Wondering about pigeons - Input Junkie
Wondering about pigeons|
Most animals look very similar to other members of their species in the same locality, but city pigeons' feather patterns haven't converged. Any idea why?
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comments so far on that entry.
Because birds bred by pigeon hobbyists influence the "wild" population? Also because pigeons aren't subject to a lot of the
premeditation predation that ought to cut down on the number of odd-colored/more distinctive individuals (and pigeons seem to have a lot of genetic diversity)?
ETA: to correct auto-correct.
Edited at 2014-07-11 02:27 pm (UTC)
|Date:||July 11th, 2014 02:44 pm (UTC)|| |
There was that Russian biologist who bred foxes for reduced fear of human beings—in effect, for "tameness." His domesticated foxes ended up with widely variable coat color patterns. Could city pigeons have undergone something like the same process? They're certainly not completely unafraid of humans, but they don't avoid us all that strongly, especially if we're eating something.
Pigeons don't have much to fear from humans in cities, and we're their primary food-source there. The predators they have to worry about are hawks and falcons
: more variable patterns may be advantageous as 'camouflage', to break up the pigeon-shaped outline.
|Date:||July 12th, 2014 04:39 pm (UTC)|| |
This was the first thing I thought of too.
To clarify a bit, there is a marking phenomenon which only(?) appears in domesticated mammals: dogs, cats, horses, cows, and pigs. It's the random blotchy spot pattern. When they bred domesticatable foxes by selecting for social-psychological traits of tolerating humans repeatedly over decades, this pattern appeared on the foxes.
So I too am wondering it this is the avian equivalent.
|Date:||July 11th, 2014 03:01 pm (UTC)|| |
I believe it's because the pattern that pigeon feather color genes control for is "brindle" and not "white here, grey there, iridescent over there." I'm thinking about calico cats and merle and spotted dogs -- the placement of the colors on each animal is unique, as it is on pigeons.
Pigeon genetics are pretty diverse and complex: there's the base "wild type" which is grey with dark bars on its wings and a blue-cast iridescent head and then a host of mutations that effect expression and distribution of color (and extra feathering, as on legs and neck, etc.). Pigeon fanciers have documented dozens of different mutations, and I believe that their "almond" is the equivalent of merle in dogs.
I surmise it may be because female pigeons find variation in male plumage to be sexy in itself, and thus are selectively more attracted to the boys who stand out in the crowd.
|Date:||July 11th, 2014 11:43 pm (UTC)|| |
, the fancy pigeons are domesticated They would never survive in the wild. Search the Internet for "Jacobin pigeons," for an example.
I tried to post a pic of one here from a file I have of an image, but I can't get comments to accept it. Probably the error is mine. I haven't learned all the ins-and-outs of LJ yet.
It was batwrangler
who mentioned birds bred by pigeon hobbyists, not me.
I know someone who's got a pair of Jacobins, and they're about the most helpless birds imaginable; they wouldn't survive half a day outdoors. Around here, the Wild has a habit of coming calling by night; hence the expression 'chicken fortress'
- nothing domesticated survives without one, not even big mean African geese.