Three and a half important facts about the theory of evolution

I was recently reading The Mind’s I, an anthology of reflections on souls, self, and consciousness compiled by two of my intellectual heroes, Professors Douglas Hofstadter and Daniel Dennett. I’m about 150 pages and all I can say is that it’s definitely a must-read. But I’ll talk about that more in some other post.

One of the pieces featured in the book was an excerpt from Richard Dawkins’ The Selfish GeneAfter reading it, I kind of kicked myself. I’d never really been interested in Dawkins before, since to me he was just that “atheist guy”; now I would revise that mental reference to read “that guy who really knows his evolutionary biology and now uses his immense prestige in the scientific community as well as his high name recognition to widely promote his views regarding religion.”

I was inspired to write this post by a reference in the excerpt to a favorite quote of mine by Jacques Monod, “Another curious aspect of evolution is that everyone thinks he understands it!” And it makes sense why. Evolution is an intuitively pleasing concept because it describes a lot of non-biological phenomena, such as the development of culture or technology. Unfortunately, primarily because of analogies drawn to precisely those examples of non-biological evolution, a lot of misconceptions are formed. So here, I try to clear up a few of those misconceptions.

I don’t claim to be an expert on evolutionary biology, since my education so far is two years of high school bio plus whatever I’ve happened to read, which, as you know already is definitely almost none of Dawkins. But what I present are a few inviolable and all-important truths about the theory which everyone should know.

1)      Evolution takes place in terms of populations and not species: This is logical but not counter-intuitive. I guess the real meat of the statement is, “Living beings cannot change themselves within their lifetimes.” This was the misconception of Darwin’s predecessor, Jean-Baptiste Lamarck, who believed things like “Giraffes have long necks from stretching up to get the leaves at the top of trees.” Wrong. It’s easy to laugh at him, but here’s a sample dialogue with an anonymous non-African (A.N.A):

A.N.A: When it’s sunny, my skin becomes darker. People in Africa have the darkest skin in the world. Many African countries are also located around the equator, where sunlight is strongest. So if I move to Africa, would I eventually become dark-skinned?
Me: Well, you would get more tanned, if that’s what you’re asking. But no, you would never become black in your lifetime. In fact, you would probably die of skin cancer, unless you wear sunscreen continuously, which pretty much stops any possible “evolution” from happening.

A.N.A: (perplexed) So how does it work then?

Me: Evolution takes place in terms of populations and not species. You would have to move to Africa with a large enough group of other fair-skinned people. Then you would also have to abandon most clothing, shelter, and definitely sunscreen. Then you would have to live in the sun for long enough that natural selection, in the form of dying from skin cancer, would begin to kill enough of you. Melanin is a substance in skin cells which not only darkens them but protects the nucleus from harmful mutations that might cause the genes to become cancerous. There would have to be sufficient variation in the amount of melanin between members of the population that some would have enough to survive some skin cancer, and then only the ones with more melanin would be able to reproduce. There would have to be enough of those to maintain a stable group over several generations so that melanin could accumulate in the skin cells and turn the population dark-skinned.

A.N.A: But…what about white South Africans? Or other whites whose families have been living in Africa for hundreds of years? What about them?

Me: Well, a couple hundred years are generally not sufficient to see any big changes. In addition, they have houses and clothes and wide-brimmed hats, and recently, sun-screen, and evolution’s not going to happen unless it’s absolutely necessary…

… And that transitions perfectly into my second point…

2)  Things do not want to evolve. Dawkins describes genes as inherently selfish, and, in a beautiful use of the philosophy of reductionism, describes evolution as selfish molecules which build elaborate “survival machines” to enhance their continued existence. They do not “want” to change, but desire to remain the same is superseded by the desire to continue existing. Basically, the idea is this: Biological systems search for equilibrium, or stability. Dawkins writes that “Darwin’s ‘survival of the fittest’ is really a special case of a more general law of survival of the stable.” The implications of this are absolutely enormous.

This idea essentially refutes two misconceptions about biology. The first is that evolution is constantly happening everywhere. This isn’t all wrong, but it seems to suggest that evolution is a purposeful process. And it absolutely is not. We only need to point to imperfections of our own body, or more startlingly, our brains, to show that evolution just creates organisms that can survive in particular settings, not perfect organisms. Evolution is driven by natural selection, which takes place because of temporary instabilities – two species occupying the same niche in an ecosystem, resources shortages, etc.
And secondly: Intelligent design is wrong! There is clearly nothing intelligent about evolution. It just occurs so that populations that possess sufficient variation to have individuals that may survive certain alterations in their environments may survive. That is why the percentage of African elephants with tusks has been dramatically reduced in the last few generations; while tusks were once an advantage to getting mates, they are now a liability because poachers kill elephants with tusks and those elephants are no longer able to pass down their tusk-genes. Only a very strange and unintelligent designer would decide to give elephants tusks somewhere along the way to elephant-enlightenment and then take them away. Talk about a lack of foresight. Sounds more like random experimentation than actual intelligence, because really, that’s what the “designer” is doing.

3)  All of biology can be and has to be understood in terms of evolution. This is probably the most difficult one to grasp. There’s a lot of talk about “religious biologists,” and in my opinion, this is only possible with a total divorce of any divine meddling with evolution. I already talked about intelligent design.

But the more important point I wanted to make about this is that all biological structures, on all levels, are created and explained by evolution – they are things that work rather than things that are perfect. They want to survive and propagate. They share similarities in structure with other structures or organisms which are descended from recent common ancestors – bats’ wings and humpback whales’ flippers. They share similarities in purpose with organisms that live in similar environments and have to protect their selfish molecules in certain ways. Sea urchins and cacti.

3.5) Human behavior can be explained in terms of adaptations in the ancestral environment. This is the basic philosophy of evolutionary psychology. Since behavior has a lot of abstract stuff in it like culture, I’d say this is pretty flimsy. For example, how does one begin to explain post-modern literature from an evolutionary perspective? It’s all very complicated. However, at a base-line, human motivations and instincts can and often have been worked into the greater framework of the amazing but misunderstood theory of evolution.

Further reading:

The Selfish Gene by Richard Dawkins

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One Response to Three and a half important facts about the theory of evolution

  1. Ian Hoke says:

    Be sure to also check out The Ancestor’s Tale by Dawkins. There is an amazing section of that book in which he outlines evolution in a certain kind of salamander that has taken place not so much over the dimension of time but over the dimension of physical space. It was a paradigm shifter for me. And even if Dawkins is that atheist guy, he writes argument with such precision that any budding writer should read him.

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