Saturday, September 22, 2007

On the Third Day, Part 2: Fencing a Fluid, Sowing a Seed

Have you heard the story of King Canute? About a thousand years ago he ruled Denmark, Scandinavia and England for about twenty years, and his reign sounds like it was relatively stable and just. He's famous for holding court on the beach one day, staring out at the waves and commanding them to retreat. They didn't retreat -- as powerful as he was, he couldn't mold the wind and waves with his word. That may have surprised his courtiers, but it didn't surprise him in the least. That's why he dragged all of them down to the beach, for that precise object lesson, that as powerful as King Canute was, and as large as his kingdom was, he couldn't turn back the waves from their borders, so don't expect too much from him. It wasn't an ego-centric display (if it was, all he had to do was make sure he held court when the tide was going out, right?). It was always intended to be a statement of his own limitations, and of what true power entailed.
The limits of the ocean were set earlier in this day, according to Genesis. This was a powerful act in the ancient world, where the sea was the embodiment of danger and capriciousness, something that could hide monsters, destroy ships, drown sailors. Appreciating the power it takes to corral the sea requires a full appreciation of the power of water. I think of it (naturally!) on the atomic scale. Water is unusually powerful because it's small but also very unbalanced: its two hydrogens are in a constant tug of water with its oxygen, and the result is a molecule that sticks together extraordinarily well despite its compact nature, so that it can sit in a glass as a liquid instead of spreading out like a gas. A single water molecule can be a chemically powerful tool with two "sharp ends" that can do chemistry; a mass of them forms the oceans, which we still haven't explored; the expansion and contraction of water can crack concrete or ruin a house; a frozen mass of water can gouge out valleys, leaving gigantic skid marks behind. Water can do a lot of things, and it doesn't care what you say to it. According to Day 3, it does care what God says to it.
So this is where life came about, first in this ocean and then on dry land. To do so it had to perform its own microscopic version of King Canute's proclamation: it needed to have boundaries set within this huge mass of water so that its chemical reactions wouldn't float away and disappear into the far reaches of the sea. This is the knife-edge that life has to walk: we need water for its chemical power, but its chemical power can break us down. Sam, about a month ago you insisted on getting some sugar in a cup, adding water, and watching it disappear. Congratulations on your first chemistry experiment, that sugar dissolves. And that's what water does to most everything, it disperses it and breaks it up. Now, there's certain advantages to the breaking up, because fluids have certain advantages. For example, it's very easy to send sugar from your stomach to your muscles through the blood. Also, once you have one little living chemical factory set up, you can make another one fairly easily. The trick is setting up the factory in the first place, like trying to pitch a tent in a driving thunderstorm.

What's also remarkable is that we keep finding evidence that as soon as the earth cooled enough, some kind of life popped into being. In the 1950s, we had rocks with 600 million-year-old life. In the 1970s, there was evidence for 2.5 billion-year-old life. Recently, there's been several lines of evidence for 3.85 billion-year-old life. To quote Bill Bryson, "Earth's surface didn't become SOLID until about 3.9 billion years ago. 'We can only infer from this rapidity that it is not "difficult" for life of bacterial grade to evolve on planets under appropriate conditions,' Stephen Jay Gould observed in the New York Times in 1996. Or, as he put it elsewhere, it is hard to avoid the conclusion that 'life, arising as soon as it could, was chemically destined to be.'" Let me put it another way: the seed of life came about on Day 3, just as the oceans reached their current size, just as the sea and dry land were formed.
Life was springing up like flowers in a field as soon as the earth cooled, and the key act was building the wall needed to enclose it. That wall is the cell membrane, which you've likely seen in biology class. Cell membranes are made up of oily molecules that look a little like soap and act a little like water: they are unbalanced too, but they are very long and skinny, and they line up automatically like slats in a fence, with an "outside" and an "inside," just like bubbles. Aidan's favorite thing right now is hunting down bubbles, so you boys already know how soap forms bubbles in air: this isn't too different from that, just in water. You enjoy bubbles because you can run around and smash them with the slightest touch. A finger might be able to do that, giving you a sense of power as a three-year-old ("Did I ever tell you that you are very strong?"), but atoms are so small that to them, the "cell bubble" is hard as iron. So oil makes a great fence, but also notice how it is still a fluid fence, how one oil puddle can merge with another. Bubbles can bump together and join, and they can split apart too. Everything's doused in water and can float around on the scale of the simplest life forms.

