On Tue, 14 Oct 2003 15:16:47 +0000 (UTC), johnsuth{at}nospam.com.au
wrote:


> 
>From New Scientist (Antipodean edition) 11th October 2003, p. 57, The
last word.  R.P.   
>Dales, Professor Emeritus of Zoology, University of London, UK writes
"Flamingos feed on   
>small crustaceans, which they sieve through their specially adapted bills." 
> 
>Sounds like God organised an unscheduled production run of the new
design of flamingo bill.    
>I wonder what the old design looked like.  Did the flamingos request a
new design to take   
>advantage of a plague of crustaceans, or did offspring just appear with
it as a result of   
>virus, bacteria or radiation burst altering the DNA? 
> 
>Perhaps I should write to the good professor and ask him what he meant
by "specially   
>adapted". 
> 
>

The bill of the flamingo is clearly very similar in general form and
composition to all bird bills, but the details of its structure are
very unusual.  That is, it is certainly a bird bill but it is a very
unusual one.  Flamingos feed by taking in water into their mouths and
forcing it out through the slits in the fringed bill.  As a result,
particles larger than the slit width, small crustaceans for example,
stay in their mouths while the water and all the smaller stuff leaves.
They then eat whatever they catch that way.  It is apparant that the
behavior and the specialized structure somehow "match" each other and
seem particularly appropriate as a method of filter feeding. 

Given the fact that bird bill size and shape are well known to be
heritable characters and given the fact that bird bill size and shape
are well known to be highly correclated with feeding behavior and
given the fact that such correlations have been well studied (as in
the Galapagos finches) and given the fact that other filter feeders
(like baleen whales) have feeding structure somewhat similar in form
to the fringed bill of the flamingo, then it seem quite likely that
the bill of the flamingo and the feeding behavior have coevolved as
evolutionary adaptations to a particular ecological mode of life,
filter feeding.

In other words, the bill is specially adapted for filter feeding.

I don't understand your problem!  This usage of the term "adaptation"
is exactly what it is supposed to be -- a change in a presumably
heritable characteristic that  presumably makes the owner better able
to cope with the problems of its existence (getting food) and so
presumably confers a selective advantage on its owner as compared with
flamingos that have different bills.  As a result, under the influence
of natural selection, modern flamingos have bills highly suited
(adapted) to this mode of feeding while the presumed ancestors had
more "ordinary" bird bills and, presumably, a very different pattern
of feeding more like that of other birds.  The flamingos form an
entire order (Phoenicopteriformes) and I don't know the evolutionary
histor.  I also don't know exactly how much experimental or
paleontological data there is to confirm all the the "presumably"
statements I made, but every statement agrees so well with so many
other factors of evolution that pople have no hesitation in making
such claims without all the weasel words.

Adaptation is simply the end result of natural selection.  Or are you
just an evolution denier at work here? The only reason I have spent so
much time on you is that I thought you might be a biology student or a
person interested in biology but were confused on how the term
"adaptation" is used.  If you want to deny that it occurs, that all
"apt" solutions to problems must be specifically designed, then that
is a different story.
---
þ RIMEGate(tm)/RGXPost V1.14 at BBSWORLD * Info{at}bbsworld.com

---
 * RIMEGate(tm)V10.2áÿ* RelayNet(tm) NNTP Gateway * MoonDog BBS
 * RgateImp.MoonDog.BBS at 10/14/03 8:46:14 PM