Percy:
Hi, sorry, I don't have much time lately for discussions, so my answer is late, of course...so quickly:
Percy writes:
Bird and bat wings are just adaptations from front forelimbs.
Both of us now why you haven't mentioned insect wings, for example.
Their wings have all the same major bones and basic structure as forelimbs. To suggest an example, gradual changes could add some gliding capability, like the flying squirrel with the extra skin between it's forelegs and body.
Did it just appear? Or were there some stages when extra skin was developing. Of course there couldn't be any otherwise it would be fatal disadvantage.
And both of us know why you haven't mentioned how bird wings work, why you haven't mention its feathering.
If gliding provides a survival advantage, then flying squirrels with allele combinations or mutations that make gliding easier or more effective will survive to spread their genes throughout the population.
So... if extra skin and so these kind of "wings" were not "developed" at once, "partly-mutated" animal would naturally die... that's clear.
If we're talking about a creature with a brain, then the skin is already connected to the brain by nerve cells. Any mutation causing some skin cells to be more light sensitive would send signals to the brain when light strikes them. The light would probably be interpreted by the brain as heat or touch contact, depending upon which nerve cells connected to the skin respond, but natural selection would favor those individuals whose brain made the most of the information, and the interpretation of the light signals would improve in the population over time.
This is an evident fantasy I won't comment as you've completely forgotten (ignored?) about a mechanism in brain needed to "decode" signals created by vision I was talking about.
Loudmouth:
Those two small brown dots on the upper left are eyespots. They are not eyeballs, but patches of photosensitive cells arranged inside of a depression, much like a human retina without the rest of the eye. Planarians are able to sense light and the direction the light is coming from which allows them to respond to light stimulus.
These are very very simple "eyes"... yes, there is retina, no lens, no cornea. (these "eyes" are also mentioned in a website I have already mentioned before)
They do all of this WITHOUT A BRAIN. Therefore, your statement is absolutely false.
No. They do all of this WITH A BRAIN. Therefore,
your statement is absolutely false.
If you like I can find for you "hundreds" of websites to show you a proof but I don't think you will ask me to do it.
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