Creationist and extinct species

[InfiniteNow]

On the other hand, a good argument made by creationists is that we have never observed macroevolution-the evolution of a completely new complex body organ. how would this occur by chance and natural selection? Take the eyeball, for example. there are hundreds of thousands of chemical reactions that happen every moment in the eye which result in sight. Take a single reaction out of the equation, and then you are blind. How did the eye evolve gradually, by chance?

Start here, come back later... when done:

 

http://hypography.com/forums/biology/11406-evolution.html#post172498

[Southtown]

I personally believe in guided evolution.

 

On the one hand, Evolution HAD to have happened, unless an intelligent creator decided to create the illusion of age inherent in the cosmos-just to deceive us.

 

...But that's a completely absurd idea.

I'm a Young-Earth-Evolutionist. Just look at the abortion issue. In fifty years, who will have the most offspring, the pro-choicers or the pro-lifers?

 

On the other hand, a good argument made by creationists is that we have never observed macroevolution-the evolution of a completely new complex body organ. how would this occur by chance and natural selection? Take the eyeball, for example. there are hundreds of thousands of chemical reactions that happen every moment in the eye which result in sight. Take a single reaction out of the equation, and then you are blind. How did the eye evolve gradually, by chance?

They say it served another purpose in the meantime, before it gained it's present capabilities.

[Glotesqyphon]

I'm a Young-Earth-Evolutionist. Just look at the abortion issue. In fifty years, who will have the most offspring, the pro-choicers or the pro-lifers? :hyper:

 

 

They say it served another purpose in the meantime, before it gained it's present capabilities.

 

What purpose would blind eyeballs serve for survival over the course of millions of years?

[ughaibu]

There's no reason to imagine them starting out as eyeballs. Think about euglena, snails, spiders, etc.

[Glotesqyphon]

There's no reason to imagine them starting out as eyeballs. Think about euglena, snails, spiders, etc.

 

 

Do euglena see?

[ughaibu]

I very much doubt that they see beyond a sensitivity to light.

[InfiniteNow]

What purpose would blind eyeballs serve for survival over the course of millions of years?:D

 

I think the basic issue is the manner in which you are approaching this question.

 

Since the beginning of time, there were certain characteristics which proved useful in the environment where they were found... even down to single celled organisms. Basically, those traits which allowed the organism to find food and/or reproduce more successfully than organisms who did not have those traits would be selected for, as the more successful adaptation will tend to do better than less successful adaptations.

 

At some point, and I'd postulate it has to do with photosynthesis, the ability to detect light in a very rudimentary fashion became a useful trait, and spread through the years. As it continued to spread, it also changed and mutated. Some of these mutations were for the better, some of these mutations were for the worse. Clearly, those that were "for the better" reproduced more successfully and their offspring shared the trait and passed it on to their offspring.

 

Eventually, the eyeball became more common, and new abilities slowly became selected in that. Seeing motion better in the dark is clearly a good adaptation if the rest of your group are being eaten by a nocturnal hunter. :(

 

So, it really just means that enough generations (we're talking millions here) have lived and died and those that could "see" the best were selected for in our particular branch of the tree of life.

 

Even within today's humans, some can see better than others. It's genetic.

 

Try to remember, when considering all of this, that not all life forms have evolved an amazing sense of vision. Others, like the mole or sewer rat, really have little need, so the traits that were selected in (which benefited) them would be sense of smell or sound... which are more useful in dark habitats.

 

 

What most people struggle to do successfully is wrap their heads around just how long this all took. It's disconcerting for some to think how old the planet is, and how small a fraction of time we've been a part of it. If the age of the Earth was represented by distance, it could be the entire journey from New York to San Francisco. Humans, or bipedal primates, only came onto the scene (using this distance analogy) at a distace of your neighbors house. The changes are subtle, but there over great distances of time.

 

 

;)

[Glotesqyphon]

I'm no expert in evolution.

 

But my question is, how did the very first eye evolve? I'm not certain what the first eye was like. But it couldn't have been THAT simple. Mutation... blind organisms were exposed to light. Does that mean their cells are just going to start finding a way sense the presence of light? That seems plausible. But on any level of sight-evolution, one slight mutation that digressed from the chemical processes if vision would result in BLINDNESS. Those individual creatures would not be good candidates for passing on their genes. And considering the vast timescale we are looking at, a blind or even visually impaired genetic line is not going to take over the lineage of the species.

