winter. Wrong. The Brtish population goes to Spain in the winter (Blackcaps haven’t been affected by the strength of the Euro in the same way as Homo sapiens)and part of the German population moves here.

By: Briana

Briana — Fri, 04 Dec 2009 02:19:41 +0000

Neat find. I wonder if this finding would be a good opportunity to study genetic assimilation… it might be a reason they diverged so quickly.

By: Matt G

Matt G — Thu, 03 Dec 2009 23:26:03 +0000

Do they carry coconuts with them as they migrate (for all you Monty Python fans!)?
(Ed- there’s a “were” in the second paragraph that doesn’t belong).
Nice piece. Looks like it could become another case of sympatric speciation.

By: Blackbird

Blackbird — Thu, 03 Dec 2009 20:15:31 +0000

Why do they have to cross the Alps to fly to Spain? I would have thought they have to cross the Pyrenees (and they should cross the Alps to go to Italy). Cool post though!