Fascinating stuff.
The Evolution of the Eye.
by whereami 38 Replies latest jw friends
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wannabefree
The eye, what a marvel of creation! Simply amazing.
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leavingwt
The WT points to the eye as evidence of an intelligent designer. They are willfully ignorant.
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Evolution of the Eye:
When evolution skeptics want to attack Darwin's theory, they often point to the human eye. How could something so complex, they argue, have developed through random mutations and natural selection , even over millions of years?
If evolution occurs through gradations, the critics say, how could it have created the separate parts of the eye -- the lens, the retina, the pupil, and so forth -- since none of these structures by themselves would make vision possible? In other words, what good is five percent of an eye?
Darwin acknowledged from the start that the eye would be a difficult case for his new theory to explain. Difficult, but not impossible. Scientists have come up with scenarios through which the first eye-like structure, a light-sensitive pigmented spot on the skin, could have gone through changes and complexities to form the human eye, with its many parts and astounding abilities.
Through natural selection, different types of eyes have emerged in evolutionary history -- and the human eye isn't even the best one, from some standpoints. Because blood vessels run across the surface of the retina instead of beneath it, it's easy for the vessels to proliferate or leak and impair vision. So, the evolution theorists say, the anti-evolution argument that life was created by an "intelligent designer" doesn't hold water: If God or some other omnipotent force was responsible for the human eye, it was something of a botched design.
Biologists use the range of less complex light sensitive structures that exist in living species today to hypothesize the various evolutionary stages eyes may have gone through.
Here's how some scientists think some eyes may have evolved: The simple light-sensitive spot on the skin of some ancestral creature gave it some tiny survival advantage, perhaps allowing it to evade a predator. Random changes then created a depression in the light-sensitive patch, a deepening pit that made "vision" a little sharper. At the same time, the pit's opening gradually narrowed, so light entered through a small aperture, like a pinhole camera.
Every change had to confer a survival advantage, no matter how slight. Eventually, the light-sensitive spot evolved into a retina, the layer of cells and pigment at the back of the human eye. Over time a lens formed at the front of the eye. It could have arisen as a double-layered transparent tissue containing increasing amounts of liquid that gave it the convex curvature of the human eye.
In fact, eyes corresponding to every stage in this sequence have been found in existing living species. The existence of this range of less complex light-sensitive structures supports scientists' hypotheses about how complex eyes like ours could evolve. The first animals with anything resembling an eye lived about 550 million years ago. And, according to one scientist's calculations, only 364,000 years would have been needed for a camera-like eye to evolve from a light-sensitive patch.http://www.pbs.org/wgbh/evolution/library/01/1/l_011_01.html
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leavingwt
Zoologist Dan-Erik Nilsson demonstrates how the complex human eye could have evolved through natural selection acting on small variations. Starting with a simple patch of light sensitive cells, Nilsson's model "evolves" until a clear image is produced. Examples of organisms that still use the intermediary forms of vision are also shown. From Evolution: "Darwin's Dangerous Idea"
http://www.pbs.org/wgbh/evolution/library/01/1/quicktime/l_011_01.html
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The Scotsman
To say the eye evolved is laughable......
"""If God or some other omnipotent force was responsible for the human eye, it was something of a botched design."""
LOL........
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hamsterbait
Scotsman -
Are you mocking the argument in favor of the eye evolving, or quoting statements above and laughing at THEM?
I am well satisfied that the eye evolved - even moreso than the ridiculous moral code of the Jews.
In terms of design and efficiency, the human eye is not the best. It is the work of a tinkerer. The pineapple of Gods creation has eyes less well designed than those of unreasoning animals.
HB
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whereami
Come on hamsterbait, we all know the eye just popped into existence. It's just perfect.
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The Scotsman
I have just picked up my 10 megapixel camera and I was just thinking to myself - "Why is this not a 15 megapixel?
The designer clearly made a botched job of the 10 megapixel camera - because its not the best.
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Caedes
I have just picked up my 10 megapixel camera and I was just thinking to myself - "Why is this not a 15 megapixel?
The designer clearly made a botched job of the 10 megapixel camera - because its not the best.
But then presumably the designer of your camera isn't claiming to be an omniscient, omnipotent creator of the universe who demands worship. Also, your camera engineer presumably hasn't left in fundamental design flaws he has fixed in other cameras he has designed. Other than that a spot on analogy.
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The Scotsman
But then presumably the designer of your camera isn't claiming to be an omniscient, omnipotent creator of the universe who demands worship
No - the designer is just an intelligent human (or group of humans) who design and construct cameras. If not for these humans digital cameras would not exist -or would they have evolved to? Intelligence existed first before the camera (that's kinda my point).
Also, your camera engineer presumably hasn't left in fundamental design flaws he has fixed in other cameras he has designed.
Who decides if something is a flaw or not. People point to other living things that clearly have better eyesight than humans as proof "somehow" that God bungled human eye sight. To live my life I do not need eagle eye vision or radar sight or night vision - my eyes are just fine for me.
And yes. eyes are not perfect - no part of a human being is perfect. I am sure I read that in a book somewhere..............
