Vision and Evolution (A Critique of Dawkins)

[John 6IX Breezy]

Diving further into usefulness, evolutionary emergence, and the order of development.

Digestive systems.  Our digestive systems are contemporary representatives of one of our lineages earliest adaptations.  Yet, they are not fully formed or functional until well after our birth.

This issue that delayed systems run into is covered for by another set of adaptations, our mammalian apparatus.  Human beings are literally born with “half a digestive system”.... but it’s still useful, and you certainly wouldn’t want to be born without one.  In a series of gradual steps that culminate months after our delivery, it becomes fully functional (most of the time)....though people’s changing environments can make it less functional with respect to what food sources we have available.  Or more, with some other adaptation, like an enzyme in our saliva, or the increased ability to process grain.  An increased capacity to host beneficial bacteria, even.

Those that survive and breed pass on the architectural plans for building yet another “half an x”.  Everything is always, potentially, half a whatever it is.  We don’t have any idea what maximal improvement or function would look like, or how we could even quantify it.  This destination of yours is not part of evolutionary theory or borne out by any fact of biology.  Even fully formed or functional organisms continue to express mutations over the remainder of their lives.

All that can be said here is that the problem you have with biology is that it has no destination.  Well, okay... but that’s your problem, not an issue for biology.  It just keeps plugging along regardless of our misgivings about how it operates.  I’m sure we could all write a tome about how we wished our biology operated in contrast with how it does, lol.

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A short, fun way to describe what evolutionary biology is doing, is to imagine barrels full of darts being thrown at a wall.  Some hit the target, some don’t.  Evolutionary history, in reference to current biology, is the story of which darts hit, and how.

Every generation, the darts that miss are discarded, the darts that hit are retained, and new darts are added to the barrel.  Rinse and repeat.

To be clear, my position is that evolution does predict a destination; so that isn't a problem I have with evolution, its a disagreement I have with you on how evolution works. Organism are not free flowing on a journey as you say, they are pushed and limited by selective pressures. Pressure which will push organisms towards a specific direction until that pressure is dissipated by adaptation at a specific state. Unless we are talking past each other, I don't see why biological organisms would be exempt from the rest of the physical universe which seems drawn towards states of balance and rest and efficiency. Think planets in orbit, sodium levels within cells, and almost everything else has a state of rest, biological organisms are no different.

As to your dart analogy, I agree. But I think it helps illustrate my position of how gradual progression runs into problems that only whole steps can fix (i.e. brain and eye evolving simultaneously, not one at a time). To replace your dart analogy with frogs (not to be taken seriously). If a frog needs to jump 5 meters to reach a ledge, jumping 4.5 meters is no better than jumping 1 meter. A frog shouldn't benefit from gradually jumping a bit further, if a bit further falls short of the 5 meter threshold. It seems to need an all-or-nothing adaptation to reach the ledge, or be very lucky.

That being said, I can see how your example of the digestive system can be delayed, or can evolve and develop gradually, without issue. So I think its important to distinguish between two kinds of evolutionary changes. There are indeed those in which any change is better than nothing, where any increment adds a benefit (for example more muscle fibers). But there are also those changes that need to reach some threshold before it can be functional, (enough muscle fibers so that the frog reaches the 5 meter mark).

Some functions need more than gradual improvements, vision is one of them.

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So we agree that there would be a disconnect between the two; that the way the eye develops would, in fact, be opposite to the way it evolved? I'm fine if there's no rule constricting the embryonic development of the eye to the temporal order of its evolutionary emergence. However, if such is the case then you (or evolutionary biologists) would need to account for the structural discrepancies between the two orders. For example, at what point in our evolution did the retina become inverted? Or at what point did the eye go from a folding of light-sensitive cells in the exterior surface of the organism, to a folding of neural matter (brain) within the organism that makes its way to the surface?

Can we just skip right to punchline here?  “Therefore magic!”

Tell us, since you are so interested in mechanisms of action, how did god design the eye? If you spent as much time and energy investigating your own theory as you do trying to debunk the current working explanation, you’d realize it’s a non-starter.

I have no punchline.