Posted on 12/03/2009 9:53:05 AM PST by decimon
By feeding birds, you could alter their evolutionary future, with changes visible in the very near term, scientists now conclude.
Due to winter bird-feeding, what was once a single population of birds has, in fewer than 30 generations, been split into two groups that do not interbreed, despite the fact that they continue to breed side by side in the very same forests.
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Over the course of three-and-a-half years, the scientists followed birds known as blackcaps (Sylvia atricapilla) in Central Europe after humans began offering food to them. A recent divide has sprung up, with two groups following distinct migration routes in the winter - one southwest in Spain, the other northwest in the United Kingdom.
"The new northwest migratory route is shorter, and those birds feed on food provided by humans instead of fruits as the birds that migrate southwest do," Schaefer said. "As a consequence, birds migrating northwest have rounder wings, which provide better maneuverability but make them less suited for long-distance migration." They also have longer, narrower bills that are less equipped for eating large fruits like olives during the winter.
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(Excerpt) Read more at news.yahoo.com ...
Are they demanding pepsi in the bird feeder?
We feed birds all winter starting in October when we can keep the bears from destroying the feeders and running off with suet cakes.
Must be my Wife again.
The Grackles and Euro-trash dove love our yard.
Winter is when they need it. I figure if you feed 'em you breed 'em so I would feel I was being irresponsible if I cut them off in the cold months.
Is that like the Vegans vs. the Meat Eaters?
Yeah, there are some birds that should have 'Hoover' on their wings.
That’s Great.The next thing they’ll do is ban the feeding of birds.
I guess these people have nothing better to do then screw
around with peoples lives.
From what I have seen birds are not stupid.During the winter they will eat at the feeders and during the summer they hunt for insects.My feeders are barely touched during the summer by the birds.They consume much less seed.
Is that like the Vegans vs. the Meat Eaters?
In my yard, vegans versus meat eaters would amount to the birds I feed directly (bird seed) versus the birds eating those birds, the merlins.
I wish I could say that. My favorite seed became hulled sunflower seeds but I can't afford the amount the little eating machines pack away.
BTW, spotted this guy in my back yard a couple of days ago.
He was over three feet tall.
Cute little bird...Is that for real or shopped?
Looks like he needs something to eat RK.
He’s real. We have a creek that runs through our back yard, and get all kinds of wildlife down there; deer, armadillos, raccoons, and a ton of birds. The only problem is that coyotes also come through on occasion. Spotted a black tailed fox one day, it’s the first one I’ve ever seen in my life. I didn’t even know there were any in Texas.
Nice looking bird, good shot too!
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