1) A simple light-sensitive spot on the skin of some ancestral creature gave it some tiny survival advantage, perhaps allowing it to evade a predator.
2) Random changes then created a depression in the light-sensitive patch, a deepening pit that made "vision" a little sharper.
3) 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.
4) Eventually, the light-sensitive spot evolved into a retina, the layer of cells and pigment at the back of the human eye.
5) 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.
From Evolution of the Eye.
Saturday, June 10, 2006
Evolution of the Human Eye
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27 comments:
I had this arguement with a door knocker once. Actually it lasted about 3 months. He just kept coming back with more "proof". He kept bringing me cartoon style books with 40pt font and stories that went "and then god.... and then god.... and then god.... and then god...."
I told him that I was obviously more evolved than him because MY eye's could see that the font is WAY too big and I couldn't respect him any more because he was some kind of lesser human..... I repressed my desire to punch him in the nuts.
Was he that tall?
lol - yeah, I used to think it was fun talking to the Jehovas. Then it got repetative....
It starts with them waving the bible at you and saying something like "Are you lonely? Do you hang around in this house all day and wish you had friends? Are you stupid enough to believe this shit? If yes, we have some Good News for you."
...and there goes another gap that people try to fit God into. It's amazing people still try to look at (ever-decreasing) the gaps in human knowledge to find God. Though I believe in God, I have little time for ID. Better to look for God through our understanding of the world rather than outside of it.
honestly, this article seems no different that your other satirical articles.
it ignores, without nerve endings already running out to the "light sensitive" spot, there is not purpose here for the spot. and why was an opening advantageous without a lens? and at what point did a tear duct become advantageous to start developing?
frankly simon, i'm quite disappointed if this is all you've got. just how do they estimate how many millions of years it would take to evolve this way when we see nothing of this sort happening now?
danny, as simon mentioned in the post, we do see this sort of thing happening now.
In fact just a couple of months ago there was something in the popular press (i think it was either the BBC or the New York Times, so most 'right thinking' beleivers wouldn't have seen it) about a recent paper on a currently living species with what can best be described a a 'transitional' eye.
I'm too lazy at the moment (it's almost midnight here in oz), but if someone wants to do the reseacrh, the truth is out there...
Amazing!!
N1?
Hey
I discovered your blog yesterday. I have read most of it but you have written a lot. This would be fine had I discovered your blog in winter, but the weather is pretty damn good at the moment and I really wanted to be outside, working on my tan.
One thing that strikes me about many of the comments on your blog (from perhaps months ago - I can't remember) is that people fundamentally misunderstand evolution. As an inevitable consequence, this makes it much easier to discredit the theory and to wrongly attribute moral shades to the theory in ways that undermine its appeal.
"Survival of the fittest" is a phrase surely utterred by many an ambitious not-quite-as-intelligent-as-he-thinks-he name-dropping dimwit who believes that evolutionary theory trumps any necessity for moral consideration.
Evolutionary theory is not ethically prescriptive.
It's like playing football applying the rules of rugby.
I suppose a lot of the confusion is caused by the arguments, particulary as I understand it in the US, that there is an incompatibility with evolutionary theory and religion. In fact, there is no necessary conflict, unless of course you choose to interpret divine texts literally in which case you're in a whole lot of trouble. Any lawyer or artist can tell you that interpretation can lead to conclusions so detatched from the intentions of the author that they can cease to have any necessary link to what was written in the first place.
Furthermore, another problem is that people understand morality and religion to be necessarily linked - that without God there can be no right and wrong. Time for a name-dropping appeal to authority.
"The idea that moral laws derive their authority from God's authorship of them was dismissed convincingly by Plato more than two millennia ago. His question, updated for our monotheistic times, is: does God command what is good because it is good; or is what God commands good because he commands it? If he commands what is good because it is good, then things are already good or bad irrespective of what he desires and we don't need God to establish morality after all. But if what God commands is good only because God commands it, that would mean that anything could be good or bad, and we're just lucky that God doesn't command us to kill and torture. Ironically, start with the idea that you need God for ethics and you end up either proving you don't, or with the ultimate form of relativism: the idea that God could make it so that "anything goes"- Julian Baggini
A lot of people wrongly use an 'appeal to authority' in matters beyond the expertise of the supposed authority. I figure that both Plato and Baggini are pretty savvy when it comes to ethics.
Which brings me to my last point (by the way I am just rambling and not in any way comprehensively ranting), that... damn it, I've forgotten.
I am sure it'll come back to me. I hate it when you lose a thought.
Time for bed. Cheers for an interesting blog.
CM
Hi, CM. Welcome. Smart comments and that quote is a good one... or nice one (thomp).
I think "survival of the fittest" works, as long as you're not so dim that you insist "fittest" can only refer to an individual and can't also include a group (business, tribe, football team, nation, culture, language, etc).
Danny, if you still don't understand it, I could explain it further. I'm not sure it's worth my effort though, as you seem to be acting like the disruptive child in class.
