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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: null and void
What do primary colors look like? Serious question. I'm I guy, I "know" five colors. Not three...

Well, there are only three primaries because we have three color photoreceptors. The other colors are a result of mixing signals of these three photoreceptors. A fourth receptor, for UV in this case, would yield a fourth primary and a colorspace with an added dimension. You also have bto keep in mind that color is a neurologicalperception in the brain and not a real, physical property. For example, two beams of light entering the eye may have completely different spectra in the visible region yet will be percieved to have identical color.

301 posted on 07/05/2006 8:31:25 AM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: GourmetDan
We do not see legs 'evolving' today. Why should that process have stopped? No reason.

Actually, every subsequent generation born is an example of evolution. No organism born has a *perfect* duplication of the parental genes.

302 posted on 07/05/2006 8:39:36 AM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: doc30

Verrry interesting. Bookmark for later


303 posted on 07/05/2006 8:44:58 AM PDT by TX Bluebonnet
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To: doc30

BTW GourmetDan, do you have any comments or thoughts related to tetrachromic vision in most vertebrates except mammals? You know, the actual topic of this thread?


304 posted on 07/05/2006 9:15:03 AM PDT by doc30 (Democrats are to morals what and Etch-A-Sketch is to Art.)
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To: GourmetDan
Yes, Newtons words do speak for themselves and they did not require that man reject creation to pursue science.

On what post did reject creation?

305 posted on 07/05/2006 10:03:42 AM PDT by js1138 (Well I say there are some things we don't want to know! Important things!")
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To: doc30
You also have to keep in mind that color is a neurologicalperception in the brain and not a real, physical property.

Exactly. I don't 'see' only the 'primary' colors as 'primary colors' in my mental palette, only as some of the 'distinct' colors I see.

306 posted on 07/05/2006 10:06:29 AM PDT by null and void (Good advice is always certain to be ignored, but that's no reason not to give it. - Agatha Christy)
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To: doc30; GourmetDan
"Be careful, b_sharp. GourmetDan may next say the universe was created with the appearance of the age we see so you haven't falsified YEC. I can't make this stuff up."

What is truly frightening is that someone had to make it up.

I suspect GD would rather just imagine that the evil anti-god science conspiracy is fudging their 'interpretation' of the physical data. (You know, a lot like the Bariminology chaps are doing).

307 posted on 07/05/2006 10:08:18 AM PDT by b_sharp (There is always one more mess to clean up.)
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To: GourmetDan
You made the claim that gene duplication always results in a "freak," or, a reduction in fitness for successive generations.

Can you support that claim with a reasoned biochemical and ecological argument or can't you?

308 posted on 07/05/2006 10:11:27 AM PDT by staterightsfirst
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To: Radix
" How long have fungi been classified as Eukaryote organisms?

"Taxonomy is an ongoing process.

I never said that it wasn't an ongoing process. The field is so ongoing that there are many minor squabbles going on between the various schools of thought.

However that doesn't change my point. The Baraminologists are claiming that evolutionary taxonomists and paleontologists are, through the placement of organisms in specific classes, attempting to bolster 'evolution'. The vast majority of organisms were already in place before biological evolution was ever formalized and match quite closely the order Genomic studies suggest. If the majority of classification was accomplished before the formalization of Evolution how can they claim that Linnaean taxonomy was designed to bolster Evolution? Obviously they can't.

BTW, developing a classification system based solely on differences will produce completely arbitrary classes.

309 posted on 07/05/2006 10:22:54 AM PDT by b_sharp (There is always one more mess to clean up.)
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To: Dimensio
"You are not suggesting that there are those so out of touch with reality as to make such a claim, are you?"

LOL. No 'suggesting' about it.

310 posted on 07/05/2006 10:25:30 AM PDT by b_sharp (There is always one more mess to clean up.)
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To: GourmetDan
"Poor guy. Still doesn't know the difference between an observed gene duplication and an assumed one. That's the problem w/ these guys. Their imagination is transferred into reality in their minds and they think that everyone else has to accept it."

I take it you wouldn't be interested in the rational behind believing this instance of gene duplication? You would rather just hand wave it and all other inferential methodology away so it doesn't bother you.

This means of course that we should not believe that large meteors occasionally hit the earth, that super volcanoes have in the past caused massive destruction, that geologic strata have a chronological order, that layers of rock crack and are refilled, that intrusions, uplift, and fold occur, and that paternity can be determined through DNA comparisons. Hell, we might as well dump all of quantum physics.

DNA can be read like a book. We don't understand all of it yet but have learned much in the last 50 years. Part of what we have learned is how to recognize events that have modified the genome in unexpected ways. The reason I mentioned the number of geological features and processes in the paragraph above is because there are parallels in the way the physical data are analyzed in the two systems.

I suggest you investigate the methods used to determine events within the genome before you brush it aside.

