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The Disposable Male
Sex, Love and Money: Your World Through Darwin's Eyes
By Michael Gilbert
The Hunter PressCopyright © 2008 Michael Gilbert
All rights reserved.
Eternal Forces Shape All Living Things
When ancient mapmakers puzzled over what lay beyond their uncharted world, they inscribed the words: "Here There Be Dragons." The omnipotent force behind the Big Bang, the cosmic explosion that gave birth to the universe remains anyone's guess. Every civilization has fashioned its own creation story to unravel this most basic mystery, addressing a universal desire to make sense of the world and our place in it. If we were to sift through these epic tales, surveying cultures far and wide, we might not stumble upon dragons, but we would surely discover a vast pantheon of gods and goddesses.
In search of a suitably impressive origin for the Big Bang, our attentions might well focus upon the majestic Greek god Zeus, known to the Romans as Jupiter. Though he displayed awesome power and commanded breathtaking authority, Zeus revealed a fondness (some called it a weakness) for mortal women. Supposedly, he often descended to our realm to pursue earthly pleasures with those who attracted his attention. Back atop Mount Olympus he was fond of hurling thunderbolts when angry, yet another of his human quirks. The colossal lightning dagger he thrust into space almost fourteen billion years ago to get things started must have been impressive indeed because the explosion is not over. The universe continues to expand.
The Big Bang was an eruption of unimaginable force, a thundering exclamation of raw, brute energy. Launching the elements of creation in every direction from a single point of origin, the convulsive spasms at the dawn of the universe sent flashes of radiant light against the dark emptiness. It was hot — ten billion degrees hot. Fashioning time and space into a four-dimensional matrix, this cosmic tremor is the source of all the energy and matter in our universe.
From the thrust of the first explosive discharge sprang many more reverberations as billowing black clouds of fragmented matter and gossamer webs of embryonic galaxies gave shape to the universe. Across billions of light years, the embers we know as stars streamed outward, vibrant sparks from the convulsions at the genesis of space and time. As the seminal Big Bang explosion flamed out, it produced a hiss like a whispering seashell, an echo of creation scientists can still hear.
Among the 100 billion galaxies that formed in our universe was an auspicious constellation called the Milky Way. At the farther reaches of this spiraling web, among billions of other stars, a solar system emerged with nine big planets orbiting around a confident sun. And there, the third rock from the center, was a pristine blue and white jewel calmly spinning against a sea of dark space.
Our planet took shape about 4.5 billion years ago as its heavier elements gravitated to the core and the lighter ones floated toward the crust. Ignited by immense lightning flashes, crashing thunderclaps, and volcanic eruptions, wild climatic tempests charged the earth's atmosphere into a cauldron of creation and destruction. During these lush incubational epochs, as our planet simmered under a radiant sun, a potent stream of asteroids hurtled through the cosmos like galactic spears, penetrating the earth's atmosphere, seeding the globe with the building blocks of life.
Within a pregnant, primordial sea nearly seven hundred million years later a miracle occurred. As the earth's surface cooled and began to take shape, chemistry transformed heat and light into biology. Life appeared as microscopic, single-cell membranes. Clinging perilously to existence, as tenuous as soap bubbles, living organisms took hold. From these puny beginnings, a mighty procession was set in motion.
Over the eons that followed, the polarities of fire and ice, light and shadow, volatility and serenity would envelop the planet and forge our natural world. Just where this uncharted adventure would lead no one could predict. But one thing was certain. There would be dragons aplenty along the way.
The Job Is to Survive
First and foremost, there is nature. It is everywhere and in everything, commanding the majestic heights and squalid depths, governing our universe with an all-encompassing and absolute force. For the longest time, when our ancestors hugged fearfully to its bosom, they engaged the natural world in mystery and awe. They took what they needed and lived by nature's commands. But the human odyssey has come a long way from the forests and savannas. These days, diverted by the distractions of modern life, nature rarely summons our immediate attention.
Until we are reminded who's boss. Shattering earthquakes, sweeping tsunamis, and violent hurricanes topple our feeble structures and drown our cities; famine claims whole tribes; killer flu pandemics and plagues rise up to smite king and peasant alike. During these tempests and trials, the Earth shudders and great cities are buried. Nature dissolves our brazen sandcastles in fits of regal temper. We are put in our place. Beautiful beyond measure, destructive beyond our capacity to resist, sweeping all before it, nature answers to no one. Nature is imperial.