[ughaibu]

The first eyes would probably be on the lines of euglena's eye-spot. Try reading InfiniteNow's post again, then try thinking about euglena, snails, spiders, etc.

[Glotesqyphon]

The first eyes would probably be on the lines of euglena's eye-spot. Try reading InfiniteNow's post again, then try thinking about euglena, snails, spiders, etc.

 

I'll grant that simple eyes like those could have evolved naturally. But what happens when those eyes begin to mutate? Not better vision.

 

If I'm wrong, please tell me how.

[ughaibu]

What do you mean? Of the mutations that occur the advantageous ones will be selected by environmental pressure, ie evolution.

[Glotesqyphon]

What do you mean? Of the mutations that occur the advantageous ones will be selected by environmental pressure, ie evolution.

 

 

I see what you mean. It's just hard for me to imagine how long it would take for a mutation to be exactly the one needed to equal better vision. Yes, we're talking millions of years, but it seems like it would take hundreds of billions of years for something as simple as a microbial eye-dot to adapt into something as complex as a mammalian eye.

[InfiniteNow]

I see what you mean. It's just hard for me to imagine how long it would take for a mutation to be exactly the one needed to equal better vision. Yes, we're talking millions of years, but it seems like it would take hundreds of billions of years for something as simple as a microbial eye-dot to adapt into something as complex as a mammalian eye.

 

I don't know mate, the mammalian eye is not even really that good. You might try listening to this story for a theory on it, and read the surrounding article which essentially mirrors what I typed above:

 

 

Five minute RealPlayer Clip - Click here

Five minute Quicktime Clip - Click here

 

 

Evolution: Library: Evolution of the Eye

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.

[Glotesqyphon]

You have answered my question well. That makes perfect sense. But to me "GOD" is simply Existence, and "Random" is the only impossibility. Everything happens from a cause. So in my mind evolution is still "guided" from the space beyond past, future and causality. :)

[InfiniteNow]

You have answered my question well. That makes perfect sense. But to me "GOD" is simply Existence, and "Random" is the only impossibility. Everything happens from a cause. So in my mind evolution is still "guided" from the space beyond past, future and causality. :eek:

 

Glad it helped. Sometimes topics are difficult to understand. I struggle everyday with various ideas and concepts. While I don't approach my own life this way, it's fine that you have the belief you do. Perhaps you could make your belief more robust by working harder to understand the real underlying nature of things. If you believe in God, then you'll get to know him better by learning some science. :)

 

 

Cheers. :hihi:

[Buffy]

But to me "GOD" is simply Existence, and "Random" is the only impossibility. Everything happens from a cause. So in my mind evolution is still "guided" from the space beyond past, future and causality. :esmoking:

Randomness is easy! Roll the dice!

 

It is unfortunate though that some people--for nefarious purposes in my mind--like to promulgate the notion that each act of randomness requires that all previous acts of randomness be repeated over again in order to "progress" which is convenient if you are trying to promote all constructive events as being driven by an outside intelligence. This is one of the many fallacies--piliing up coincidences to make the end result seem "impossible"--aimed at tearing down Evolution that simply do not hold water.

 

In other words, if you persist in believing that in order to get an eye, that there must be an a priori purpose and goal: notions that are *only* applicable if you are seeking a "creator." No evolutionary trait need be used in the beginning for its later purpose. Just as with they eye that started out simply as a mechanism for sensing "light vs. dark" and evolved through steps that may have had nothing to do with vision, our own eye's ability to sense only a narrow band of the electromagnetic spectrum may be an "unexplainable oddity" to our decendents who may be able to "see" infrared or ultraviolet light or even sounds!

 

Your *attitude* about what you see can be the biggest cause for your blindness!

 

While it may be a "simpler" explanation to simply have a deity running ahead of us making everything appear the way it does, when you think about it, that's an awful lot for a deity to do, and "I don't see how she can do it all!" Wouldn't it be much simpler if it all kind of happened without anyone being responsible for making every little thing happen in a certain way?

 

Simplicity is in the eye of the beholder,

Buffy

[Glotesqyphon]

Randomness is easy! Roll the dice!

...

Simplicity is in the eye of the beholder,

Buffy

 

Uuuhhm, the die lands on a certain number because your subconscious decided to roll it a certain way. I suppose you don't get many Tarot readers in here, do you? :lol: It's really fun.

 

OK I'm just pushing buttons now, I'll shut up. :doh: