Just A Little Something To Piss Off Creationist Morons

[lilphil1989]

Even if you could argue that complete workable systems could randomly occur, they do the function for which they were designed. The nerve network is complete. The connections to the brain are there.

No-one has ever claimed that there was once a nerveless organism that gave birth to an organism with a fully functional nervous system such as we see in modern mammals. You're right that such a claim would be silly, but that is not what is claimed by the theory of natural selection.

Also, this myth that it takes millions of years for adaptations to occur could never make easier the idea that an animal would have to wait a long time for newly forming parts to become totally useful.

Are a few light-sensing molecules selectively advantageous? Yes.
Are a lot of light-sensing molecules more advantageous? Yes.
Is the ability to form a basic image in the brain more advantageous? Yes.
Is a modern day eye even more so? Yes

At every step in the evolutionary process the precursors to modern-day organs must have given their possessors an advantage over their peers, otherwise they wouldn't have been selected for.

And the idea of "forming organs" is erroneous, because natural selection is not working to a blueprint. So no-one is claiming that organisms carry "parts" that might happen to be useful in a few million years.
If something doesn't give an increased chance of survival or reproduction right now, it won't be selected for.

Notice that the parts that animals have are used from the outset. Each one forms some useful function for the benefit of the animal. Do not give me rare exceptions to this rule. Most all animals have the capacity to use every part appointed to them.

No, not always. The mutations that are useful are the ones that propagate throught the population. The ones that are not useful are not selected for. And those that are harmful are selected against, and tend to die out.