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Tuesday, July 23, 2019

Impossible yet abundant: Pondering the marvel of life

Photo by Tyrel Johnson on Unsplash
We were westbound on I-80 just past the inlet of Echo reservoir. My eyes were lazily scanning the hills when it hit me. Here, in one of the most arid of the western states, we were nevertheless surrounded by living things. If I could catalogue every distinct life that fit into a single glance, it would be unimaginable in both number and variety.

In a single frame of vision, there were untold varieties of grasses. There were millions, perhaps billions, of discrete plants of sage and mushrooms, grain and weeds, flowers and trees. Each one an absolute stunning marvel of engineering and unique expression of its species.

There were deer and horses, antelope and rabbits, field mice, muskrats and toads. How many varieties of worms, slugs, insects, spiders and flies played in the tapestry only God knows, and I mean that sincerely and reverently.

Photo by Pree Bissessur on Unsplash

Consider, also, the microscopic organisms. On average, one ton of earth’s soil contains 100 quadrillion of these microbes. At six feet deep, there are about 7.5 million tons of soil every square mile. And I was taking in dozens of square miles in a single glance.

What dawned on me that day is the simple fact that all this life was packed into a single moment of a single day of a single citizen on a planet with 7 billion people. There were 100-times more living organisms before my eyes in that moment than there are stars in the universe.

All that life, and yet, when you step off our planet and scour the universe—as we have been doing for 60 years—we have yet to find even one single instance of life anywhere. Not a bug or a weed, neither algae nor an amoeba has ever been found. We haven’t even found a planet that could theoretically support life.

I make no claims about what we might find in the future. I know of no scientific or theological reason why biological life could not be found somewhere else in the universe. But the stubborn fact remains. Even the most optimistic probability models find it practically impossible.

All of which underscores how astoundingly special is our living world.

For the last century and a half, preachers of the enlightenment have been working on a project to explain all this life by means of undirected, random changes vetted through an ongoing battle for survival. The technical term is “Natural Selection.” More popularly, it is known as the Theory of Evolution.

I have been critical of this theory in past articles, but I am not going to talk about it today. Today’s topic considers a prior question. It’s about a world before evolution was even a possibility—a world without life. After all, before the fittest can survive, it must be alive in the first place.

While almost everyone has been taught that every living thing evolved from a single cell being, no one can tell you how that imaginary one-celled creature came to be. Most do not even know the scientific name for how it might have come to be. That name is abiogenesis.
Photo by Elevate on Unsplash

Abiogenesis discusses how life happened in first place. Every form of life carries information and moves toward self-preservation, repair and reproduction. But in a purely chemical world, there is nothing but randomness. How did matter ever arrange itself to become alive in the first place? What would it take for a random stew of chemicals to form the first living cell? After a century of theorizing, there is no single, generally accepted model for the origin of life.

The famous Miller-Urey experiment of 1952 created a highly controlled laboratory environment to synthesize a few of the amino acids necessary for making the proteins necessary for life. Scientists thought they were well on their way. Now, 67 years later, they have progressed no further. To this day, nobody knows how to link these amino acids together to make a protein in nature. Much less can they build an impossibly complex cell.

A living cell is an astounding assembly of molecular machines. Each machine performs amazingly complex and specific functions that contribute to the total life and well-being of the organism. The more we learn about the intricacies of the cell, the more marvelous it is.

Part of what we have learned is the interlocking nature of these molecular machines. They are made of multiple parts—none of which could possibly benefit the organism unless they are all assembled in exactly the right way. Scientists have dubbed this phenomenon, “irreducible complexity.” Examples are found everywhere.

On top of that, the machines themselves only work in combination. Molecular machines designed to transport material only work if there are cells that build a thread-like road on which the transporter can “walk.” Either without the other is useless. The complexities only increase from there.

For life to happen, it’s not enough for a few of these irreducibly complex machines and machine-systems somehow to have come together. At the same time they came together, the living cell also needed other machines to make replacement parts. In a living being, molecular machines are constantly being assembled, wearing out, breaking down and being replaced.

The constant manufacture of replacement cell parts is itself directed by an entire system of code and code readers. We call the code, “DNA.” A single Amoeba dubia has 670 gigabytes of information coded in its DNA. But this cannot be read and translated to the rest of its molecular machines without the proper reading and communicating machines.

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 that cell knows how to make machines that duplicate the DNA and divide into another cell before it dies, all this information and complexity would be lost in a single generation.

Life is an amazing thing. This brief outline only begins to scratch the surface. Abiogenesis is far more complex and interconnected than I can hope to describe in a single article. In fact, it probably exceeds all the powers of your imagination as well. Before we even start the discussion of evolution, life itself is a thousand times more unlikely.

Yet, despite the impossibility of life arising by random processes, we are utterly surrounded by it. These two facts are worth pondering together.

While you are pondering how these two things can simultaneously be true, 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 ponder these facts.

Life is good.

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