Some creation event happened, and just had to happen once, to make life in a soapy bubble. You need a way to burn energy and to maintain yourself, inside a fence, and you have life. Because cells are like bubbles, once one was established and chugging along, consuming energy and maintaining its insides, all it had to do was make two of everything it needed (like a tiny Noah's Ark? the metaphor breaks down!) and it could blow another bubble from inside it. Voila: you had a father cell and a son cell. I'm sure the son took after his father, or to put it another way, was of the same "kind" as his Dad, just like each of you looks like me (and even more so as you age, I'm afraid). Good thing you look like your mom, too.

Wait a second. Aren't you raising your hand yet? You should have the urge to stop me here, because I've just glossed over a major point. How did all these chemical reactions get put into a single bubble? To keep the chemistry going, some chemicals had to cross that iron fence of a membrane, so how did they do that? What kinds of reactions were these? All I can say is that I have the same questions you do. The initial formation of life is, like I said, a case of walking a knife-edge, and how all that complexity got into one place we honestly have no idea. Maybe this is a secret God's keeping to himself. Maybe he intervened with a miracle there, because life certainly qualifies as a miracle. On the other hand, maybe he caused life to spring out of the mix of elements naturally, so that life was set up at the beginning and didn't require any tweaking to result. If that latter case is true, then maybe he'll let us figure out how he did that trick. It's still amazing, to live in a universe that begets life so easily, in that case. I do know he set a lot of other stuff up beforehand, so I wouldn't be surprised if he set this up too. On the OTHER other hand, we don't have any evidence for other life yet. I'd say that's for him to know and us to find out.

Let me quote a physics friend of mine: "Either there's life somewhere else in the universe, or there's not. Either way, it blows your mind."

What I know is that we have evidence for very, very old life that must have been complex enough to eat, move, and reproduce, right away. That's the same image you get from the latter part (the afternoon?) of day 3:

Then God said, “Let the earth bring forth grass / the herb that yields seed / and the fruit tree that yields fruit according to its kind / whose seed is in itself on the earth” / and it was so / And the earth brought forth grass / the herb that yields seed according to its kind / and the tree that yields fruit / whose seed is in itself according to its kind / And God saw that it was good / So the evening and the morning were the third day.
We haven't got to grass, herbs and flowers yet, but this tiny bubble of life is definitely a seed. There are some differences in order between Genesis and the scientific consensus. Those don't bother me. The point I'm trying to make here is that you can use the days in Genesis, in order, to talk about the scientific side of creation, and it tells a true story. More about this in Day 4, because if you think you have issues now ... but let's not get ahead of ourselves.

