dubois@uwmacc.UUCP (Paul DuBois) (05/17/85)
Some statements have been made in this newsgroup recently that seem to me somewhat reckless. Ron Kukuk posted the following: >> 10. All species appear perfectly developed, not half >> developed. They show design [a]. There are no examples of >> half-developed feathers, eyes [b], Which prompted these two replies: > [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. 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.) But perhaps before they try, I think that such statements can be rendered implausible by examples that illustrate the difficulties of such constructions. I present such an example below. The astronomers on the net ought to find this interesting. --- 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." (The "in principle" is because the nervous system is what does the actual "seeing". It doesn't do much good to have a perfect eye if you are blind, for instance.) 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.'" One gets the impression that Levi Setti was impressed. Noteworthy is the statement that the eyes not happening by accident is proof of evolution. Design is evidence of no designer. I suspect that more reserved evolutionists would regard this as a rash statement. Levi Setti seems to have fallen into the curious mode of thinking in which the greater the sophistication of a structure, the stronger is the evidence that is shown for evolution. The more unlikely something is to have been produced, the "fact" that it did evolve shows how every powerful evolutionary processes are. If you can put yourself into the position of the creationist for a moment, you will begin to understand how ludicrous this seems to us. Well, anyway. It is not only the shape of the lenses that is remarkable, but also their structure. The remark by Levi Setti about solving a problem involving birefringent properties can be clarified by the following remarks. "The remarkable eyes of trilobites". Science News, 103(10), 10 Mar 1973, p154. "The eyes of trilobites, small, extinct arthropods of the Paleozoic era, have been found to possess sophisticated, glass-like lenses capable of producing relatively clear images over a wide depth of field. "The lenses owe their remarkable properties to their impregnation with the mineral calcite, specifically calcite with its crystal structure arranged so precisely as to produce the optical properties of glass." It should be noted that no known arthropod living today possesses similarly sophisticated visual structures. Kenneth M Towe, "Trilobite Eyes: Calcified lenses in vivo". Science, 179, 9 March 1973, 1007-1009. Towe studied two different trilobites: Phacops Rana - Devonian era Isotelus gigas - Ordivician era "As a highly birefringent mineral, calcite has a double refraction so pronounced that it is often used to illustrate the phenomenon. However, light passing in the direction of the _c_-axis (optic axis) is not doubly refracted and the mineral behaves isotropically with an index of refraction of 1.486. It is only in this special orientation that a lens made of calcite would be able to produce an image free of a doubling effect. Thus, the individual lenses of the schizochroal eye of _Phacops_ and the facets of _Isotelus_ are constructed of calcite so precisely oriented crystallographically that they behave as if they were made of glass. This unique crystallographic orientation, which is reproducible from specimen to specimen, cannot be considered an accidental postmortem or secondary replacement by calcium carbonate. Such a consistent and selective preferred orientation can only be due to a process of biomineralization. The calcite lenses must have been present during the life of the animals" [p1009]. --- Keeping these things in mind, thee are some questions that must be asked: In what sense are these eyes "half-developed"? What are (were) they developing toward/from? Remembering that these were fairly early organisms, what sort of phylogeny shall one construct to show the development of these structures? 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. -- | Paul DuBois {allegra,ihnp4,seismo}!uwvax!uwmacc!dubois --+-- | "Some trilobites had large eyes to enable them | to escape from their creditors more easily."
sidney@linus.UUCP (Sidney Markowitz) (05/18/85)
In article <1091@uwmacc.UUCP> dubois@uwmacc.UUCP (Paul DuBois) writes: > >Some statements have been made in this newsgroup recently that seem to >me somewhat reckless. Ron Kukuk posted the following: > >>> 10. All species appear perfectly developed, not half >>> developed. They show design [a]. There are no examples of >>> half-developed feathers, eyes [b], > >Which prompted these two replies: > >> [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. > >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.) Sonntag and Doyle's statements both contain the fallacy of accepting the fallacy in Kuluk's posting. When the pamphlet he's quoting says "All species appear perfectly developed, not half developed," there is no definition given for degree of development. One possibility is subjective. But then, a creationist could look at the simplest amoeba and say "There is a perfectly developed amoeba, each part perfectly developed for its role as part of an amoeba," and that would be an unarguable matter of opinion. An alternative definition of degree of development could be that "fully developed" means functional. In that case, evolutionary theory does not necessarily predict "half developed" eyes -- It predicts a series of "fully developed" (i.e. functional) structures that develop from one to another. An example is jaw bones becoming hearing apparatus, each step being a functional *something*. In one respect Doyle's statement is accurate -- There is a way of looking at species in which they all seem half-developed, if you are perceiving them as stages in an evolutionary series. This is the converse of the way they would seem if you are perceiving species as self contained, functional entities (or creations). The point is that such a ssubjective term can't be validly used to support any side of an argument. [you then quote the following article:] >Lisa J Shawver, "Trilobite eyes: An impressive feat of early evolution". >Science News, 105(5), 2 Feb 1974. > >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. Of course the previous statement is anything but passing over that, but I'll let you get away with such a cheap-shot debating tactic since you gave Setti that leeway :-) Actually, there is an important aspect to the loose phrasing that you pointed out. It sets an informal tone to the article. Setti was apparently not thinking in terms of presenting a rigorous argument that would have to stand up against the criticisms of creationists. I think he is assuming evolutionary theory being accepted by the reader. In fact, as you say... >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.'" > >One gets the impression that Levi Setti was impressed. Noteworthy is >the statement that the eyes not happening by accident is proof of >evolution. Not exactly. He said it was proof that evolution can produce such a thing. Setti was assuming evolution as a given, and saying he was impressed by what it produced. His saying that it didn't happen by accident is noteworthy for a different reason -- It points out what may be a fundamental difference between your thinking and that of a scientist. He looks at the actions of natural laws intersecting to bring about such an elegant effect and says something like "It's not an accident -- There's a cause and effect *reason* why it came out that way." You don't seem to accept cause and effect as enough of a reason for something complicated or precise to occur. You seem to require intelligent direction and purpose. Although I still haven't figured out why your concept of God isn't capable of creating laws of nature that mesh so well that a processes can be set in motion that lead to human minds and trilobite eyes. >Design is evidence of no designer. I suspect that more >reserved evolutionists would regard this as a rash statement. It's as rash as "design is evidence of a designer." The fallacy is that the word "design" implies a designer by definition. But the correct terms here are "complexity" and "organization", which are not so obviously evidence of a designer (as in the example of a snowflake). Complexity and organization are also not evidence for no designer, but as I pointed out, Setti is not claiming that this is proof of evolution -- he says that this is proof of the "neat" stuff that evolutionary processes can produce. Setti's statement is trivially true -- given his assumption of evolution. It doesn't really prove anything, but is an expression of his sense of aesthetics regarding nature, which, after all, is the point of his article. I'll skip your continuation along the same lines and the quotes describing details of the trilobite eyes, and go on to your questions: >In what sense are these eyes "half-developed"? > >What are (were) they developing toward/from? As I said above, the phrase "half-developed" is not a good one, as it is difficult to come up with a reasonable objective definition. The concept of "developing toward/from" is misleading, too. Please remember, Paul, that while you may think in terms of an anthropomorphic God with a pre-arranged master plan, evolutionary theory does not ascribe equivalent pre-organization to the evolutionary processes. In evolutionary terms you can only say that a species evolved from and towards something in the sense that you can describe a sequence with causal, temporal ordering. And if no such sequence exists, e.g., if trilobites were evolutionary dead ends, then it makes no sense to ask what trilobite eyes were developing towards. The answer to your question then, would be in the fossil record. I'll leave it to someone with more knowledge of paleontology to answer what is supposed to be the ancestors of the trilobite. Though I do have a further comment about that below... >Remembering that these were fairly early organisms, what sort of >phylogeny shall one construct to show the development of these >structures? > >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. One point that should be mentioned -- The trilobite eyes may very well represent an evolutionary dead end in an important way. The trilobite may represent the result of steady improvement in the optics of the lens. But as the original article pointed out, vision is a result of the nervous system, not the lens. We have a less perfect lens, optically, but a complex vision system in nerves and brain that can adapt to a wide range of variation produced by light and lenses. There's a fallacy in attempting to impose our own sense of aesthetics or suitability on nature (or God, if you prefer), when the reality of what it actually does is the final arbiter. -- Sidney Markowitz ARPA: sidney@mitre-bedford UUCP: ...{allegra,decvax,genrad,ihnp4,philabs,security,utzoo}!linus!sidney
js2j@mhuxt.UUCP (sonntag) (05/20/85)
Paul Dubois quoting some reliable sounding source: > > "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." > Now just hold on here for a minute. When we asked y'all why you were always using arguments against evolution instead of producing evidence which support creationism, you said it was because there were no other reasonable alternative theories, so debunking evolution was the same as advancing creationism. Well, I'm not sure I buy that 'no other reasonable alternative' stuff, but suppose I do, just for the sake of argument. If this is the framework of your case for creationism, it stands to reason that in debunking evolution *YOU CANNOT USE ARGUMENTS WHICH DIRECTLY OR IMPLICITLY CONTRADICT YOUR MODEL OF CREATIONISM*. Sorry for yelling there, but I wanted to get your attention. There are a few variations of the creationist models which aren't contradicted by 300 million year old tribolite fossils, of course, but the one issued by the ICR (which Paul said he agreed with, I think. (correct me if I'm wrong on that, Paul.)) specifically included the 'young earth' bit. One last time for clarity: If you're trying to support creationism by debunking evolution, you can't use evidence which also debunks creationism. Get it? -- Jeff Sonntag ihnp4!mhuxt!js2j "Time has passed, and now it seems that everybody's having those dreams. Everybody sees himself walking around with no one else." - Dylan
beth@sphinx.UChicago.UUCP (beth d. christy) (05/24/85)
[keep :-)ing] In Message <1091@uwmacc.UUCP> dubois@uwmacc.UUCP (Paul DuBois) writes: >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." > >(The "in principle" is because the nervous system is what does the >actual "seeing". It doesn't do much good to have a perfect eye if you >are blind, for instance.) > >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.'" > >One gets the impression that Levi Setti was impressed. Noteworthy is >the statement that the eyes not happening by accident is proof of >evolution. Design is evidence of no designer. I suspect that more >reserved evolutionists would regard this as a rash statement. > >Levi Setti seems to have fallen into the curious mode of thinking in >which the greater the sophistication of a structure, the stronger is >the evidence that is shown for evolution. The more unlikely something >is to have been produced, the "fact" that it did evolve shows how every >powerful evolutionary processes are. If you can put yourself into the >position of the creationist for a moment, you will begin to understand >how ludicrous this seems to us. > >[more stuff detailing how terrific these particular eyes were -bdc] > >It should be noted that no known arthropod living today possesses >similarly sophisticated visual structures. > >[ditto -bdc] > >Keeping these things in mind, thee are some questions that must be >asked: > >In what sense are these eyes "half-developed"? > >What are (were) they developing toward/from? > >Remembering that these were fairly early organisms, what sort of >phylogeny shall one construct to show the development of these >structures? > >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. > >Paul DuBois {allegra,ihnp4,seismo}!uwvax!uwmacc!dubois --+-- Those eyes were developing into fossils for us to find. They were "half-developed" because at the time they existed there wasn't anyone who seriously questioned evolution, and hence they weren't yet useful as evidence to prove it. Now there are, and now *they* are. Now I have a question for you: Given that there are thousands of species with eyes, and given that a designer clearly had a concept and an implementation of such a perfect eye, *why* is there such vast diversity in the types and relative quality of eyes? Why didn't the designer recognize a good thing when s/he had it and stick with it? The "curious mode of thinking" that Levi Setti has fallen into is probably a result of taking things in context - something that often *does* confound creationists on this net. He recognized that there were an *awful lot* of comparitively imperfect eyes (dare I say "imperfectly designed" eyes?!), and appreciated finding a single, isolated counter example. Simple as that. -- --JB "The giant is awake." Disclaimer? Who wud claim dis?