Tuesday, October 20, 2009

If we had some bacon we could have some bacon and eggs if we had some eggs

Evolution is all about the chicken and the egg. If you get the paradox, you probably get evolution. If you don't believe in evolution, I'll bet you're also puzzled by the paradox.

So which came first, the chicken or the egg? The paradox kind of disappears if you accept that a chicken and chicken-egg go hand-in-hand... they are so interdependent that it neither makes sense nor is relevant to consider one existing without the other. So it's not sensible to consider one coming first, without the other. They both evolved together. *

To be puzzled by the C & E paradox, all you have to do is imagine one or the other existing completely on its own. Imagine just a chicken... how was it born? Imagine an egg with no chickens... what hatched it? It is exactly these types of black-and-white narrow perspectives that leave evolution non-believers perplexed by all that evolution explains. Usually the standard solution is, "Something must have created it"; thus the need for a creator. But understand that they evolved together, in long sequences of many steps, none of which was such a leap as to be inconceivable to happen randomly, and the puzzle disappears. There is no step where a chicken appears without something very chicken-egg-like, and no step where an egg comes from something not very chicken-like.

Understanding evolution by looking at its current state and then working backwards, we're certain to come across many different chicken-and-egg paradoxes. If we assume that a particular species or trait "should" have evolved, then we are puzzled by all the unlikely events that brought it about. If we think that species are pre-designed, then we tend to think that only an intelligent entity could have created it. But evolution doesn't work to fit any pre-existing design. The design evolves along with the species. The design is never more than one mutation away from what currently exists. Which came first, the human or its design? They evolved together.

A typical chicken-and-egg-type conundrum involves taking 2 things that are dependent on each other, assuming one of them once existed without the other, then trying to figure out how the other came to be. Sometimes one of the dependencies isn't properly considered, either assumed to be a constant, or not considered a product of evolution, or not even noticed as a key element in the problem.

For example, one might ask, how did the human form "randomly" evolve into something so beautiful and aesthetically pleasing? Even our hands are works of art. If evolution favors functionally "fittest" traits, how did it also just happen to create such beauty? If your only answer is "Something must have planned it that way", or even "It must be a pretty big coincidence", then it may seem like evidence against evolution. But realize that our perception of beauty is also evolved. Our brains have developed to find the human form beautiful. You may equally validly ask, why did brains develop to find our form so attractive? Which came first, the human form or human perception of beauty? Chicken or egg? Of course, they developed together, hand-in-hand. If we had instead evolved to look like Darmok, then an evolved perception of beauty would have found his form as perfect as we consider the human form.

Questions involving the results of evolution must be asked within the context of what has evolved, to truly be answerable. Why do the conditions of Earth just happen to be so well suited to life as we know it? (Or the egg to that chicken: Why did we just randomly evolve into something that thrives here?) If the conditions on Earth were different (but still conducive to life), then life would have evolved differently, into something well-suited to those different conditions and vice versa. We can't answer any "How did evolution arrive at this unlikely point?" questions without realizing that what makes that unlikely point important is itself a product of the same evolution. Otherwise, it is simply a random point, as likely or unlikely as any other.

The Earth happens to be so well-suited to life as we know it, because life as we know it evolved within the conditions on Earth.

Evolution makes sense if you consider what may have existed before, and imagine how what existed later could have come about. If you focus on why certain things happened, it's not as clear. Asking "why" suggests there are predetermined reasons for evolutionary events, and having reasons leads to assumptions about some form of conscious thought involved in the process.

Because we tend not to naturally understand evolution, we create a need for and a strong belief in a supernatural creator. But once we've done this, even if we try to consider evolution from different perspectives, the assumption of the existence of a creator leads to further assumptions (such as predetermined reasons for events or existences) that make evolution confusing. Understanding evolution intuitively can remove one's intellectual need for a creator, but understanding evolution is much more intuitive when one fully suspends belief in a creator. This is another chicken-and-egg problem. Which comes first, understanding evolution without accepting it, or accepting it and then trying to understand it? Of course, they must come about together. The simple solution is to not try to require one side completely without the other.

Science: it's supercool!
-- Unknown

* To be technical, and to avoid trying to make an interesting paradox disappear by saying "I couldn't be bothered to think about it", I submit that the egg came first. For one thing, other animals reproduced using eggs long before chickens existed. It is highly unlikely that chickens ever reproduced in any other way, and later evolved to use eggs (there is probably proof of this). Birds evolved through various species of kinda-chickens, all using eggs in reproduction, before finally evolving after a very long time, into chickens. But which egg was "officially" the first chicken egg? I assume (without bothering to look it up) that species-to-new-species evolution can occur through many different mutations over many generations, and that there isn't always a perfect dividing line that says "this is a chicken, and it's parents are not-chickens". I assume that species changes blur across several or many generations, and it may not even be valid to isolate a single individual and say "this is the first chicken". This would be a clear case where the chicken and egg paradox is neither solvable nor relevant.

But if it so happened that a single distinct mutation separated a chicken from its not-chicken parents, that at some point in prehistory there was some kinda-chicken that wasn't technically-chicken, but which then evolved into a full-blown-chicken, then the technically-chicken egg probably came first anyway, because it is most likely that meaningful mutations resulting in the technically-chicken occurred during the genetic recombination of parental DNA, and less likely (I assume) that it occurred within the first or first few cell divisions of the kinda-chicken's life (either way, within an egg), and much much less likely that a grown kinda-chicken mutated in some key way that turned it into a full-blown-chicken. For certain, as this article is all about, it is extremely unlikely that a non-egg-laying non-chicken suddenly evolved the ability to lay eggs in one mutation or generation, all at once taking on that and every other characteristic needed to distinguish non-chicken from technically-chicken.

That kind of argument goes against the point of this article. Evolutionary changes occur on the level of random molecular changes, a tiny change in a single cell's DNA that expands to a larger change after a ton of cell divisions, some tiny defect that can be used as a new advantage, or at least results in a still-viable living creature. The "What came before that?" is nothing more miraculous or unexplainable than "The same kind of creature, less that one mutation." Big changes occur over generations and generations.

1 comment:

Erin said...

You need to go to grad school.

Or get a job.