Intelligent Design: Irreducible Complexity?

[John V]

And if I don't know, does that somehow make the reason wrong? Why would you go with such an obvious argument from ignorance?

I asked for step by step development. Why would you jump in and claim to know all the steps if you don't?

Besides, you understand that there are other methods of detecting the day/night cycle than light detection, right? Bloody fetuses have a circadian rhythm, you know. Ain't no light where they are. Circadian rhythms in particular are very easily obtained, even cyanobacteria can have them.

Then circadian rhythms aren't a reason that a light sensitive cell is advantageous.

Because larger patches of light sensitive cells allow an organism to better detect things moving in front of light sources, like obstacles or predators. Danger. Hence, it's a survival enhancer. How did it initially develop? Mutation, like everything else.

How does the organism know what to do with that information? Again, I could have a light sensitive cell on my elbow, but it's not doing me any good.

Again, it began as a mutation, but being able to monitor direction with greater specificity is an even better survival mechanism because now you have a better idea of where the danger is coming from.

How does the organism know that a signal from one cell indicates one direction, while a signal from another indicates another direction? How is the organism being signaled from those cells? How does the organism know that a signal from those cells indicates danger?

That's already been explained to you: light sensitivity without a method of processing the input isn't a disadvantage, and so it persists in those that develop it. From there, all it takes is one mutation to give even a little processing ability to be a pretty nice survival advantage. See, mutations don't just vanish after one generation if there's no use or advantage to them.

According to the TO link I provided, "most neutral alleles are lost soon after they appear."

My contention is that "somehow" isn't an adequate explanation.

Mutations happen randomly. Don't blame me, blame imperfect gene transcription. Oh, and "this isn't an adequate explanation of the evidence that shows that it did happen," is an argument from ignorance. [/quote]
I asked for a step by step explanation. If you can't provide that, you shouldn't have butted in.

"It's improbable, therefore it's impossible," really?

Impossible? No, but every time you need to posit neutral mutations hanging around, you're unwittingly supporting irreducible complexity. You don't seem to know what the irreducible complexity argument is.
http://en.wikipedia.org/wiki/Irreducible_complexity

Irreducible complexity (IC) is an argument by proponents of intelligent design that certain biological systems are too complex to have evolved from simpler, or "less complete" predecessors, through natural selection acting upon a series of advantageous naturally occurring, chance mutations.

So, when I ask for a step by step explanation in a thread on irreducible complexity, it's implied that each step is advantageous on its own.

It's trivial to say that anything that exists could possibly have evolved if you allow neutral mutations to build up until they're advantageous.