Let's talk about the seeds in this passage, seeds that lead to life and allow it to keep on keepin' on. For all the fluidity to life, there's also a remarkable stability. You can live on hamburgers or on lettuce, and your body pretty much stays the same (if you find a minimal amount of essential vitamins somehow!). You are recognizably "you," but you're also always growing and changing. So life is defined by fluidity on the one hand, and stability on the other. Something that mutates your DNA is a dangerous thing because you need your DNA to stay the same, to stay stable: it is the essential component in both telling your cells what to do and in passing on these instructions to your kids. So don't mess with it unless you have to!
The most important scientific observation of stability, which we get from this passage as "reproduction of kind after kind" was made by a monk, Gregor Mendel. He was a gardener, so he bred plants, and systematically noticed what happened when he bred different plants. Each of these produced "after their own kind": peas made peas, flowers made flowers, of course. What Mendel's eyes caught was that some traits got passed down in different amounts, some traits would always dominate over other traits, some traits couldn't be seen but then would show up in the offspring of two particular plants. In short, Mendel saw some of the details in how plants made other plants "after their own kind," and he worked out some rules that provide "stability" within the "fluidity" of these changing traits. He got some attention but had to wait for twentieth century for this work to find its true importance. What he was seeing was the interplay of two sources of DNA, and that DNA splicing and recombining in predictable and powerful ways. To talk about how exactly, you need a genetics class, but the point for now is the stability of predictable rules of heredity, along with the stability of the message that DNA: the pea plant's essence, down to the traits.
But obviously some things change with DNA and heredity. You boys may look like me but you are most assuredly not me. Sam looks like equal parts mom + dad, and Aidan looks like neither (although he has a striking resemblance to his mom's family). Some things change from generation to generation: You need to change, and you need to move. So DNA is very stable and can carry changes from generation to generation, but when you look at it close up, you see "islands" of stability and also a surprising amount of fluidity. For example, some DNA looks just like an old, broken-down virus. In fact, there is more DNA in your cells that looks like an old, broken-down virus than there is that looks like typical, useful genes. It looks like viruses have been integrating themselves into our genomes, like little meteorites hitting a planet and leaving tiny craters behind. You can find these yourself with a DNA sequencer. (I've got one in my lab, by the way, for trying stuff like this if we can work out the safety issues!) That's a change, and it's a pretty big one. More than just a letter or two here or there, it's whole paragraphs of change.
Looking at the tiny bacteria that are the simplest form of life, you see that DNA itself is a fluid molecule, in that it physically flows around inside the cell. It is a long string of information that floats around in the bacterium. If you collect the DNA in biochemistry lab and accidentally shake the tube too hard, you can shear the DNA into bits, so be careful. Bacteria actually send messages to one another using circular snippets of DNA, like little frisbees of genetic info they cut out and toss back and forth. This is how resistance spreads in hospitals if one doctor gets a little too loose with antibiotics: once one bacterium figures out how to survive, it "emails" all its friends with the "cheat code" and then you have antibiotic-resistant infections. Bacterial DNA is so fluid that essentially bacteria share one big gene pool. "It's rather as if a human could go to an insect to get the necessary genetic coding to sprout wings or to walk on ceilings." (Bill Bryson, p. 304) There are even some processes in our own immune cells that shuffle DNA around in big chunks, a bit like these bacterial frisbees. Not to mention, HIV works by shoehorning its own viral DNA into yours, and then using that cell to make more baby viruses. If that's not violation, I don't know what is. But the main point here is that DNA is fluid enough to allow all this chemical traffic.

So you've got the stability of heredity, but also the fluidity of traits that can change, or "hide out" for generations. You've got the stability of DNA that makes a son like his father, but also the fluidity of viruses that have sidled up to our genomes and slipped in a big chunk of DNA to hijack our cells, more times than you can imagine. Compare this to the first half of Day 3: the earth is stable, as stable as the ground we stand on, yet there is a fluidity underneath it all, a fluidity that tells of the creator's energy and dynamic nature, and one that shapes our world.

Even the earth is fluid. If that's so, then it's reasonable to see that life, and its chemical foundation DNA, is decidedly more fluid than the earth. Don't think of DNA as a rock, it's more like a river.

For a long time, the earth was dominated by bacteria. Most bacteria kept the same DNA and kept reproducing after their kind. Once in a while the fluidity in DNA would result in a bacterium that did things differently, maybe a little differently, maybe a lot. Eventually, some bacterium got a protein that would change when light shone on it, and this change could be put to use in making a molecule that couldn't be made otherwise. This allowed the bacterium to "eat" light and live off the sun (photosynthesis), and to spit out this unusual molecule. Because these bacteria could grab energy from the sun, they could live off of carbon dioxide and spit out carbohydrates and oxygen, even though they're spitting out something more reactive* than they're taking in. With photosynthesis, light energy could be stored as matter.

As the oxygen bubbled into the atmosphere, it didn't stay there for long. First it combined with excess iron to form orange rust, which sank to the bottom of the sea. You can find these deposits by digging down, as great brownish bands of iron oxide, which you can refine and put to use. These are evidence that the earth slowly rusted for millions of years.

