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HoneyBadgerDC
08-16-2014, 09:13 AM
I have sporadicaly been observing the Los Angeles street pigeons for many years now. I think I may have detected a mutation that has established a distinct breed and may be on it's way to becomming at least a sub-species.

My very possibly wrong concept of what constitutes a sub species is that like individuals seek each other out to breed and recognize one another.

Anyway, what I have noticed is that the birds are basicaly scavengers. It seems that over the years an increasing number of them have been developing sharply hooked strong but small beaks for tearing apart scraps of meat. These same birds tend to be scrawnier and slightly smaller in staure than the average.

What I have been looking for is some evidence that they seek each other out for breeding and avoid the more common variety. The freely intermingle in huge flocks when a feeding frenzy takes place. Last week I saw a small flock of about 12 birds and they all had the hooked beak to one degree or another. I suspect a couple of birds found a nesting spot and several generations of inbreeding took place.

Could this possibly be the start of a new sub species? On a side note someone I know who is familiar with birds suggested it may just be that these birds have been feeding on softer foods such as bread and garbage and are not wearing down thier beaks.

twickster
08-16-2014, 09:20 AM
Moved MPSIMS to GQ, on the assumption that this is a serious question, so that Colibri and other experts can comment.

John Mace
08-16-2014, 11:13 AM
You have 2 subspecies when 2 populations which normally would breed with each other and produce fertile offspring do not do so because they are separated by some barrier. Normally, that barrier would be geographical. If it's a behavior that prevents two populations in the same geographical range from mating, then they are usually considered to be 2 separate species (think coyotes and wolves).

It's hard to imagine, though, that you'd suddenly get a population within a large, easily mixed population that would develop a physical difference and a mating preference based on that difference at precisely the same time.

More than likely you are experiencing confirmation bias.

Broomstick
08-16-2014, 11:44 AM
It's possible the pigeons with "hooked" beaks who scavenge meat are surviving and reproducing better than the "standard" pigeon, so you get more and more of the new variety as time goes by. However, you do have to watch out for confirmation bias.

HoneyBadgerDC
08-16-2014, 11:45 AM
You have 2 subspecies when 2 populations which normally would breed with each other and produce fertile offspring do not do so because they are separated by some barrier. Normally, that barrier would be geographical. If it's a behavior that prevents two populations in the same geographical range from mating, then they are usually considered to be 2 separate species (think coyotes and wolves).

It's hard to imagine, though, that you'd suddenly get a population within a large, easily mixed population that would develop a physical difference and a mating preference based on that difference at precisely the same time.

More than likely you are experiencing confirmation bias.

I actually do agree with you, over the past 30 years or so I seem to be seeing thse hooked bill pigeons more and more often. I have never seen any evidence of rock doves or city pigeons differentiating between breeds and once domestics have gone wild whatever breed they are quickly dissipates into the main population. That is kind of why I found it odd that a type seems to be emerging.

Is there any such thing as a softer type divergence where a preference for some type of food may lead them into slightly different areas and expose like individuals to breeding opportunities more frequently?

One example might be that a particular street is kept cleaner and less opportunity for foraging unless a bird was willing to hop into a trash can. The bigger flocks might avoid these areas favoring easier pickings off the side walks. The birds who tended to dive into the trash cans had similar recessive genes in common and they tended to meet up more often because of where they foraged.

Colibri
08-16-2014, 12:20 PM
First of all, you would have to demonstrate that the differences involved have a genetic basis. They could easily be due to developmental changes, or even as has been suggested changes in diet.

However, even if it were genetic, you would need a great deal more isolation of the population in order to evolve differences equivalent to those found in typical subspecies. As long as this population is interbreeding with other nearby ones, that's unlikely to develop.

la fille intellectuelle
08-17-2014, 06:17 PM
I have sporadicaly been observing the Los Angeles street pigeons for many years now. I think I may have detected a mutation that has established a distinct breed and may be on it's way to becomming at least a sub-species.

My very possibly wrong concept of what constitutes a sub species is that like individuals seek each other out to breed and recognize one another.

Anyway, what I have noticed is that the birds are basicaly scavengers. It seems that over the years an increasing number of them have been developing sharply hooked strong but small beaks for tearing apart scraps of meat. These same birds tend to be scrawnier and slightly smaller in staure than the average.

What I have been looking for is some evidence that they seek each other out for breeding and avoid the more common variety. The freely intermingle in huge flocks when a feeding frenzy takes place. Last week I saw a small flock of about 12 birds and they all had the hooked beak to one degree or another. I suspect a couple of birds found a nesting spot and several generations of inbreeding took place.

Could this possibly be the start of a new sub species? On a side note someone I know who is familiar with birds suggested it may just be that these birds have been feeding on softer foods such as bread and garbage and are not wearing down thier beaks.





So many people suffering in this world,yet you take the time to discuss whether vermin choose to reproduce.




:confused:

cochrane
08-17-2014, 06:25 PM
So many people suffering in this world,yet you take the time to discuss whether vermin choose to reproduce.




:confused:

So many people suffering in the world, yet you take the time to shit in the thread. If you haven't noticed, the name of the forum is "General Questions," not "How to Improve the World." :rolleyes:

Colibri
08-17-2014, 06:53 PM
So many people suffering in this world,yet you take the time to discuss whether vermin choose to reproduce.

:confused:

Moderator Note

la fille intellectuelle, if you don't see the point to a GQ thread, there's really no point in responding to it. No warning issued, but don't do this sort of thing again.

Colibri
General Questions Moderator

TSBG
08-18-2014, 08:40 PM
Honey Badger, why not try the LA Museum of Natural History? They have recently opened a big exhibit on the local ecology/flora and fauna of the city and region; IME people at museums and such love to share what they know with someone who takes the trouble to call up.

HoneyBadgerDC
08-19-2014, 01:46 AM
Honey Badger, why not try the LA Museum of Natural History? They have recently opened a big exhibit on the local ecology/flora and fauna of the city and region; IME people at museums and such love to share what they know with someone who takes the trouble to call up.

Thats a good suggestion, I have been wat6ching all manor of critters for about the past 60 years and have several observations I would like to run past them.

purplehorseshoe
08-19-2014, 02:33 PM
Let us know if the museum folks have any interesting insights -- the pigeon beaks, your other observations, the meaning of life, etc.

HoneyBadgerDC
08-19-2014, 02:39 PM
Let us know if the museum folks have any interesting insights -- the pigeon beaks, your other observations, the meaning of life, etc.

I find the meaning of life does involve pigeon beaks and other observations. I have no idea what gives your life meaning, maybe just feeling qualified to judge others gives you meaning.

Isilder
08-20-2014, 04:45 AM
There is a law against feeding pigeons there in Los Angeles , so the better scavenger may be winning.