The Great Chain

The Great Chain

Friday, September 3, 2010

Why I Don't Believe Part 5 - Biological Evolution

Life is literally everywhere on this planet. It covers the land. It seethes in the oceans. It suffuses the air. The entire surface of our planet is quite literally alive. A carpet of living, breathing, replicating things that have colored oceans blue, the land green and changed the composition of the sky. Even environments that look utterly barren are coated with life. When you look in the mirror, you are seeing not only yourself, but you and hundreds of billions of other living things crawling all over your skin and seething in your gut. Indeed, every square centimeter of your skin contains some 100,000 microbes, all working, synthesizing energy, reproducing in complete anonymity, completely beneath our level of awareness.

Simply because life is not readily apparent to us, however, does not mean that it is not there. Every movement we make through the apparently empty air is a movement through a sea of life. We are quite literally surrounded by life every moment of every day. Indeed, life is SO prolific, and SO adaptable, that in even the most inhospitable, even the most unimaginably challenging environments, life somehow scratches out existence, no matter how meager.

Life persists in the perfect darkness, sub-freezing temperatures and absolutely crushing pressures of the cold seeps located at the ocean floor. It thrives in boiling water and pitch blackness clinging to the edge of a undersea volcanoes. Even when trapped under a mile of ice, or confined to pools of sulfuric acid deep inside the blackest caves, even in the cold, pressureless depths of the void of space, life persists. The fact that living things are capable of adaptation and existence in such extreme environments, that life is capable of survival even in the most inhospitable environments is a testament to the power and persistence of matter. Once matter becomes organized, once it obtains purpose, it is virtually impossible to dislodge. And this persistence of life, the power of matter to organize itself and maintain its existence even in the most impossible conditions strongly suggests that the formation of life is a natural consequence of the evolution of matter.
Our understanding of life is, for obvious reasons, limited to our experience here on Earth.  What that experience makes abundantly clear is that at least on this planet, water is absolutely fundamental to life. In our terrestrial experience all life is based on energetic carbon chemistry in water. Where water flows life follows.
It is unclear exactly where life on this planet began. Whether it began in deep sea vents, in the superheated, chemical rich water welling up from near the Earth's molten mantle. Or in coastal shallows heated by the sun. Regardless of where life first arose, it is clear that even in the earliest days, Earth possessed all of the raw materials necessary to facilitate life.

Earth possesses an abundance of Carbon, the fundamental element for all organic chemistry. Carbon's unique bonding capabilities allow it to form long, complex molecules with all kinds of other atoms. With minor amounts of energy, carbon has been shown to easily forms the basic organic buildings blocks necessary to form life, amino acids, lipids, sugars, hydrocarbons. More importantly, due to the unique bonding capabilities of carbon, organic molecules tend to combine and recombine into ever more complex organic structures. And at some point, some 900 million years after its formation, this frothing mass of organic molecules in our great global ocean did something extraordinary, something that would forever alter our planet.

It began to organize. It began to extract energy from its environment and use that energy to replicate itself.

The exact mechanism that caused the first living thing to spring into existence is unknown, it is unclear whether primitive forms of RNA began replicating externally or whether these complex chain of amino acids somehow ended up inside of a lipid bubble and were activated by the presence of electricity or heat or some unknown chemical reaction, but at some point, some humble collection of organic molecules began to do something this planet had never seen before. It began to live.

That first humble organism, was likely an incredibly simple thing, likely capable of nothing more than extracting energy to self-replicate, but it is from these humble origins that everything we are is derived.

Over innumerable generations, these humble organisms replicated. Occasional mutations and variations gave rise to slightly different organisms and slightly different species.

For the first few billion years, these single celled organisms ruled our planet. They were likely confined to the deep oceans, or the shallow coastal seas surrounding the granite continents that were gradually forming due to the Earth's volcanism. At some point, however, yet another in a countless string of mutations gave rise to a multicellular juggernaut and once multicellular organisms began to multiply, evolution was poised to take a massive leap forward. Specialized cells enabled these new creatures to adapt in heretofore unimaginable ways, enabled organisms not only to extract energy from the sun or chemicals, but from other living things, the first predators. Multicellular organisms also have more constituent parts that are each capable of individual mutation, further hastening evolution.

Approximately 1,200,000,000 years ago, the first organisms began to reproduce sexually, purposefully recombining their genetic code in unpredictable ways and rapidly increasing the rate of evolution. Indeed, sexual reproduction is probably the single most significant evolutionary step this planet had witnessed since the rise of multicellular organisms. Asexual reproduction is specifically designed to create a carbon copy of the original and evolutionary advances can occur only through errors or mutations in the copying process itself. Sexual reproduction, on the other hand, creates organisms that are similar, but slightly genetically different from the parent cells.

With the advent of sexual reproduction, the Earth’s creatures grew steadily larger, more advanced, more specialized and more adaptable. Eventually, organisms even began to take tentative steps onto the land. As plants and animals relentlessly fought for greater access to the sun, to prey, to territory, to mates, they became ever more advanced. And once life gained its initial foothold, its march forward was unstoppable.

Throughout its 4.5 billion year life, our Planet has seen four mass extinctions where upwards of 95% of the planet's life was extinguished. Yet each time, after a few million years, life springs back with renewed vigor, marching relentlessly forward with ever more advanced and adaptable species. Finally, after approximately 3.8 billion years of evolution and after four great evolutionary setbacks, one particular species of ape came down out of the trees, taking the first tentative steps down the path of human evolution.

