Milepost 12 on I-80 westbound has long been one of my favorite vistas. There my hometown of Evanston comes into view. In a single glance, my eye takes in miles of the beautiful Bear River Valley. The valley is alive.
It only recently struck me that in this single valley, there are millions, perhaps billions, of discrete plants. Each one is an absolute stunning marvel of engineering and unique expression of its species. And that’s just the flora.
The fauna ranges from big game to tiny rodents, from centipedes to slugs. Then, there are the microorganisms. On average, one ton of earth’s soil contains 100 quadrillion microbes. A single glance from Milepost 12 scans 100 times more living organisms than there are stars in the universe.
This stands in stark contrast to another fact. After 60 years of scouring the universe for other signs of life, we’ve come up empty. Neither a bug or fungus or amoeba has ever been found. We haven’t even found a planet that could theoretically support life. Planet Earth is teeming with life in an otherwise sterile universe.
For the last century and a half, preachers of the enlightenment have been trying to account for life by theorizing that undirected, random mutations are selected through an ongoing battle for survival. Natural selection is more popularly known as evolution.
This theory holds that all life began with a single-cell organism that has been transformed into the amazing diversity of life on earth. Whether you find macro-evolution plausible or not, the entire theory hangs on an imaginary protoorganism that somehow came to be alive.
Our children are steeped in the language of evolution from children’s books through graduate school. But if no one has ever explained to you how that original protozoa came to be, it’s because, there is no single, generally accepted explanation for abiogenesis.
Life moves toward self-preservation, self-repair and reproduction. But in a purely chemical world, these life forces do not exist. Rather, purely external factors determine when atoms combine into molecules and when they fall apart. In a world without life, how did the first life occur? That’s the question of abiogenesis.
A living cell is an astounding assembly of molecular machines, each machine performing specific functions necessary for the survival of the cell. Each is made of multiple, interlocking parts that are useless to the cell unless they are all assembled in exactly the right way. This is called “irreducible complexity,” and it’s found everywhere.
Besides that, many machines only work in combination. For instance, molecular machines designed to transport material can only “walk” on a molecular road built for the task. Either without the other is useless. The complexities only increase from there.
For life to happen, it’s not enough for the perfect combination of irreducibly complex machines somehow to have come together. There must also be machines to make more machines. In a living being, molecular machines are constantly being assembled, wearing out, breaking down and being replaced.
All this activity must be coordinated by gigabytes of information written in a special DNA code. This code can only be read by another set of machines built for that task. It’s so detailed that the DNA in a single Amoeba dubia contains 670 gigabytes of information.
Finally, all of these machines and all of this information must be protected by a cell membrane. Without it, the earth’s oxidizing atmosphere would destroy everything instantly. But the membrane cannot be just a simple barrier. It must have dozens of different gates that let in specific chemicals at specific times while letting other chemicals out before they destroy the cell from within.
If all of this can come together in a random way, you have a living cell—but only for a few seconds. Unless it knows how to make other machines that duplicate the DNA and produce another cell before it dies, it can pass none of this information on to another life. Abiogenesis must start over again from nothing.
Life is an amazing thing. This brief outline only begins to scratch the surface. Abiogenesis is far more improbable than I can hope to describe in a few words. Before we even start the discussion of evolution, consider that life itself is infinitely more unlikely.
Despite its impossibility, we are utterly surrounded by life. Ponder that fact. While you are considering how these two things can be true simultaneously, you have good reason to laugh out loud. You are alive.
You are an impossibly complex and wonderful organism planted in the middle of a world filled with equally impossible life forms. And you, above every other living creature, have this additional gift: you can read these words and think on these facts.
Life is good.
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