Dani Banani:
I find your questions very worthwhile. I consider myself to have a reasonable grasp on evolution (it’s a vast topic) and a good grasp of the fundamentals of it, and a great grasp of the philosophical and theological ramifications.
This is quite an extended (and badly structured) reply to your questions. It’s intended to be informative, rather than argumentative, so I’d be grateful if those who disbelieve in evolution refrained from using it in their counterarguments. It covers an intended illumination of the process of evolution, the fundamental logic behind it, and the theological ramifications. It excludes the breadth and depth of evidence in favour of evolution and the counterarguments presented by the more fundamentalist religious, some of which are, in my own opinion, breathtakingly spurious.
I’d like to begin by asking you to consider the following:
1. If your parents have a particular, heritable trait, then you are more likely to have it than your peers
2. If that trait assists in survival or breeding, then you are more likely than your peers to have and raise many children who will inherit that trait
3. If that trait is disadvantageous to survival or breeding, you are less likely than your peers to have and raise many children who will inherit that trait
4. Therefore, those genes that cause traits that are advantageous to survival and breeding will become more common in each generation than its predecessor and those that cause disadvantageous traits will become less common
5. Over time, the population will accumulate advantageous-trait genes in a number of different areas; the correct height, intelligence, weight, social skills – always bearing in mind that extremes of a positive trait tend to have disadvantages (very tall people need more nutrition and may starve in a famine; also, they may be in worse danger of injury, so height will reach an equilibrium position; which is why, even though it’s way cool to be tall, there are no 10-foot men)
OK, so do me a favour now, stop and think for a minute about the claims I make above.
Given the above – I hope you get it – can you imagine a population
not
becoming “better adapted” over time?
OK. When we determined that the universe was expanding, and that there was no plausible reason that the universe should switch between expanding and contracting, we worked backwards and thought “huh. At some point, it must have been
well
tiny”
Similarly, working backwards, doesn’t it seem
inevitable
that our distant, distant ancestors were slower, more foolish, and weaker (The Neg-lympics!)?
OK.
How do new species arise? This is complex, and I’ve put together the following… well, fable, I suppose.
Imagine a land with about forty tribes (or herds) of a particular species. At the beginning of this tale, there is a mixture of slowish, thoughtful and of fastish, aggressive individuals. All the tribes on the island periodically intermingle. Then one day a river or iceberg or whatever appears and the east and west are separated (for simplicity’s sake).
In one tribe, a disease wipes much of the population. It happens to take most of the slower, more thoughtful individuals and leave the faster, more aggressive ones more relatively intact. This tribe becomes unusually good hunters. When mingling and interbreeding with nearby tribes on the east side of the island, over a hundred generations this inclination to be faster and more aggressive becomes commoner, as more are successful in this way, and so it becomes the norm as people move towards a carnivorous diet.
At the same time, on the west side of the island (btw I swear to god this isn’t a political commentary), a tribe begins to specialise in farming. They make a particular technological advance such that they can produce more through farming than any have before. The faster, more aggressive members cannot compete with the slower more thoughtful ones at farming, and even when they hunt, they do not provide so well. So the tribe (and by extension, the surrounding tribes) begins to tend more towards slowness and thoughtfulness and move towards an omnivorous diet.
Now, the east side is tending more strongly over another hundred or so generations towards carnivorousness. As people with sharper teeth become better eaters, so over generations people develop sharper teeth. As people with sleek, runners bodies catch more food, so over generations people develop sleeker, faster bodies. As the capacity to digest vegetation becomes redundant, less bodily resources tend to be dedicated to this and people begin to lose the
ability
to digest vegetation.
Meanwhile on the west side teeth become suited to a vegetarian diet, bodies become stolid and hefty, but they maintain the ability to eat meat although it’s not a primary source of food, as it is occasionally necessary during famines or in winter.