After the iron deposits, we begin to find interesting fossils: large flowery mattress-type things called stromatolites, after the Greek word for "mattress." The bacteria started to make surfaces that would stick together. When sand got caught in the stickiness, it would harden into something a lot like concrete, and colonies of these bacteria would form the weird, artsy fossil structures we find today. These were thought to be lost forever till 1961, where people began to find living stromatolites in remote corners of Australia, then Mexico. They're easy to miss because they just look like rocks:

But these rocks spit out oxygen bubbles (it's alive!!). For a long time, perhaps 2 billion years, this process was the most important thing happening on this planet. Stromatolites releasing tiny bubbles of oxygen. (Maybe Don Ho was onto something.) Slowly, eventually, this tiny action completely changed our atmosphere and charged it with oxygen. Oxygen was a chemical gift just waiting to be opened, because independent life can be built around using that one molecule, including, obviously, ours. There was so much oxygen that more complex life could use it to grow, and didn't need to be fixed onto the sun like the photosynthetic organisms. So stromatolites ultimately made it possible for college professors to be able to survive holed up out of the sun in a dark office, typing about stromatolites. Hooray for stromatolites.
There's an interesting word chemists use when gas bubbles out of a liquid. I guess "bubbles" doesn't sound impressive enough, so we say the gas "evolves" out of the solution. If gas evolved from the stromatolites, then the atmosphere evolved, too, although I'd have to use "evolution" in the sense of "change" for that. Both of these uses are probably not what you first think when you hear the word "evolution," but they're both correct uses of the word. More on the rest of it later.

Since we're putting all these processes somewhere between the poles of "stability" and "fluidity," I think it's important to point out that science itself is inherently fluid, but also stable. Science, especially at first, is fickle and will change its mind back and forth. Plate techtonics was still mocked in textbooks in the 1950s. The exact date of the cooling of the earth is still up for grabs in terms of millions of years, but not in terms of billions of years. Don't let the incidental "fluidity" fool you, because these debates take place around established points that are very stable. Even though it's only a hundred-year-old theory, I don't expect the Big Bang to change anytime soon, in part thanks to the background radiation observation in Day 1. Remember, I think that's a good point for theists. I also don't expect to be find out that the earth is young, because there's just too many different experiments that make it look old, mentioned in Day 2. One experiment is a debating point; 100 experiments make a theory that can stand the test of time, if interpreted properly. And there's the really fun part, the offspeed pitches of science (in baseball language), the issue of interpreting results. Don't be afraid to debate anything, but do be aware if there's 100 experiments that point in a certain direction, you're going to have to have a similar amount of evidence pointing the other way to convince most scientists -- or something truly special about your explanation. It had better cure cancer or something!

The amazing thing to me is that this evidence I've been running on about for three days now, this evidence can be fit with Scripture. Some interpretations have to fall away as a result, but the essence remains and it assembles into a "true story." This is powerfully deep to me. Even when what you thought was stable falls away, God will remain your stability. His reality is stable even when the continents shift:

God is our refuge and strength / A very present help in trouble / Therefore we will not fear / even though the earth be removed / And though the mountains be carried into the midst of the sea

If you have faith as a mustard seed / you will say to this mountain / 'Move from here to there' / and it will move

The fact that God is the creator of all is what Genesis says. I'm trying to fill out the details with my crayons, although I must warn you that, like you, Sam, I've never been too good at coloring within the lines. But I'm telling you, if you want a stable, simple text that will stand the test of time, read Genesis, and know those words by heart, just be open (fluid!) in your interpretation of the words. If you want to delve into more than that, then keep reading my letters, and use them as your own starting point, as you wish. The real stability is found in the words of Genesis, not my words. The real rock is the truth that God made all this, and it was very good.

So continents crashed, mountains shifted, oceans formed, bubbles replicated, oxygen bubbled, and the atmosphere evolved. I'd call that a day, and God did too. It was evening, and it was morning. The third day was done.

* Technically, this should be "oxidative" rather than "reactive" to point out what kind of reaction we're talking about, but I believe that's a technical point. I thought about leaving it in just to see if I'd get any indignant chemists, but that would be tricksy of me. Besides, there's already enough indignant chemists in the world!

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