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What Birds See [evolution of the eye]
Scientific American ^ | July 2006 | Timothy H. Goldsmith

Posted on 07/03/2006 10:05:56 AM PDT by doc30

We humans customarily assume that our visual system sits atop a pinnacle of evolutionary success. It enables us to appreciate space in three dimensions, to detect objects from a distance and to move about safely. We are exquisitely able to recognize other individuals and to read their emotions from mere glimpses of their faces. In fact, we are such visual animals that we have difficulty imagining the sensory worlds of creatures whose capacities extend to other realms--a night-hunting bat, for example, that finds small insects by listening to the echoes of its own high-pitched call. Our knowledge of color vision is, quite naturally, based primarily on what humans see: researchers can easily perform experiments on cooperative human subjects to discover, say, what mixtures of colors look the same or different. Although scientists have obtained supporting information from a variety of other species by recording the firing of neurons, we remained unaware until the early 1970s that many vertebrates, mostly animals other than mammals, see colors in a part of the spectrum that is invisible to humans: the near ultraviolet. ...

(Excerpt) Read more at sciam.com ...


TOPICS: Culture/Society
KEYWORDS: bird; creationism; evolution; eye; ignoranttheocrats; kindastupid; ludditefundies; lyingforthelord; paganjunk; pavlovian; roadtohorseshitpaved; saganscience; youngearthcultists
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To: hosepipe
Thats not evolution its mutation... same with Darwins Finches..

Candidate for the insight of the century.

201 posted on 07/03/2006 6:56:03 PM PDT by js1138 (Well I say there are some things we don't want to know! Important things!")
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To: GourmetDan
And you are *assuming* that legs 'evolved' first and then were lost. It is much more consistent w/ observation that they were *created* first and then lost. Species losing function is easily observed. Species 'evolving' legs is not observed.

Two points. First, where is the evidence legs were created. Simple answer - there isn't any.

Second point. The presence of vesigal legs in snakes is not a degradation of information. A true degradation would be the lack of any leg like structures or associated anatomy. Snakes still have these components, but they are simply not developed into full legs. There was no real loss of information as demonstrated by the mere presence of vesigal structures. Genetically, the structures simply are regulated to stop growing at an earlier point. It is an illusion information is degraded or lost.

When you say that 'you have to look at the whole genetic heirarchial history', then you are imposing your *beliefs* on a set of evidence.

And about genetic sciences. That's rock solid stuff. There is no speculation. Only wishful thinking on the part of creationist types that cannot refute the clearly demonstrated genetic relationships between living things. Yopu are sticking your head in the sand and essentially saying that evidence, that is quantifiable facts, require belief. At this point, you are basically saying that you don't care what reality says, you chose NOT to beileve it. At that point, your credibility has diminished faster than a defense witness in the Dover ID case.Multiple species form a 'kind'. Dogs, coyotes and wolves are separate species but the same 'kind'. They can all interbreed. This is not counter to prevailing creationist.

So speciation is not enough to demonstrate evolution? Sounds like a moving bar to me. Once it has been shown that speciation has occurred in the lab, that does not become good enough. So evolution at the genus level is the next creationist bar? Cats and dogs are both mammals so a new genus between the two would still be a 'kind.'

The whole idea of 'kind' is so loosely based as to be laughable. You can't specifically define it but you use the term as it suits you. Even in biology, the terms species and genus are human labels based on human definitions. Nature doesn't care what we call things.

202 posted on 07/03/2006 7:43:52 PM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: GourmetDan; js1138
They are 'multiple, related lines of interpretation of evidence' because they are *all* based on the same initial assumption (i.e., that the explanation *must* be natural).

js1138, at this point, GourmetDan has shown he is anti-science since the very core of science functions on the assumption that reality is natural and not supernatural. That, GourmetDan, is why you rebel against reality. You wish to believe that there is a supernatural operating principle. TO argue in favor of a supernatural explanation is more primitive and more speculative than anything arguement arising from science. Science imposes restrictions where evidence is a requirement. Your belief system denies that.

203 posted on 07/03/2006 7:49:45 PM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: GourmetDan
You have trapped yourself. You can either admit that the 'evolutionary paradigm' is no different from the 'design paradigm' and 'explains everything' *or* you can provide evidence which is not explained by the 'evolutionary paradigm', in which case you are arguing against your own position.

