Wednesday, May 27, 2009

Interconnectedness

So, I haven't posted in a while. Mostly because, as I said two posts ago, I've been crazy busy trying to help run my wife's business--how she did it for so long by herself, I'll never know. She's amazing, that's all I've got to say about that.

Partly, though, another reason I haven't gotten back on here is because I think I pigeonholed myself into too tight of a corner; I didn't really find my life interesting enough to blog about, so I wanted a specific theme for the blog... But now I feel like, if a post isn't about Buddhism AND naturalism, I shouldn't bother posting. That is, of course, silly; it's my blog, I should post whatever I damn well please, and if you're not interested, you won't read it. Not like I'm inconveniencing anybody!

That said, I'd like to talk about Buddhism and naturalism ^_^

I've been learning a lot about genetics, lately. Cellular biology is a passion of mine--a purely amateur passion, for now, though I hope to go back to school for it one day--and genetics are naturally integral to any understanding of microbiology. Now, everyone knows that genes have something to do with DNA, and DNA is the code in your cells that builds you, right? Hollywood Science 101, and it's more or less right. But what actually goes on in the DNA at the cellular level? While your body is being built and maintained, macroscopically, what is actually happening to those strands of sugars and acids called DNA?

Allow me to give you a brief layman's version, as best as I understand it (being a layman, myself), and work it around to the Buddhist notion of the interconnectedness of all things.

DNA is code; I think everyone knows that. It tells your cells what to make, how big to make it, when to stop making it, and where to put it when it's done. (Advanced Biology, meet Layman's judo chop!)
Every cell in your body carries, in its nucleus, the entire code for every part of your body. The bits of code for specific parts are called genes; and the grand totality of the information for building your whole body is called the genome.

Now, when I speak of code, what I mean is that DNA is like a type of binary language that a computer would use--every amazing thing that your computer does is because a super-long string of 1's and 0's told it how to behave. Well, DNA is twice as expressive as that; rather than 1's and 0's, it has A's, G's, T's, and C's. A special enzyme runs across a string of DNA like a blind person's finger across braille, translating the GATC's as instructions. And so you can picture what I'm speaking of a bit better, I know you're familiar with the double helix shape of a string of DNA--take it and flatten it out into a ladder in your mind's eye. Now, each rung is made up of two letters, one on either side. And here's a little tidbit that will become important in a minute: just like a magnet always has a north and a south, each letter will only ever fit across from one other letter--G's with C's, and A's with T's. When the enzyme "reader" scans along, it's only looking at one side of the DNA... because the opposite side is always going to be the exact same, just in reverse!

Don't worry, I'm getting somewhere.

So, when a cell receives the chemical signal that it's time to divide (you know, asexual reproduction), another enzyme slices through the DNA's ladder rungs like a zipper, separating a single strand into halves. And since each letter will only ever go with one other letter, it's easy enough for those two halves to be fitted with the appropriate nucleotides (the freefloating letters, if you will) and so you have two copies of one original genome. Each genome goes to an opposite side of the cell, and--sploot!--the cell splits in half, creating two new cells out of one old one. It's kinda poetic, ain't it?

Now, this copying is happening over and over, constantly, within your body. With the exception of a few rare mistakes, every cell in your body replicates, over and over, the exact same set of codes that you started out with when you were just a blastocyst in your mother's womb. From the moment of conception til the moment of death, your cells--whether they're in your skin, your heart, your brain or your spleen--are all expressions of the same genome; like color is the expression of the same quanta of light, just in different wavelengths.

But that got me thinking... what about that little bundle of cells called an embryo? It didn't just pop out of nowhere. It starts out as a single cell, too: an egg. And this egg has exactly half of the mother's genome (the specific genes selected randomly), and the father's sperm has exactly half of his genome, also selected randomly. These combine together to form you--but these genes you're replicating didn't originate with you, they don't belong to you--your mother and father, respectively, were replicating those exact same genes for decades before you ever existed. Which, of course, means that their genome is a constantly replicating amalgam of their parents' genomes, who faithfully replicated their parents', etc. Each time these genomes get replicated into egg or sperm cells, they might contain a few trivial mistakes, but overwhelmingly they stay the same, and have stayed the same for the last 100,000 to 200,000 years. Yes, friends, our similarities are more than just superficial--they literally run right into our marrow; into the very fiber of who we are.

Which means, of course, that if one were to look back at our closest ancestor which split off into a different species, we would see that we still replicate the same genes they had almost identically, and our relatives also still replicate those same genes, almost identically. This is, in fact, exactly what it means when you here someone refer to the fact that we share 98% of our DNA with chimpanzees--we literally are still copying 98% of the same patterns, using the same sugars and acids to build the same little twisted ladders, over and over and over again.

We replicate 85% of the same genes that mice use. We have half the genome in us that our shared ancestors also gave to fruit flies. And 31% of the genes in our bodies are the same ones being duplicated right now in a simple, unicellular organism like yeast.

I remember thinking how bizarre it was that some sea creatures reproduce by budding. Like a fungus, they start growing a little clone of themselves, like a little mini-me, off their shoulder, then they cut the little squirt free and start the process again. No sex? No internal gestation? How weird!
But what is reproduction, really? From a gene's-eye-view, sugars and acids stack up, split apart, and copy themselves, over and over. It doesn't care what kind of cell it's in; it doesn't care if the cell is located in one body or another; it stacks up, splits apart, duplicates. For over half the age of this planet, those molecules have duplicated. They've changed a great deal--from the basic need to replicate, all the way into a sentient being that can gaze upon distances astronomic and microscopic and wonder at it all... but it's all connected. From the carbon forged in the massive hearts of stars, to the eye that receives the light shed from those stars' contemporaries.

Ponder the intricate web of it all. Let it make you humble, and let it make you proud, to be part of such a magnificent process. And let the love you feel for your children, your parents, your siblings--knowing that they are literally a part of you and you of them--extend not only to all humanity, but to all life in the world.