What happened to the humble modesty you started out with? I knew it was fake.
It is amazing, isn't it, Dabich.
See, these Brit Christians like Jonathan are far too sensible. It's much more fun arguing with people who think Genesis is literal fact.
Jonathan makes a good point, though, Dabich, don't you think?
Simon ~ Jonathon is indeed interesting. He sounds like you, without the God thing ;)
Danny, I don't fully understand survival of the fittest, either.
CM ~ Please espand on your thoughts, I'm enjoying them :)
simon,
i'm sorry that the moments that i cease to be humble cause you to further question the validity of what i am saying.
again, all i can encourage you is that christianity is not about comparing yourself to others or looking at what others believe, it is about searching the Word of God and seeing what it says.
you hit the nail on the head though. i can get proud and condescending at times.
i'll work harder at trying to apply the grace God shows me.
WHOA!!! danny, would do me the distinct honor of posting that message elsewhere?
Danny, why don't you start by showing some humility to the geologists, biologists, physisists and others who have dedicated their lives to showing us how the diversity of life was created on this planet?
At the moment, you seem to think you know more about natural selection and evolution than the scientists who have spent their lives studying it.
Isn't that arrogance in the extreme?
LOL Scribe, like in EFB's reading material???
I am God. I created you as an example for others to understand that humans are free to believe or not.
Prove me wrong.
To what purpose?
That same never ending question
lol
Cameras don't just 'evolve'. They are designed by intelligent people. Yet you are claiming that the human eye just emerged out of some primordial ooze.
That's really ridiculous. Maybe my old car will evolve into a BMW if I wait long enough.
LOL!
Brilliant, Myquestioningmind, you must have been watching these two. They're hillarious, aren't they?
As usual, as prophesied in Ecclesiastes 1:9, there is "nothing new under the sun" or on Simon's blog.
Simon, I am a geologist and a Christian, where do I fit in your jaded view of the world? Your desire to think of all Christians as victims of the "Great Brain Robbery" is an understandable but very simplistic and flawed hypothesis. Please try harder.
For those of you who "don't get" where I'm coming from, please visit http://www.geosus.org.uk
for guidance.
Martin
Someone who has been set up to look for a god, Martin, will find him anywhere and everywhere.
OK, so I took the easy route and threw a Bible verse at you. Sorry. But please don't presume to think you know how or why I chose to become a Christian.
You may be right to guess that I was brought up to believe going to Church on a Sunday was the right thing to do. You might even have worked out that I only really considered the historical reality, relevance, and significance of Jesus when, at University, I no longer had any reason to go to Church; e.g. choir, candle -or cross- carrying, youth club, bell-ringing (yes, I tried them all). However, what you don't realise (or conveniently forget) is that, at heart, I am - and have been all my life I guess - a sceptic.
Almost immediately, I was confronted by the sad fact that the majority of evangelical Christians have a very unscientific view of the Bible, just as most scientists have a very godless view of science.
However, that does not make either group right and, I for one, do not decide what I shall believe (or remain open to discovering to be true), on the basis of who shouts the loudest. The Nazis really hit the nail on the head when they said that no matter how big the lie; if you repeat it often enough and loud enough, people will believe it.
P.S. Where did you get that photo (at the top) from, by the way?
Religion is certainly the group shouting loudest, at the moment, considering atheists are out-numbered by about 6-1 in the world.
Why should science worry about gods, Martin? If scientists started trying to squeeze gods into things, we'd be going back about 1000 years.
In the long and winding road of scientific progress, not one step has been taken by religion.
From talking to various Christians, Christianity seems to be about general self-loathing and mistrust of humanity. Being brought up in a Christian society, we're given a sense of guilt about natural body functions and insticts and so we grow up feeling bad about ourselves and with a desire to "repent".
Isn't it all about feeling bad because you fancied your mate's wife, or pigged-out on a meal, or lay on the sofa watching TV all day, or wished your bullying boss would drop dead? - all things which are relatively harmless.
The picture came from a google image search. Horrible, isn't it?
"In the long and winding road of scientific progress, not one step has been taken by religion.".... If it was not for the Christian concept of a rational God, western civilisation/science would not have developed the way it has.
"From talking to various Christians, Christianity seems to be about general self-loathing... all things which are relatively harmless.".... Most of the world's belief systems acknowledge that no-one is perfect; most conceive God as perfect and/or just. Religions are imperfect man's ideas about how to make himself acceptable to such a perfect God.
Therefore Christianity is not a religion, since its central point is that we cannot make ourselves perfect and so should not make ourselves miserable trying; just be grateful that God has solved the problem.
Martin, what gives you the idea the Christian god is any more rational than the others?
Therefore Christianity is not a religion, since its central point is that we cannot make ourselves perfect and so should not make ourselves miserable trying; just be grateful that God has solved the problem.
So Christianity isn't a religion. Well, I learn something new every day.
I don't think humans not being perfect is a problem. I would hate to live with a bunch of no-it-alls who never do anything wrong - I can't think of anything worse.
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