So, geology being what it is and all, one day the big MacGuffin separating the Westers and the Easters vanishes. Ooh, that tricksy geology. The Westers and Easters meet and mingle. There is experimentation with breeding between the tribes. While the genetics have not yet changed to the extent that the two sides cannot interbreed, there is a higher chance of miscarriage. That, however, isn’t the biggest problem. When the child was born of members of two tribes, obviously he’d be raised by his mother. So women in the West tribes would raise children who’d grow sick on vegetables, while women in the East would be mystified as to how to get their pudgy, slow-moving sons and daughters up to speed. It was just no good. Over time, inclination to breed with those from the other side of the island was an unsuccessful strategy, and so became rare, and became obsolete.
Two hundred generations on (and obviously I’m no expert, but probably more than 2 hundred) and there have been changes to the genetic make-up of the westers and easters. These include changes to the reproductive system – interbreeding is no longer even possible.
OK. So, it’s a crude demonstration, and an even cruder claim, but imagine for a moment that the tribes at the
beginning
of the story resemble Labradors, and the Easters at the end are like Lions and the Westers like Horses. It wouldn’t take four hundred generations but tens or hundreds of thousands, and obviously it wouldn’t necessarily take the above course or anything. But I hope it goes some way to both explaining how species might split off, and also how
arbitrary
the whole thing can be – it really is a ridiculous fluke that any species developed the way it did; including humans. There’s nothing “special” or “pinnacle-ish” about us. Nor does evolution work towards a goal; it’s a matter of who survives each generation, of cumulative changes, like the water in a river doesn’t plan to follow the course of the river, but goes where it’s pulled by all that influences it. If you catch my meaning.
I want to be clear on the matter of where new species come from.
In the Easter/wester example above, at no point is one generation a different species than the one before. However, the neither the end-point easters nor the westers could, if they went back in time, breed with their so-distant ancestors. The analogy I’m going to choose to call on is that of languages. Where do new languages come from? Languages change over time until they are entirely different than they once were and from other languages with the same root. At no point is what people speak an entirely different language than the day before, or year or decade or even century before. Yet, from Latin two thousand-odd years ago we’ve generated about a dozen distinct languages (species) each with several dialects within (races / breeds). Of course, different languages can merge, while different species cannot. That’s the relevant distinction. If you can breed with someone, you’re the same species. If not, you aren’t.
Now, macro-evolution is the process – to date and ongoing – whereby all species are adapted by their surroundings in a much more complicated way. There are splits and extinctions and migrations and all sorts going on all the time.
Why did the appendix shrink when it became pointless? Because it takes energy to support a full-size appendix. Energy that, when chased by a predator, when seriously ill, when experiencing a famine, when pregnant, has better uses elsewhere. People with smaller appendixes stood a better chance, so each generation had a smaller average appendix than the generation before.
I’d also like to state for the record that the separation of man into different areas round the globe was extremely recent, in evolutionary timescales, and the differences between races are very much skin-deep: Colour is the most noticeable, with vulnerabilities to certain illnesses varying, height, and dietary intake having a minor effect (relative commonness of lactose intolerance among Asians, for example). They’re shallow levels of differences; we’re fundamentally the same.
So, what does this mean for religion? Well, it has few options available to it. The problem is twofold: the beauty of and the evidence in support of evolution, and the biblical story of the Garden of Eden.
What was meant by the story of the Garden of Eden, of Adam and Eve and all that jazz? If it’s a claim that that’s how God actually made all life, then there’s a strict opposition between the claims of the bible and the claims of the scientific community. You gotta choose between God and logic. But it’s not so simple as that. Jesus spoke in parables; he never claimed that there ever actually
were
any good Samaritans.
Genesis doesn’t have a preamble. What if it’s not there to explain
how
God created life, but why? To explain why things are the way they are; why women suffer in childbirth, why men must work for food, why serpents lack legs: because God willed it so, because all these beings have done wrong in some way. Heck, if life on earth is separate from the kingdom of Heaven, and sin constitutes separateness from God, isn’t sin unavoidable? So this could be a parable of God’s decision to have a land that is not blessed by his continued presence, and which will have sin,
but
that he still reserves the right to call the shots as he sees fit.
Or it could be a simple origin myth, like those found in Greek and Norse mythology. Heck, read Just So stories and the early parts of Genesis start to make you feel very uncomfortable. Humans tell stories. It’s what we do. What if somebody wrote an untrue story about the origins of man that somehow – completely innocently – got folded in to the Book Of Truth, the Holy Bible of God? Priests aren’t all-knowing, you know – we can tell by looking at those that we have today – maybe one was once fooled by a conman.
Maybe God created life through evolution. I mean, he’s not just very, very smart – he’s omniscient. Stands to reason he could guide the seemingly-random forces of evolution to the result he wanted. A nudge here, an extinction there… and all so that we would arise. Pretty flattering, no? And, of course, it’s pretty complicated and confusing, and the people 3000 BC weren’t ready for it, so he explained it in simpler terms.
Terry Pratchett coined the term “Lies to Children”. You start off telling them that atoms are like really, reeeeelly small soccer balls because it’s simple. Then you expand – well electrons whiz around the nucleus following set paths – like an orbital path. Then, when they study at a more advanced stage, you tell them, well, we
think
the electron isn’t
actually
anywhere, but have a potential, a likelihood of being in certain places.
In this scenario, yes, Genesis would be “Lies to Primitive Humans” but the point is not all lies are given with the purpose of deceiving; Lies to Children are given with the intention of explaining as best you can to a limited person. Not exactly False Witness.
So, the most popular ways of dealing with evolution by religious folk:
1. Evolution is a lie propagated by Satan / Evil Scientists / Well-meaning but wrong scientists, and the Bible is the true, 100%-accurate Word Of God
2. God guided evolution, and the Story of the Garden of Eden was never meant to be taken so literally
3. God guided evolution, and the Bible, while inspired by well-intentioned and holy men, contains some errors
4. God’s not like people. It’s a force, a fundamental spirit throughout the universe. Jesus was a good man who presented good morals to live by; by observing the good bits of the bible and ignoring the bad, one may assemble a worthwhile ethic to live by. Best not to get hung up on what exactly is “true” and all that, but humankind evolved within the Universe (kind of pantheism)
5. Evolution just happened; doesn’t need a mastermind, it’s self-sustaining and don’t multiply entities without necessities please. God didn’t decide it. While the Bible contains some truth, so does “The Time Traveller’s Wife” – it’s essentially a work of fiction, a result of the delusions, fantasies and lies of “Holy Men” through the ages. There is no God.
In case you’re curious, I come down in box 5. If you’ve been raised a creationist, I’d expect you to be most comfortable with box 2, possibly box 3. You must understand, I grew up not even hearing of creationism. Where I come from, if you’re religious you pretty much believe 2 or 3 (or both, you know). If you’re spiritual you believe 4 and if you’re an atheist, strong or weak, you’d tick box 5 if you had to pick any (because these boxes are crude descriptors).
I hope that this has illuminated the scientific beauty and underlying systems of evolution (I’ve opted to exclude descriptions of how the theory has changed and been supported time and again by evidence, not to mention the scientific enquiry engaged in with the presumption of evolution which keeps being successful as you would only expect it to if evolution is true). I hope I’ve also adequately explained why this doesn’t necessarily explode peoples’ faiths, although those who believed in God merely because “how else did we get here?” are freed from belief by the “theory” of evolution. If you believe in a God of the Gaps – a kind of Duct-tape to cover over all the stuff you don’t understand – then evolution reduces your need for God. However, evolution only actually
contradicts
fundamentalism. There are other ways to believe, such that evolution is a happy coexister to God.
I’d like to wind up, for those of you who are familiar with evolution and found this post at best dull, at worst and naïve misstatement and a “lie to children” itself, with this, from a previous co-worker of mine:
Joe: If evolution is true, then how come chimpanzees stopped evolving?
Me: [stunned silence]
Joe: [triumphantly] See, you can’t answer!
(You won't see them if you read the NIV translation, as the translators there have worked that problem out with some "creative" translating of a verb tense.)
