Really? This is odd and I can’t remember ever having heard of such a thing before. How can two species interbreed into a new species?
They took blood samples from the birds in order to extract DNA.
“By examining the genetics, we have shown conclusively that the Italian sparrow is of mixed origin – it is a hybrid of the house sparrow and the Spanish sparrow,” Dr Saetre told BBC Nature.
“Second, and perhaps equally important – it is not reproducing with the Spanish sparrow, even though the two birds live side-by-side.”
If the birds had been breeding, the scientists say that they would have found genetic “intermediates” – birds with genes from both species.
“But we didn’t find this, so we think [the two species] have formed some kind of reproductive barrier to each other,” Prof Saetre said.
Hey, science people (scientists?), what is up with this?
http://en.wikipedia.org/wiki/Speciation#Hybrid_speciation
Hybrid speciation is common in plants, but there are only a handful of cases in birds. I know Audubon’s Warbler is a recently demonstrated one. There was another recent one but I can’t seem to think of it.
All it (speciation) takes is reproductive isolation of a population. Usually that’s going to mean actual geographic isolation, but hybridization can create mechanical or physiological barriers to reproduction. It doesn’t usually happen as you end up with the hybrids existing (and maybe even thriving), but still regularly interbreeding with one or both parent species.
I was going to say…this is common in plants ^_^
And I wouldn’t be suprised if it isn’t more common in animals, even vertebrates, than we currently know. As Kirby says all speciation takes is reproductive isolation. Differences in behaviours (eg courtship, nesting, roosting) could be enough of a barrier.
disclaimer; i am not a proper scientist yet 😛
Appalachian Tiger Swallowtail got a bunch of press a week or two ago over this, probably lots from there applies and I know the paper on that was open access.
If you can get hold of a copy, J Dennis Summer-Smith book ‘The Sparrows’ has a lot of information on the speciation and variation of the various sparrow species, especially on the 3-way split between House/Italian/Spanish sparrow – its a good read too!
I seem to remember reading about some hybrid finches in the Galapagos that were found to be breeding with each other, but not with either parent species. I think the individuals involved were known to researchers, so it was hailed as a speciation event. There’s no guarantee that this population will keep going, though. It does sort of beg the question of how long an isolated population has to last to be a species; if other qualifications are met, is a species that lasts decades any less valid than a species that lasts millennia?
Look mate, this is a European birding situation. Confused, complicated, completely insane – nothing special okay? If your North American birding mind can’t handle it, keep your nose out of our business and wait for your spring warblers.
Cheers.
@All: Thanks for all the information. I feel smarter for having read your comments.
@Jochen: I think that this incident calls for American intervention. The European Union is simply not up to resolving this.
American intervention?
Boy, am I glad your position as “Official Blogger” at the 2011 Midwest Birding Symposium comes without Secret Service protection and – especially – without the ability to drop bombs on people you don’t like.
🙂
The red wolf (previously found across the southeastern United States, now restricted to a tiny area centered on Alligator River NWR in North Carolina) is likely to have arisen as a hybrid between the grey wolf and the coyote. Consequently, its status as a full species is often disputed. Canids interbreed relatively easily and relatively frequently, so taxonomists have plenty to argue about here.
More info and discussion at my blog:
http://markgchurchill.blogspot.com/2008/07/wolves-defining-undefinable.html
@Jochen & Corey: At the Midwest Birding Symposium, the official bloggers were most certainly relegated to a lesser species of human by the host. 😉
Pomarine Jaeger is an example of a species which may have arisen from a hybrid population of Great Skuas and one of the other jaegers. Genetically, its closest relative is Great Skua, but superficially it is closer to the jaegers.
Actually there are quite a few examples of hybridisation in birds. One of the text book examples is the Herring Gull complex in the Northern Hemisphere;
http://en.wikipedia.org/wiki/Ring_species#Larus_gulls