As Eric Cartman so eloquently stated, "Creationists piss me off." (Ok, ok, so he didn't say it; I did.) Creationists always trot out ridiculous arguments for their faith-based delusions, such as how the human eye is somehow "proof" of "intelligent design". To which I always say, if humans are the work of an intelligent being, that being must be an engineer, for only an engineer would run sewer lines through a recreational area.

Before I get to today's story, some background. About twenty years ago I read Richard Dawkin's book The Selfish Gene. In it he set forth the proposition with how humans are nothing more than meat machines created to reproduce the information viruses we call "genes". Over millions of years genes have tinkered with us to create ever more impressive structures to react to the environment and reproduce them, since they cannot act in real-time. The Selfish Gene remains one of the most amazing books I have ever read, and it truly altered the way I think about people and the world.

Like successful Chicago gangsters, our genes have survived, in some cases for millions of years, in a highly competitive world. This entitles us to expect certain qualities in our genes. I shall argue that a predominant quality to be expected in a successful gene is ruthless selfishness. This gene selfishness will usually give rise to selfishness in individual behavior. However, as we shall see, there are special circumstances in which a gene can achieve its own selfish goals best by fostering a limited form of altruism at the level of individual animals. 'Special' and 'limited' are important words in the last sentence. Much as we might wish to believe otherwise, universal love and the welfare of the species as a whole are concepts that simply do not make evolutionary sense.

The Selfish Gene

About a decade ago Richard Dawkin's wrote a cogent, sensible, systematic, and somewhat definitive deconstruction of the creationists' arguments about how the the eye proves intelligent design. When I again stumbled across it today I thought it worthy of sharing.

Thus the creationist's favourite question "What is the use of half an eye?" Actually, this is a lightweight question, a doddle to answer. Half an eye is just 1 per cent better than 49 per cent of an eye, which is already better than 48 per cent, and the difference is significant.

When one says "the" eye, by the way, one implicitly means the vertebrate eye, but serviceable image-forming eyes have evolved between 40 and 60 times, independently from scratch, in many different invertebrate groups. Among these 40-plus independent evolutions, at least nine distinct design principles have been discovered, including pinhole eyes, two kinds of camera-lens eyes, curved-reflector ("satellite dish") eyes, and several kinds of compound eyes. Nilsson and Pelger have concentrated on camera eyes with lenses, such as are well developed in vertebrates and octopuses.

Where d'you get those peepers

These writeups on the eye from Paul Patton at the University of Illinois and Kenneth Miller at Brown may help explain things more. In addition, there is an interesting exploration of the aesthetic arguments raised by Dawkins with respect to the retina's design.