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Unpopular Ideas

Ramblings and Digressions from out of left field, and beyond....

Location: Piedmont of Virginia, United States

All human history, and just about everything else as well, consists of a never-ending struggle against ignorance.

Sunday, November 19, 2006

Our Slapdash Eyes

In the scientific political world a fight is going on that has no foreseeable end: the one between the evolutionists and the creationists. In recent years the latter sensed the growing weakness of their position, and their response was to revamp their theology a bit along with giving their cause a new name, Intelligent Design. But their main theme remains unchanged. God, not Evolution, is reponsible for the origins of the various species.

A great place for keeping track of the latest salvoes in this struggle is The Panda's Thumb site. And recently they cited an article that they had seen in another interesting science site, Pharyngula.

That article started with the following paragraph:

Ian Musgrave has just posted an excellent article on the poor design of the vertebrate eye compared to the cephalopod eye; it's very thorough, and explains how the clumsy organization of the eye clearly indicates that it is the product of an evolutionary process rather than of any kind of intelligent design. A while back, Russ Fernald of Stanford University published a fine review of eye evolution that summarizes another part of the evolution argument: it's not just that the eye has awkward 'design' features that are best explained by contingent and developmental processes, but that the diversity of eyes found in the animal kingdom share deep elements that link them together as the product of common descent. If all we had to go on was suboptimal design, one could argue for an Incompetent Designer who slapped together various eyes in different ways as an exercise in whimsy (strangely enough, though, this is not the kind of designer IDists want to propose)…but the diversity we do see reveals a notable historical pattern of constraint.

Say what? Poor design? Clumsy? Awkward? Exercise in whimsy? Are they talking about our eyes, those amazing organs that enable us to see all the myriad colors of the autumn forest, and to distinguish all the subtleties of human face, and to detect objects millions of miles away as well as right on the tips of our noses? Those orbs that are the most beautiful features of the human body and that are seen as windows into souls and minds? Those terrific instruments of vision that, barring mishaps, can keep operating to some degree for a century or more? Delicate globes that nevertheless can survive all but the most crushing of blows? That's poor design?

And here I had been going around praising in my mind every day the miracle of the human eye and the abilities it gives us to sense our immediate and distant surroundings with such acuity and thoroughness.

I've been doing this lately because a few years ago I was diagnosed with glaucoma, a condition that I am stuck with from here on out as there is no cure for it. I've had the laser thing done on my left eye and I have to take drops every day to keep the pressure on my optic nerves under control.

This started when, for a short time, I had floaters in my right eye, the weaker of the two. As I do with any physical difficulty that pops up, I just wished it away, but a year or two later I decided that I didn't like what was happening with my vision, especially in my right eye, and I went to see the optics doctor. Oddly, however, the pressure was worse in what I thought was my good left eye, hence the laser. The trouble with the right, which remains unlasered, is not so much the optic nerve as it is a small cataract.

As of now I can still see most stuff well enough, except very small print, and my only complaint is a very vague mistiness, as if I'm viewing the world through the thinnest of stage scrims -- though like so much else in my life, I don't know if that isn't purely mental, a product of my fears. Meanwhile I am extremely grateful that my eyes aren't any worse, because everything I do is so dependent on vision.

I wonder what these scientists would call an optimal design? Would it be for our eyes to have the abilities of an electron microscope combined with those of the Hubble telescope, along with 360-degree peripheral vision? For myself I'm more than happy with them the way they are. I think they're a great bargain that we've struck at conception with whatever is responsible for endowing us with them.

The Pharyngula article, however, is well worth reading, though you could eventually get lost, as I did, in the wealth of detail about the eyes of our fellow creatures as well as our own.


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