Evolution

My God...they're evolving!

I was reading Micheal Crichton's Jurassic Park sequel, The Lost World when I discovered it. By bringing dinosaurs out of pre-history, setting them down on a modern tropical island, and then suggesting that they were adapting to their new environment, Crichton confronted me with the amazing idea that the word "species" did not in fact denote a static thing, but rather something that flowed through time; something that evolved.

And by suggesting that, through this process, his already terrifying dinosaurs were becoming even more dangerous and cunning, Crichton successfully imbued the concept of evolution with a thrilling poignancy that immediately captured my imagination. The very next book I signed out of the library was The Origin of Species.

At the time I was sixteen, and I had just dropped put of school having concluded that I was wasting my time there. In retrospect - since my interest in evolution played a key role in my eventual return to the educational system - this seems more than a little ironic. But at the time, my discovery actually seemed to forcefully justify my decision to drop out of school. After all, why had I been left to languish in math, art, or "business education" classes, or been forced to read A Midsummer Nights Dream (for crying out loud), while ideas this cool remained unexplored and unmentioned? Why the hell wasn't I told about evolution in school ???

Even more disturbingly, I now know that I was not a unique case because I have met many people who badly misunderstand Darwin's theory. This is a grave tragedy: evolution by natural selection represents the single most important scientific discovery human beings have ever, or will ever make. I sincerely believe that in endeavoring to understand evolution, one becomes a better person; and that in attempting to effectively communicate it to others, one also makes the world a better place to live.

In this spirit, let me pose you a question: do you think you understand biological evolution? Here are the four most common evolution-based misconceptions that I encounter, and the reasons why they are just that. I bet you ten bucks that you've fallen for at least one of them.

Evolution is just a theory

So is the "theory of plate tectonics", but we know that earthquakes are the result of bits of the Earth's crust smashing into each other at a snail's pace. The word "theory" is actually bit of a misnomer, because it has a slightly different meaning in an academic context than it might otherwise have: this is a semantic misunderstanding.  Evolution is no less than the conceptual bedrock upon which the entirety of modern biology has been constructed: it is a theory, but it is by no means "just" a theory. It happened, is happening, and so long as life exists, it will continue to happen: evolution is an inevitability.

Humans evolved from apes

Once, a young lady asked me in all seriousness if I thought I was "more evolved" than she was; a member of my family once expressed to me a belief that humans were evolving toward some higher form of life; and many, many people are under the impression that Darwin tells us that humans evolved "from" modern chimpanzees and gorillas.

These misconceptions are all based on the mistaken assumption that there is a natural tendency for evolution to make life more complex or intelligent; the implication being that life is hierarchically arranged, with humans at the top, and below us the progressively "less evolved" chimps, dogs, fish, bacteria, and so on. But in truth, I am no "more evolved" than an earthworm (let alone a fellow human being); and although it is true that humans share a common ancestor with the other apes, we have no more evolved "from" them, than they have from us. "More evolved" does not mean "more intelligent", and neither does it mean "more complex".

(A much better way to determine "how evolved" a species is, would be to determine it's average generation time, as this is really what determines how quickly a species can thus adapt itself to changes in the environment. For example, although fruit fly evolution can be induced and witnessed in a laboratory [because they mature in about a week], we humans haven't noticeably evolved in the last 100,000 years. By the only objective measure, fruit flies are actually vastly "more evolved" than us! But I digress.)

Instead, this is how you should really be thinking about evolution: imagine a stream. The water in the stream must constantly change it's "shape" in order to flow around corners, over rocks, and through shallows. But no particular shape is better or more advanced than any other, because the water must tailor itself to best suit it's immediate surroundings. And so it is with life: no one species can ever be said to be "more evolved" than another: in fact, it is an utterly nonsensical statement.

(Watch for this mistake in movies, books and TV shows. If I remember correctly, I think Crichton made this mistake in The Lost World. And the climax of this otherwise promising scene from Star Trek: Voyager gave me nightmares for weeks.)

Evolution is due to random chance

This is a favorite avenue of attack for creationists, who hold that we are forced to choose between believing that all life is just a huge freak accident, or accepting that it has somehow been deliberately designed (which, of course, implies a designer).

Unfortunately for the creationists, however, and as Richard Dawkins has often emphatically pointed out, natural selection is not random. Indeed, our first clue should come to us from the very words "natural selection", which were chosen to convey why this is so. Although genetic mutations occur "by accident", the process that favors the propagation of one over another is anything but random.

Since Darwin, few rational biologists have claimed that complex life owes it's entire existence to chance. In fact, this was one of his great insights: before Darwin, atheists were hard pressed to explain the existence of complex life without invoking random chance, which is obviously preposterous.

The survival of the fittest

First of all, you can survive all you want, and you will not necessarily evolve. Reproduction is the real goal; survival is just a means to that end. Remember, individual organisms do not truly evolve: it is only by imperfectly replicating themselves that they can do so (I say "imperfectly" bearing in mind this species of lizard that is asexual and all-female; and consequently is also at an evolutionary dead-end).

Second, the precise meaning of the word "fittest" is frustratingly elusive, which makes it inherently misleading. Not least of all it again implies that the "family tree of life" is a hierarchical structure, and that evolution is a race to the top. In part due to these drawbacks, most biologists now agree that "the survival of the fittest" is an unfortunate way to describe how evolution works. It should be more accurately stated "the reproduction of the best adapted", although this too fails to accurately sum up this deceptively simple (hmm...by which I mean "complex") concept.

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A basic understanding of evolutionary theory is necessary for our two greatest medical advances - vaccines and antibiotics - to remain effective; to agriculture, and for meaningful participation in the debate about GMOs; to free us from the tyranny of religious belief by explaining why God need not exist should we not want it to; to help us infinitely better understand ourselves and the natural world around us; and even supplies us with an interesting model around which to construct our own creations.

So, with all due respect: screw thou, Shakespeare! Move over for Darwin already! If the world's a stage, then evolution really is the greatest show on Earth.

Now! About that ten bucks...