Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site cadovax.UUCP
Path: utzoo!linus!decvax!decwrl!greipa!pesnta!pertec!scgvaxd!trwrb!trwrba!cadovax!keithd
From: keithd@cadovax.UUCP (Keith Doyle)
Newsgroups: net.origins
Subject: Re: The Scientific Case for Creation: (Part 17)
Message-ID: <632@cadovax.UUCP>
Date: Wed, 22-May-85 23:33:09 EDT
Article-I.D.: cadovax.632
Posted: Wed May 22 23:33:09 1985
Date-Received: Sun, 26-May-85 21:15:11 EDT
References: <359@iham1.UUCP>
Organization: Contel Cado, Torrance, CA
Lines: 157

>
>> [Jeff Sonntag]
>>     No half-developed eyes?  Numerous single-cell animals have
>> half-developed eyes.  Some multi-cellular animals have *very* simple eyes.
>
>> [Keith Doyle]
>> Depends on how you look at it.  All species appear half developed, depending
>> on what you think they are developing toward.

>[Paul DuBois]
>I think that neither of these statements is worthy of serious
>consideration until they are given some support.  (For instance, Mr.
>Sonntag can give the phylogeny of vision.  Mr. Doyle can show what
>half-developed visual structures turn into.) 

What I was trying to say, is that the human eye can be considered a
half-developed-eye if you consider it is only on its way to becoming
an even higher developed eye through evolution.  (maybe man of the
year 20,000 will have X-RAY eyes and/or telescopic vision! :-)

>Lisa J Shawver, "Trilobite eyes: An impressive feat of early evolution".
>Science News, 105(5), 2 Feb 1974.
>
>"Although extinct for more than 300 million years, their fossil remains
>indicate that in one respect, the trilobites may have been superior to
>current living animals.  They had, in principle, perfect vision:  They
>possessed the most sophisticated eye lenses ever produced by nature."
>
>Shawver describes a discovery by Riccardo Levi Setti of the University
>of Chicago and the Fermi Institute, who realized that lenses of a
>certain class of trilobites were nearly identical to aspheric aplanatic
>lenses (lenses which minimize spherical aberration).  Levi Setti
>arrived at the conviction that "trilobites had solved a very elegant
>physics problem and knew about Fermat's principle, Abbe's sine law,
>Snell's laws of refraction and the optics of birefringent crystal."
>(This is quoted from his book _Trilobites_.) Of course Levi Setti is
>speaking very loosely when he talks about trilobites "knowing", but
>we'll pass over that, since evolutionists allow each other to talk
>this way.  The important point is that these are rather interesting
>structures.  The article further quotes:  "'Nature has developed a
>process of optimization, which in this case, produced these incredible
>sophisticated shapes,' says Levi Setti.  'It didn't happen by
>accident.  It proves that evolution can produce this kind of thing
>... the lenses look like they were designed by a physicist.'"

At the risk of exposing my limited knowledge about trilobites, I will
venture a few comments.

At this point, evolution directs me to ask several new questions.  It
would seem, that some powerful selection criteria may be the answer to
the highly developed eyes of the trilobite.  Not knowing a heck of a lot
about trilobite habits, offhand I would ask such questions as:

  1.  What do the trilobites eat?  If they feed on microscopic or near
      microscopic organisms, it could be that trilobites with better
      eyesight had better chances of finding food.

  2.  What hazards/predators/etc. were trilobites succeptible to?  Perhaps
      they needed special eyesight with profound depth perception and 
      correction to more effectively differentiate minute bits of food
      from minute bits of poisonous materials or some such thing.

  3.  What was their environment like?

  4.  What was their reproduction like?

  5.  etc. etc.

In other words, a highly developed trilobite eye leads me to explore
potential environmental and behavioral effects that may have been responsible
for a high selection criteria for very good eyesight.  The notes about 
'knowing' about Fermats theorem, etc.  are totally bogus arguments designed
to make the discovery LOOK like it was designed by a physicist by comparing
it with work of real physicists.  You can use that type of argument on 
anything.  If I throw a ball up in the air and it bounces on the ground
several times, do you assume that I am an expert in kinetic energy, 
gravity, etc.? (poor analogy I know)

>Keeping these things in mind, thee are some questions that must be
>asked:
>
>In what sense are these eyes "half-developed"?

In the sense that they may be on the way to being even more acutely
developed eyes, or eyes with different characteristics more useful
in a different environment.  The fact that they didn't evolve
any more dosen't mean they were 'fully evolved' as there is no
such thing as 'fully evolved'.  Perhaps the next phase could
have been a regression to a simpler eye if the highly developed
eye became less useful. 

>What are (were) they developing toward/from?

Not knowing much about trilobyte phylogeny, I can't really venture
much of an answer on the from, and as for the toward, see above. 

>Remembering that these were fairly early organisms, what sort of
>phylogeny shall one construct to show the development of these
>structures?

I'm not in a position to venture a guess, as I know effectively zip
about what current knowlege of trilobite phylogeny is.  I have no reason
to believe that there was not some sort of logical progression though,
an particularly not in exchange for a 'God magic' alternative.

>Yes, it is true that some organisms have *very* simple eyes.  But some
>early organisms have very unsimple eyes.  So statements about
>half-developed and simple eyes don't show much *unless* the line of
>descent is demonstrated.

Well, I don't know about that.

It isn't hard to see how a small organism who develops
a single light sensitive cell and when using it to move toward the light
encounters more food (algae perhaps?) might tend to survive better.  And
later, an organism with several such cells could begin to form some
rudimentary pattern recognition that might allow it to detect sudden
movements (of predators perhaps) or single out preffered food specimines
etc.

I remember an AI program I fooled around with once.  It was a very simple
pattern recognition program.  Over time, it would learn to recognize
one of 8 basic shapes.  Basically, the input was provided as a string
of bits that represented a simple 4x4 cellular array representation of
the pattern.  The input array was given to a series of 'citizens' who
'voted' on what they thought the correct answer was.  After voting,
each citizen's future votes were weighted based on the correctness
of their vote.  After being fed the prospective patterns and voting
for several 'generations' the citizenry became quite accurate at detecting
all the basic shapes, even imperfect ones.  The entire process was quite
rudimentary.  It is easy for me to see that the 'citizens' could be 
neurological-type cells using a 4x4 array of light sensitive cells as
input.  Initially, perhaps there was only a single neruon connected
to a single light sensitive cell.  As duplicate neuron-cell combinations
arose, the neruons could have infuenced each other to the point of 
becoming a simple system such as described above.  This program
by the way, uses the AI technique: simulated evolution.  Through
'natural selection' the citizenry 'evolve' into an efficient pattern
recognition mechanism that can conceivably be extended to a highly
complicated 'eye'.  Perhaps in the animal, later a clear protective
membrane may arise that eventually becomes some sort of lens.   If you
take it step by step, it is not hard to follow such buildup of complexity.
In the case of the trilobite, perhaps this animal had considerably more
reason to develop a relatively sophisticated eye then other animals have.
It is no reason to think that it couldn't have occured naturally given
enough time and the right conditions.

>Paul DuBois     {allegra,ihnp4,seismo}!uwvax!uwmacc!dubois        --+--

By the way, while we are talking about the 'argument of design',
I have a challenge for the creationists:

      Give me an example of something that WASN'T designed.

Keith Doyle
#  {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd