However, the origins of cute bunnies is a topic covered by the TOE!
Check here for other questions: The Official God F.A.Q.
Posted on 11/03/2004 5:11:47 PM PST by general_re
Darwin's greatest challenge tackled
The mystery of eye evolution
Researchers provide concrete evidence about how the human eye evolved
When Darwin's skeptics attack his theory of evolution, they often focus on the eye. Darwin himself confessed that it was 'absurd' to propose that the human eye, an 'organ of extreme perfection and complication' evolved through spontaneous mutation and natural selection. But he also reasoned that "if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist" then this difficulty should be overcome. Scientists at the European Molecular Biology Laboratory [EMBL] have now tackled Darwin's major challenge in an evolutionary study published this week in the journal Science. They have elucidated the evolutionary origin of the human eye.
Researchers in the laboratories of Detlev Arendt and Jochen Wittbrodt have discovered that the light-sensitive cells of our eyes, the rods and cones, are of unexpected evolutionary origin they come from an ancient population of light-sensitive cells that were initially located in the brain.
"It is not surprising that cells of human eyes come from the brain. We still have light-sensitive cells in our brains today which detect light and influence our daily rhythms of activity," explains Wittbrodt. "Quite possibly, the human eye has originated from light-sensitive cells in the brain. Only later in evolution would such brain cells have relocated into an eye and gained the potential to confer vision."
The scientists discovered that two types of light-sensitive cells existed in our early animal ancestors: rhabdomeric and ciliary. In most animals, rhabdomeric cells became part of the eyes, and ciliary cells remained embedded in the brain. But the evolution of the human eye is peculiar it is the ciliary cells that were recruited for vision which eventually gave rise to the rods and cones of the retina.
So how did EMBL researchers finally trace the evolution of the eye?
By studying a 'living fossil,' Platynereis dumerilii, a marine worm that still resembles early ancestors that lived up to 600 million years ago. Arendt had seen pictures of this worm's brain taken by researcher Adriaan Dorresteijn [University of Mainz, Germany]. "When I saw these pictures, I noticed that the shape of the cells in the worm’s brain resembled the rods and cones in the human eye. I was immediately intrigued by the idea that both of these light-sensitive cells may have the same evolutionary origin."
To test this hypothesis, Arendt and Wittbrodt used a new tool for today’s evolutionary biologists – 'molecular fingerprints'. Such a fingerprint is a unique combination of molecules that is found in a specific cell. He explains that if cells between species have matching molecular fingerprints, then the cells are very likely to share a common ancestor cell.
Scientist Kristin Tessmar-Raible provided the crucial evidence to support Arendt's hypothesis. With the help of EMBL researcher Heidi Snyman, she determined the molecular fingerprint of the cells in the worm's brain. She found an opsin, a light-sensitive molecule, in the worm that strikingly resembled the opsin in the vertebrate rods and cones. "When I saw this vertebrate-type molecule active in the cells of the Playtnereis brain – it was clear that these cells and the vertebrate rods and cones shared a molecular fingerprint. This was concrete evidence of common evolutionary origin. We had finally solved one of the big mysteries in human eye evolution."
Source Article
Ciliary photoreceptors with vertebrate-type opsins in an invertebrate brain.
D. Arendt, K. Tessmar-Raible, Snyman, Dorresteijn, J. Wittbrodt
Science. October 29, 2004.
Behold the power of Salamanders!
[LOL!]
Of course evolution doesn't explain the origin of life. It's not supposed to. It is a theory about the changes that life underwent after it formed. There are scientific theories about the origin of life, however. These have much less convincing evidence in their favor than does evolution. Scientists are still working on this issue. On the origin of the universe, this too has nothing to do with whether evolution is true or not. The big bang theory exists to explain the way the universe developed. There is a good deal of solid evidence to support this theory just as there is for evolution. It strikes me that neither evolution or big bang theories are incompatible with creationism, however. Is it not possible that God created the universe via the big bang and then created life (whether via a special act of creation or abiogenisis or any other method is irrelevant), and then created the mechanism of evolution to allow for the wide diversity of life we see now? Could not "let there be light" refer to a big bang? (In the earliest stages of the universe, according to the big bang, light is all there is. Matter is created from the light) The Bible also gives the order of creation of types of life in essentially the same order as the theory of evolution predicts. Maybe the scientific theories and the Bible are consistent with each other. There is only one truth. If science and religion appear to contradict each other, the problem is with our understanding of either science, the Bible, or both.
Whooohooo! Back to science and evolution. :-)
Yeh, I got real tired of Kerry/Bush babble.
I have no problem with either theory, as long as they are not used to explain the origins of life or the universe, which is often the case.
Science is a very good way of trying to understand all that God has created. It is, however, a very ineffective way of disproving God's existence.
The origins of the universe is not a topic covered by the TOE.
Check here for other questions: The Official God F.A.Q.
I bet those bunnies would be delicious.
Thank you. I am convinced.
Odd. That wasn't supposed to happen.
Surely you jest?
Try "Finding Darwin's God" for a point by point analysis of Behe's argument. Behe made predictions about things science would never find due to unattainable complexity that had already been discovered before he published "Darwin's Black Box".
"Inadequate bench-checking", my old physics prof would have said.
As to why fish and amphibians can regenerate retinal cells, but people and rats can't, and chickens have only limited abilities to do so, my hypothesis is based on two suppositions: first, endothermic vertebrates (birds and mammals) either semi- or fully lost their regenerative abilities when they gained the advantage of warm-blooddedness (the same reason why we can't regenerate limbs the way reptiles and amphibians can). Secondly, mammals lost their ability to see in color because as nocturnal animals, it wasn't necessary; whereas birds, being primarily diurnal animals, kept color vision (primates, including mammals, regained their color cones when they returned to an active day life). Similarly, because mammal eyes didn't need the continual protection from intense visible and UV light, they may have completely lost the capacity for retinal regeneration.
You have no evidence at all that anything, anything at all, is "infinite, and therefore, always was and always will be" because in order to have this evidence you would have to be "infinite, and therefore, always existing and always will be" in order to gather enough evidence to prove and validate the premise. There is simply no way you can know this.
God created time for our benefit, but is not bound by His creation.
Begs the Question that you 'know' that God created time. There is no way you can know this. Where and how did you gain this knowledge? Assertion Without Proof.
The universe, on the other hand, had to have a beginning.
Again, how do you know this? The Universe "appears" to have had a beginning, but you cannot "know" this. Assertion Without Proof. Best Supposition, at best.
The question remains, if everything had a first cause, what was the first cause for God? Otherwise, everything didn't have a first cause, (because God didn't) and why choose God as not having a first cause rather than the Universe?
Faulty logic.
“Evolution Stories Are Subtle and Complex” – Truth or Euphemism? 10/29/2004
A worm brain has photoreceptors similar to those in humans. What does it mean? Elizabeth Pennisi in Science1 sets the stage, commenting on work by Arendt et al. in the same issue,2 “Ciliary Photoreceptors with a Vertebrate-Type Opsin in an Invertebrate Brain.” One might think this demonstrates common ancestry, but Pennisi explains that it’s not a simple evolutionary story:
Despite incredible variation in size and shape, eyes come in just two basic models. The vertebrates’ photoreceptor cells, typified by rods and cones, are quite distinctive from the invertebrates’. And although both use light-sensing pigments called opsins, the opsins are quite different in their amino acid makeup. For years biologists have argued about how these varied components came to be. Some insist that eyes evolved only once, despite this modern difference [sic]. Others have argued that optical structures evolved at least once in invertebrates and again in vertebrates. New data showing unexpected similarities between photoreceptors of a marine worm and humans add a new twist to this debate. Detlev Arendt and Joachim Wittbrodt, developmental biologists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, and their colleagues have found that in addition to its regular opsin pigment, the worm contains another one almost identical to the human’s. Their finding suggests that even the earliest animals had the makings of both vertebrate and invertebrate visual systems, and that some of the photoreceptor cells in the invertebrate brain were transformed over a series of steps into vertebrate eyes [sic]. Although some researchers are skeptical, others think the data are sound....
The research team thinks this “sheds new light on vertebrate eye evolution,” but the problem is that it pushes the origin of sight, a complex interaction of multiple functional parts, even farther back in time. Another problem is that the human-like opsin in the worm has been conserved (unevolved) for 500 million years, according to the standard evolutionary time scale:
Arendt and Wittbrodt jumped into the fray over eye evolution after Arendt noticed some odd cells in the brains of ragworms, a relic marine annelid species that’s been relatively unchanged for the past 500 million years. “We were surprised,” Arendt recalls, as these cells looked very much like rods and cones.
Further molecular and genetic studies showed that “Not only the morphology [outward appearance] but also the molecular biology of the two types of receptors was already set in our common ancestor” [sic], according to a French biologist. To put this new discovery into an evolutionary context, Arendt et al. had to invent a hypothetical ancestor even further back in time from the hypothetical ancestor of vertebrates and invertebrates, dubbed Urbilateria:
They go further to suggest that the two types likely [sic] arose [sic] in a predecessor of Urbilateria. In that organism, they speculate, the gene for one opsin and the genes to build the one type of photoreceptor cell were duplicated. The extra set of genes might have evolved [sic] into a different visual system: “We think both photoreceptor cells track back to one cell type,” [Joachim] Wittbrodt [one of the authors of the paper] says.
As the authors put it in conclusion, “The vertebrate eye thus represents a composite structure, combining distinct types of light-sensitive cells with independent evolutionary histories” [sic]. So although this proposal seems to favor those who argue for the single origin of eyes, it illustrates that “evolution stories are subtle and complex.”
1Elizabeth Pennisi, “Worm’s Light-Sensing Proteins Suggest Eye’s Single Origin,” Science, Vol 306, Issue 5697, 796-797, 29 October 2004, [DOI: 10.1126/science.306.5697.796a]. 2Arendt et al., “Ciliary Photoreceptors with a Vertebrate-Type Opsin in an Invertebrate Brain,” Science, Vol 306, Issue 5697, 869-871, 29 October 2004, [DOI: 10.1126/science.1099955].
“A likely story” can have opposite meanings depending on the tone of voice. Is the phrase, “subtle and complex” descriptive of a truth, or a euphemism for a dodge? Suppose you were a teacher, and your student’s story about the origin of his term paper, which was clearly a hodgepodge of plagiarisms from several internet sources, he described as “subtle and complex.” Suppose a politician described his flipflops over the years as being subtle and complex. Suppose your husband’s disastrous room addition project was defended with a story he said was subtle and complex. One thing is clear about this evolutionary story, as admitted by Pennisi: it is not simple and straightforward.
The PBS Evolution series tried to claim in 2001 that the eye followed a simple and straightforward progression from simple to complex, using the visual power of suggestion that a series of pictures of animal eyes in a progression from apparently simple to complex suggested an ancestral relationship. Evolutionists love the word “suggest”. Scattered similarities between distant organisms, all thriving in their own environments, all using highly-complex functional systems only “suggest” an evolutionary story when you have put yourself under Charlie’s spell and have opened yourself up to the power of suggestion. Snap out of it.
Read this evolutionary story with the wide-awake understanding that opsins are very complex proteins (see 10/01/2004 headline and Michael Behe’s Darwin’s Black Box, pp. 15-25). But their complexity alone is useless without even more complex organs and neurons that can interpret their responses. Evolutionists want to hypnotize us into the suggestion that stories relating worms to humans by common ancestry are scientific. Be a clear-headed judge of the evidence. When missing links have to be invented out of thin air, and when complex functions have to be presumed to have “arisen” [a miracle word] earlier than previously believed, the burden of proof is on the storyteller that the statement, “evolution stories are subtle and complex,” is not just pulling wool over the eyes.
[Crickets chirping ...]
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.