Apparently you don't know the difference between falsifiable and falsified. All valid scientific theories are falsifiable, but they have not been falsified, that is, they are still held as viable.

The idea is to conceive of something that would falsify your theory. An example of a data point that would falsify ToE would be finding bones of modern humans and mammals mixed in the Precambrian geological layers. That means ToE is falsifiable. Those kinds of bones haven't been found in that layer. The ToE has not yet been falsified in that way.

Now, conceive of a scenario that would falsify ID. Unless the means and methods of the designer are known and can be predicted, I don't see how it can be falsified at all.

204 posted on 07/03/2006 7:52:20 PM PDT by stands2reason (ANAGRAM for the day: Socialist twaddle == Tact is disallowed)
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To: Lazamataz

I'm having trouble with that one myself.

Rooster or hen?


205 posted on 07/03/2006 7:54:44 PM PDT by eddie willers
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To: Mogollon

Yeesh. I try and try to stay out of these debates, but...

Pharmacodynamic tolerance is an acquired trait, not a hereditary one.

So you're really, really, wrong. Streptomycin resistance is caused predominantly by a hereditary mutation in the ribosomal S12 subunit gene. When the sensitive population was exposed to this drug, this mutation was strongly selected for as predicted by natural selection. Evolution in action.

But please, if you still disagree, by all means explain precisely how all that we've observed with regards to streptomycin resistance is consistent with pharmacodynamic tolerance.

Feel free to use references from the primary literature.


206 posted on 07/03/2006 7:56:11 PM PDT by staterightsfirst
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To: js1138
Interesting links. I only took a quick look at the first to get the ghist of the subject. This experiment does demonstrate that color preception is neurological since none of those colors are actually present on the disk. It may well be related to firing rate. Butthe important point is that the receptors, in conjunction with the neurology between the receptors and the brain's perception, are stimulated in such a way that color is perceived. Your brain really senses it, but it is an interpretation of data coming from the retina.

Based on what I know, the trick is to stimulate the cones in such a way that the brain perceives a given color. There are three types of cones, each with a different spectral response. I can easily imagine that, as the disk is spinning, the constrast line between the white and black would move across the retina as a front. Since the cones (receptors) are activating at slightly different times, because no two receptors are in the exact same location, then the brain perceives this phase difference as a different ratio between different receptors and color perception is generated. It is a very interesting illusion.

207 posted on 07/03/2006 7:59:59 PM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: doc30

The interesting thing is that (from my personal observation) the illusion of color is best under monochromatic light. If you can get a low pressure sodium vapor light, try it.

If the rotation of the disk is reversed, the colors swap -- red to blue, and vice-versa.


208 posted on 07/03/2006 8:03:39 PM PDT by js1138 (Well I say there are some things we don't want to know! Important things!")
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To: stands2reason

"You think highly of Christians who think that only Christians are conservatives?'

Forgive me, but I have no idea what you are talking about.


209 posted on 07/03/2006 8:20:22 PM PDT by Robwin
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To: Skooz
You want all white Christians who believe in creation to become Democrats?

Well they used to be.

210 posted on 07/03/2006 8:27:37 PM PDT by Oztrich Boy (No Christian will dare say that [Genesis] must not be taken in a figurative sense. St Augustine)
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To: b_sharp
Now you know why mice are so prolific.

Great point.
211 posted on 07/03/2006 8:35:38 PM PDT by microgood (Truth is not contingent)
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To: stands2reason

I didn't say you wrote that, I was posting to sentis. Sorry for your misunderstanding that it was directed at you. I think sentis may have issues with Christians, in general.

I'm happy to debate or discuss, but it's difficult to have an intelligent conversation when ad hominem attacks or witty rejoinders like "BS" are the preferred means of discourse.

Here's just some of what sentis wrote:

To: Central Scrutiniser
I am always wishing those same people would go on over to hang with their intellectual equals in the democrat party.


50 posted on 07/03/2006 10:56:30 AM PDT by Sentis

To: Skooz
Nope just the intellectual giants in the Christian camp that confuse conservatism with their religion. We dont need them and they generally turn out to be knuckle dragging racists too and so fit much better with the libs.

54 posted on 07/03/2006 11:01:13 AM PDT by Sentis


Trust me you would fit right in. I suggest anyone that thinks that atheists, hindus, buddists, blacks, hispanics or others aren't fit to be conservatives stop posting here and go where your wanted.

61 posted on 07/03/2006 11:08:01 AM PDT by Sentis


I said in a previous post that Christians are not exclusionary, nor racist. And there are many that contribute thoughtful postings to Free Republic. And I do not "confuse" my Christianity with conservativism - morals and ethics, including Christianity, are an integral part of conservative thought.

Blessings,


212 posted on 07/03/2006 8:43:03 PM PDT by Wicket (God bless and protect our troops and God bless America)
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To: js1138

That would be consistent with the geometric factor I mentioned. You would be reversing the phase of the activation of the photoreceptors involved, hence different, evem opposite colors would be expected.


213 posted on 07/03/2006 8:44:04 PM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: stands2reason
No, he didn't. I understood what he was saying, why can't you?

I think you understand what you think he's is conveying, not what he is actually saying.

You quoted: "Nope just the intellectual giants in the Christian camp that confuse conservatism with their religion."

I suppose, on some planet somewhere, the phrase "the intellectual giants in the Christian camp that confuse conservatism with their religion" can be translated as "the neo-Nazis who wish to exclude all non-whites, non-Christians, non-Creation believing, non-male, bla bla bla..." But, not on this one. If that is what he meant, he could have just said so sans the code words.

I was a flaming liberal before I became a Christian. After becoming a Christian, I examined my core beliefs deeply and, within a year or two, became a committed conservative.

For that reason, I could also be considered a Christian who confuses conservatism with my religion, because I am a conservative because of my religion.

Then, your buddy went off the deep end with personal insults and some pretty bizarre accusations that have no basis in reality.

I don't see how you could mistranslate that "nope".

The "nope" is not in question. His comments after the "nope" lead to a different conclusion than what you draw.

Yet you continue to misconstrue Sentis' statement.

I translated what he said verbatim. Called him on it, and was pronounced a Nazi because I dared disagree with his hatred.

214 posted on 07/03/2006 8:55:46 PM PDT by Skooz (Chastity prays for me, piety sings...Modesty hides my thighs in her wings...)
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To: doc30; js1138
There was a thread, right here on FR "Looking For Madam Tetrachromat." Seems to be on topic. I thought it was interesting at the time.
215 posted on 07/03/2006 9:01:35 PM PDT by Gumlegs
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To: Gumlegs

Great detective work. Here's something cool:

"Those findings have shown that the genetics underlying color vision are surprisingly variable, even within the narrow range regarded as normal. "The variety in photopigment genes in people with normal color vision is enormous," Dr. Neitz reports. "It's enormous."

This corresponds to my experience with colorblind people, including my son. They are not pure in any theoretical sense. They can see more colors in daylight than indoors.


216 posted on 07/03/2006 9:14:16 PM PDT by js1138 (Well I say there are some things we don't want to know! Important things!")
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To: js1138
This corresponds to my experience with colorblind people, including my son. They are not pure in any theoretical sense. They can see more colors in daylight than indoors.

I can't comment on the colorblindness issue from personal experience -- my color vision has always been normal -- but I do know that since I've needed glasses for reading, more light means less reliance on the glasses. For quite a while at first, I was still able to read without them if I was in bright sunlight.

217 posted on 07/03/2006 9:32:30 PM PDT by Gumlegs
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To: wbmstr24
See posts 26 & 33 none of the other faithful would face up to the scientific method to support their beliefs.
218 posted on 07/03/2006 9:33:58 PM PDT by fella (Respect does not equal fear unless your a tyrant.)
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To: Central Scrutiniser

Hehe. I like the pic of Jesus riding the dinosaur.


219 posted on 07/03/2006 10:33:04 PM PDT by NoCurrentFreeperByThatName
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To: Skooz

Wow, you find a hatred of Christians in the sentence that states that the Christians that confuse conservatism with their religion should go hang with the dims. You are either blind or intentionally thick as I have stated, restated, clarified, and reclarified that statement over and over and you are still harping on it.

I think I was right the first time about you. Everyone else understands the statement except you and wicket and so there are only three conclusions I can draw from that.

1. Your both honestly ignorant of how the english language works.

2. You really see no difference between Christianity and conservatism/Republicans (which makes you by your own words ignorant)

3. Your just weird little internet trolls who have nothing better to do in your life than distort statements I have clarified time and again.

I am leaning towards the last one.


220 posted on 07/04/2006 7:21:15 AM PDT by Sentis (You said the world doesn't need salvation so why do I hear it calling out for a Savior.)
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