311 posted on 07/05/2006 11:07:23 AM PDT by b_sharp (There is always one more mess to clean up.)
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To: GourmetDan
"Ah yes, redefinition. That always helps to deceive.

"Evidence is facts. Interpretation is speculation.

"To equivocate speculation w/ 'evidence' is to deceive.

"The basis of evolution.

I wasn't redefining anything, I was clarifying my definition to avoid any misunderstandings. If I intended to deceive I wouldn't have bothered to explain my terminology.

I do not appreciate you calling me a liar and I do not appreciate your attempts to introduce a red herring into the discussion.

If you want to discuss dishonesty in regards to 'fudging the books' then let's discuss the honesty (or lack thereof) behind Baraminology. Or if you prefer we can discuss the honesty behind the many creationist quote mines found on the Web. Or perhaps the honesty Kent Hovind displays.

There are plenty of creationist honesty issues we can discuss, evidence of it is all over the Web, you just have to pick one.

312 posted on 07/05/2006 11:20:17 AM PDT by b_sharp (There is always one more mess to clean up.)
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To: stands2reason

Point taken. That said, I think that the noise level of discourse may need to be taken down a notch or two.

There are wacky folks with pretty much every point of view represented in Free Republic - mine, yours and whatever.

Blessings


313 posted on 07/05/2006 11:49:37 AM PDT by Wicket (God bless and protect our troops and God bless America)
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To: GourmetDan
"We do not see legs 'evolving' today. Why should that process have stopped? No reason.

We have intermediates of fin to leg development and leg to fin development in extant organisms. There are multiple species of fish that show not only the ongoing development of legs but the development of lungs from swim bladders. We have a number of mammals that are in the process of losing their legs and gaining fins. We have a substantial line of fossils that show the change from land mammals (artiodactyls) to whales. We occasionally find whales with small useless hind legs and more developed hips than normal. The data is out there and gives a well defined path to the conclusion that whales descended from terrestrial mammals. DNA analysis of a number of extant land mammals (Artiodactyla) and whales verifies their relationship.

"You do not understand that imposing a 'leg evolution' sequence on a jumbled mess of geology is not science."

The dates of the rocks and the diagnostic morphology of the organisms aside from the legs, as well as the fossilized ecology, impose the sequence. The vast majority of fossils that show the development of legs from fins also show other diagnostic traits that place them in the sequence. Do you honestly believe that the fin to leg sequence is the only fossil evidence for the transition?

314 posted on 07/05/2006 11:49:40 AM PDT by b_sharp (There is always one more mess to clean up.)
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To: b_sharp
Or perhaps the honesty Kent Hovind displays.

BWAAAAAAAAAAAAAAAAAAAAAAAAAHAHAHAHA!

That would be a short discussion.

315 posted on 07/05/2006 1:30:47 PM PDT by balrog666 (There is no freedom like knowledge, no slavery like ignorance. - Ali ibn Ali-Talib)
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To: staterightsfirst
"You made the claim that gene duplication always results in a "freak," or, a reduction in fitness for successive generations."

I guess 'freak' is some new technical term along the lines of 'loss of function is only decline'. I guess subjectivity is the new creationist methodology when determining fitness.

316 posted on 07/05/2006 2:04:37 PM PDT by b_sharp (New Creationist Mantra - Objectivity? Objectivity? We don't need no stinkin' objectivity.)
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To: Sentis; Skooz
[should creationists be D*m*cr*ts]

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.

They are pushing affirmative action to force their claims to be treated as though they were science in public school classes. Really no different than Ebonics or Afrocentric history.

Something that is often forgotten on these threads is that many, maybe even a majority, of creationists are already D*m*cr*ts - black churchgoers.

317 posted on 07/06/2006 12:37:42 AM PDT by Virginia-American
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To: stands2reason; Central Scrutiniser
...but because they are not strict Bible-believers, they are not conservatives.

Not a very good attitude if you're trying to expand a political movement.

318 posted on 07/06/2006 12:52:06 AM PDT by Virginia-American
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To: GourmetDan
...Dogs, coyotes and wolves are separate species but the same 'kind'. They can all interbreed...

Chihuahuas and great Danes? Mating, not being fertilized in a Petri dish? I'm climing that the sizes are too different. Show me some proof if they're not.

319 posted on 07/06/2006 1:05:01 AM PDT by Virginia-American
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To: b_sharp
...The platypus (Ornithorhynchus anatinus) commonly known as the duckbilled platypus is an animal that has webbed feet, flat tail (much like a featherless bird's), a duck's bill and lays eggs for reproduction. Because the evolutionary method (EM) uses similarities to place organisms this animal is generally placed taxonomically with mammals, simply because its feathers resemble fur. ...

wow

320 posted on 07/06/2006 1:22:50 AM PDT by Virginia-American
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