Evolution of the Eye

[Galapagos]

Originally Posted by doggone

I’m not saying someone, someday, won’t come up with a working theory for how the eye could have evolved into being. I’m just saying that it doesn’t exist now. Not even close.

This explanation is perfectly adequate, and it is experimentally demonstrated using a camera representing photosensitive cells that the intermediate steps would certainly be beneficial to an organism:

YouTube - Richard Dawkins on the evolution of the...

YouTube - Richard Dawkins on the evolution of the...

The History Channel also has a new show about evolution entitled "Evolve"(which premiered last night) and the first episode was about eyes. You would certainly benefit from and enjoy it if you are curious:

Evolve - Eyes

And here is a video featuring some members of the NCSE discussing evolution of the eye:

YouTube - Creationism Disproved?

[Galapagos]

Digging up an old thread here, but I wanted to make this info available to anyone who stumbles on this thread via search engines:


****EDIT-- my apologies. these were available for free about a week or so ago, but....
-EDIT 2-- okay, they're free again... maybe it was just my computer.. enjoy!


Via Genomicron: The journal Evolution: Education and Outreach recently had a special issue on eyes, with several very accessible papers. These should prove both informative and useful to students, instructors, parents, curious laypeople alike. Highlights here:

Introduction by T Ryan Gregory

Casting an Eye on Complexity by Niles Eldredge

The Evolution of Complex Organs by T Ryan Gregory

Opening the “Black Box”: The Genetic and Biochemical Basis of Eye Evolution
by Todd H. Oakley and M. Sabrina Pankey

A Genetic Perspective on Eye Evolution: Gene Sharing, Convergence and Parallelism
by Joram Piatigorsky

The Evolution of Extraordinary Eyes: The Cases of Flatfishes and Stalk-eyed Flies
by Carl Zimmer

[stereologist]

It's quite odd for doggone to suppose that something must be working for it to be working. Things are not reasonable in evolution.

The reason we see light is that light does not destroy molecules quickly. I can already hear the blather on that last line, but really folks light is just strong enough to cause chemical reactions while most molecules are stable. That's just enough to sense without destructive sensing.

There are lots of chemical reactions involving light. Curtains fade. Some things bleach. Some things yellow. Other things age and become brittle.

So an organism might end up with photosensitive materials in it. Some die. Some live. The ones that live pass on their genetic heritage. An organism that reacts to changes in light might live or die. An organism that does not react to light changes might live or die.

Suppose the animal reacts when light goes to dark. Should it run from an attacker or be the attacker and eat the prey? Does this have to be be purposeful or can this be accidental? All that matters is that if the genes are passed on, then the species survives.

[Michaelangelica]

Plants too, sense light.
Many are heliotropic,to the extent that you can watch their movement during the day.
eg Heliotrope