David Campbell wrote:
>
> >Could you please include:
> >
> >1) Development of biochemical processes step by step showing adaptive
> >utility of each step.
> >Photoactivity must be connected to a set re-set mechanism and must be
> >connected to the
> >neorological system in some fashion.
>
> Explaining this would require a lot of patience on your part, as someone
> has to find out what all the biochemical processes are in the first place,
> and I have to read them as well as finish my dissertation and get a job. I
> am not a biochemist, so I do not know what is known about all of these.
********
Nothing, absolutely nothing. There is no explaination presented about
how this alleged gradualism developed. Only a school childs drawing.
*********
I
> believe there are some ideas on the evolutionary precursors of
> photosensitive pigments, but do not remember any detail.
************
You do not remember any details because you were never given any.
***********
I can describe
> the biochemical evolution of primate red-green color vision, if that would
> be of interest.
***********
Any I would like to see some evidence to support it.
*********************
>
> >From a morphological point of view, any sort of eye from a single
> photosensitive cell on up is useful.
**************
Mophology involves making pencil drawings which ignore the real details.
Take a pencil and draw an airplane. Now, the real question is the shape
of the wing for lift and the weight to strength ratios and the specifics
of thrust and drag. The pencil drawing may look appealing but is
without content and certainly not an existence proof that the drawing
can fly.
***************
The wide range of eye types in living
> and fossil organisms suggests that there are quite a few genetic
> combinations that would be functional intermediates.
>
> For the most simple eye function, all that is needed is a connection to the
> appropriate response function. A brain is not necessary, just a neuron.
> For example, the ark shell in the aquarium that closed its valves when I
> walked past diid not have a brain. It did have simple eyes, enabling it to
> detect a moving shadow, and some sort of connection to the adductor muscles
> to send the message, but no image processing. Even its eyes are well ahead
> of the simplest.
>
> >Also, I want to know the purported time frame for these mutations. That
> >is,
> >according to the geological record, every so often a nasty rock from
> >space kinda messed
> >things up.
>
> The oldest fossil eyes I know of are on Early Cambrian arthropods. These
> are moderately well-developed, suggesting older eyes existed. As soft
> parts, they do not necessarily fossilize well. The genetic mechanism
> builds on similar precursors in all bilaterian animals, but it is unknown
> whether this means that the ancestor of all bilaterians had very primitive
> eyes or whether it simply had a gene useful towards that end, which evolved
> in parallel in different groups.
>
> Complex eyes have evolved several different times.
********************
How about being accurate.
"Complex eyes appear in the follil record at several different times.
Those who prefer to see evolution as the mechanism believe that this was
due to evolution and those who see a designer prefer to see his action
in this."
******************
They also have been
> lost multiple times, making it difficult to tell exactly when they evolved
> in what group. Scallops have eyes but the glass scallops do not. However,
> glass scallops are predominantly deep water species, where eyes are not
> very useful. No fossil soft parts are known for scallops, so it is not
> sure whether scallops evolved eyes after they separated from glass scallops
> or whether the ancestral form had eyes and glass scallops lost them. Thus,
> the timing of the evolution of eyes in scallops is not very clear.
>
> Overall, the timing of eye evolution could have, as a maximum, between a
> billion and half a billion years.
******************
I did not speak of timing as to when. I spoke to the rate of
development giving the amount of time available. I am looking for a
solid rate of development times time equals organ type arguement.
*****************
Groups such as the scallops have
> apparently evolved less complex eyes in a shorter period of time.
>
> >as all
> >> the intermediate steps are useful,
> >*********
> >
> >WOW. This is a great assertion. Want to support it with someting.
> >Please, fill us in.
>
> Again, I was thinking of the morphology. Even rudimentary eyes are useful
> for any organism not always in total darkness. If you can see something,
> you can respond to it. If you can see more clearly and have the mental
> ability, you can respond more precisely.
>
> >Reduction in the utility of an existing function is not very
> >convincing. You
> >still have a great processing unit collecting even mitigated
> >information.
>
> My point was not clear. If something evolved to the point of seeing as
> well as I do without glasses, it would be able to get a lot of informaiton
> from that. If it evolved better vision than that, it could get more
> information without having to hold things within a few inches of its eyes.
>
> > Really, can you count the bytes of information in
> >the eye
> >for example and then estimate the number of bytes of information that
> >could
> >be generated per generation and then the number of generations.
> >Something
> >to hang this on, just something.
>
> A rough number of generations would be a few hundred million.
***********
Assuming I accept this at face value, now do a calculation with mutation
rate, subtract the bad mutations, and give us a number for the potential
additional information rate per year.
Bert M
*****************
David C
Your assumptions and insertion of evolution through gradualism are
lacking of any specifics. What seems true to me is that the animals
lived in great antiquity and different ones at different times. The
real action as at the molecular level and at the genetic level.
Morphology contains very very few bytes of information. Simply saying
"Well, this proteye MUST have appeared and then MORE COMPLEX eyes
appeared and then connecting the dots with "assumed evolution" is
without support. Give me some content. Design the airplane--weight,
balance, drag, thrust, lift, etc. and then we can at least asses the
theory.
Bert M.
>
> David C.
This archive was generated by hypermail 2b29 : Thu Jan 13 2000 - 14:07:15 EST