Christians are raised to believe in stories where God created man by breathing life into a pile of dust. Raised to believe that God created the first woman by taking a rib out of that same man and imbuing that bone with life. Does that story make any sense?  Seriously ask yourself if the creation stories made up by ancient farmers and shepherds with absolutely no knowledge of biology, genetics, phsyics or chemistry make any sense in the modern world?  Ask yourself how such a story, written by people with absolutely no actual knowledge can possibly compare to what we can actually see and test with the full arsenal of technological and scientific tools at our disposal.

Even more importantly, how does evolution not make sense? The proof of it is quite literally all around us.

Those who conflate Atheism with nihilism claim that Atheists do not see meaning in life because they reject the idea of God.  This could not be further from my experience.  I see no authorship when I see life. None. And I appreciate life all the more because I do NOT see any kind of authorship behind its existence. The fact that life was not created, that it was not grown in some celestial lab and placed here, the fact that it was not spoken into existence by an invisible space being in no way robs life of its grace and majesty. Life is precious precisely because the odds of its existence are so long. Life is made even more precious by the fact that it is so highly unlikely in any given reaction. The very fact that life exists at all is like winning the lottery five or six times in a row. In no way does that cheapen the power and majesty of existence. It merely reinforces how incredibly precious and indescribably awesome the gift of life really is.

That some require authorship to find meaning in life fills me with sadness because they have completely missed out on what an incredibly mind-blowing miracle life really is. Can they not see the grace and beauty in the fact that the atomic remnants of a long dead star, pulled together by great organizing force of gravity, and gradually organized based on the laws of chemistry formed something truly extraordinary.  That over the course of billions of years these amazing structures replicated and evolved and replicated again to form a planet whose surface is literally alive? That is truly the greatest, most profound, most awesome miracle imaginable.

For countless generations, humans have asked the great question. “How did we get here?” For countless generations, we really had no idea.  We lacked the tools and sophistication and methodologies to even properly approach such a question.  So we made up stories, just like later peoples made up stories about Zeus hurling lightning bolts or how Apollo's Golden Chariot causes the sun to rise each day. We invented stories wherein beings, not unlike ourselves, simply placed life here, in much the same way ancient peoples herded cattle from place to place or raise crops. For countless generations, we invented stories out of whole cloth to explain the great mystery of how our beautiful green and blue world came into being.

What is staggering to me is that now, we really know. We know to within a few microseconds how our Universe came to be. We can quite literally see and know the process of how our Universe evolved. We know how our planet was formed, what is was formed of and how long ago it happened. Even more amazing, we know what happened after its formation, we can see through the genetic record how species split and evolved and split again into a vast, interconnected biosphere. We quite literally know where we came from.

And the reality, the reality of where we came from, of what we are and how we came to be is far greater, grander, more magnificent and profound and meaningful than any story could ever be. We require no authorship to make our lives meaningful. We require no outside intervention to make existence astounding. Our simple existence is the greatest and most profoundly miraculous fact of all. It fills me with a profound sense of joy to know just how cosmically unlikely it is that I exist. It makes me smile simply knowing that the laws of physics and the interaction of time, space and matter can produce something as beautiful and graceful as life. It fills me with a sense of awe and wonder that no Creation myth could ever match. There was a time in my life where I really believed that the parochial God of our solar system created the Heavens and the Earth.

Such a belief seems so small to me now. It cheapens the whole experience of life. Even assuming our local, solar-system God alien indeed created life here, how would that possibly make our existence any more meaningful? How would that imbue life with a majesty it otherwise lacks?  How can such a belief possibly compare to the wondrous reality of our incredibly unlikely existence?
It is astounding that in the United States, the most technologically advanced nation on Earth, nearly half of the population does not believe in evolution. Most have no understanding of the Big Bang, no knowledge whatsoever of stellar nucleosynthesis (the process of how stars create heavier elements out of hydrogen) and no understanding of the mechanics of evolution. They completely fail to grasp the marvel of both cosmic and biological evolution.

This lack of understanding is truly sad because the reality of the processes that gave rise to our existence are so huge and so cosmically monumental that the Atheist cannot help but marvel at the very fact that we are here. In embracing a bronze-age fairy tale, the Religious have missed out on the true miracle of life. They have traded an incredible and profound understanding for a half-baked myth that not only bears no resemblance to the truth, but is also far less meaningful. The reality of our existence is far stranger, more wondrous, and more enlightening than the fiction of creationism. Understanding the size, scope and scale of the Universe, and understanding the way in which it has evolved enables the Atheist to view the world in a way that is impossible otherwise. It grants the Atheist perspective we would otherwise lack.

The most amazing thing, is that for the first time in human history, we are actually within spitting distance of a true understanding of the exact mechanics behind the one of the most ancient questions our minds have ever pondered. We have no more need for stories, no more need for gods or demons or coyotes or spirits. We really, truly know where we came from and the truth is absolutely incredible. That feeling of really knowing where we came from is both liberating and transcendent and it is my most fervent wish to share that knowledge and that feeling of really truly knowing the answer to one of the very first questions of our species with as many people as possible. The truth of where we came from is so much larger than we can comprehend that one cannot help but be humbled and stand in reverence of it.

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