As much havoc as it creates, nature propels life with even greater power. The deep will to survive is the underlying theme of all life. Plants cling to existence against the harshest conditions; animals struggle to survive in the face of crippling ailments; humans mount heroic battles to endure against tremendous odds. The will to survive is a dazzling testimony to the power of the primal command: life of almost any kind is better than no life at all.
Survival is our first and most powerful instinct. It is deeply encoded in our genetic and biological core, compelling us even without thinking, making us self-centered, calculating, and determined to persist. But sooner or later, all living creatures expire. Yielding to age they perish. To "survive" beyond our own lifetime, we must regenerate ourselves and reproduce. You are able to read these words because every one of your ancestors survived long enough to do just that — reproduce — if nothing else.
Sex is the engine of evolution. Appropriately enough, it has a torrid history. The saga begins a long time ago when the tumultuous forces shaping our Earth propelled the first gene-carrying packages into existence.
The Primordial Soup
Long after the Big Bang, when things eventually settled down on planet Earth, water — the elixir of life — seeped into the atmosphere along with hydrogen and nitrogen. Baked, boiled, radiated, and electrified by staggering bolts of lightning, these elements brewed a cauldron of filmy air in a solar inferno. In due course, the molecular building blocks of more complex life took hold.
As miraculous and baffling as this spontaneous event may seem, scientists can readily recreate this moment in their labs. Shooting sparks of electricity through a beaker containing the earth's original elementary gases produces the same chemical foundations of planetary life. Getting hot and bothered has been the driving force of creation ever since.
Bacteria were among the first forms of life. Though we are inclined to think of them as nasty little things without redeeming value, their ability to act as the foundation of more complex organisms has transformed the Earth from a barren and hostile globe to a vibrant and glorious domain. Modern life forms like us still can't survive without them.
The original kinds of bacteria were tiny, single-cell organisms. Battered by the ferocious elements, they cooked under a searing sun and were bombarded by intense radiation. Resilient little critters, they persevered, unicellular dots hanging on for dear life. That's all there was on Earth for two billion years.
Eventually, the single-cell molecules cavorting in the primal broth somehow arranged themselves in sequences. These networks of molecules then achieved a simple but quite miraculous capacity: they began to reproduce. They copied themselves and split in two. In the hop, skip, and jump of another billion years, these microscopic bits also managed to encase themselves in an outer "skin." Evolving cells, sealed in delicate membranes that separated them from their soupy environment, achieved a separate identity.
In time, these simple cells developed elementary methods of connecting with each other. They swapped notes, blending and becoming absorbed into one another mostly through bizarre acts of genetic fusion and cannibalism. Relinquishing their cellular independence, two distinct genetic parcels would occasionally merge and become one. This wasn't quite sex as we've come to know it, but you need to start somewhere.
Strength, it turns out, was achieved in unity. The little bags of merged bacterial cells began to expand and diversify internally. Less vulnerable than simple, single-cell entities to radiation and other climactic enemies, these tiny bacterial alliances kept getting better at surviving in the primordial soup. Mixing and matching their fortified genetic elements for eons, they built up reservoirs of biochemical information and triumphed over weaker organisms.
Like a division of soldiers fighting for a common cause, these increasingly complex, multicellular organisms also profited from internal specialization. Some cells, or parts of the organism, could focus on propulsion, some processed and discarded nutrients, while still others concentrated on defense. Better able to protect themselves, these more elaborate entities hung around longer and replicated more, transferring their expanding code of life from one generation to the next. From these humble beginnings, complicated things like plants and animals would soon become possible. (Well, relatively soon.)
We are used to thinking about time in the context of our own lives. Seventy or eighty years seem an eternity when that's how long we live. Usually, we organize our lives in months, weeks, and days — sometimes in minutes or seconds. To get a sense of evolutionary spans, however, we need to stretch our sense of time.
Imagine, for example, that we are measuring the epochs since the Earth first formed all the way to the present-day on a twelve-hour clock — at noon the Earth is newly born; midnight represents today. Life first appeared on Earth at about 2:30 P.M., or 3.5 billion years ago. A sense of perspective is suggested by the fact that the first dinosaurs showed up at thirty-five minutes before midnight. Our first hominid ancestors put in an appearance just thirty-nine seconds ago.
Errors and Omissions
In the same way that computers duplicate a digital file, when genes copy themselves to the next generation, they do it with astonishing accuracy. Errors are rare, less frequent than a single typo in the duplication of this book. But mistakes happen. The reproduced gene has too much or too little of something, or the order is messed up. These mistakes are called mutations.
Mutations have neither design nor intention. They're just mistakes. Most of the time, they are as insignificant as a typo. Usually, mutations get buried when the organism in which they appear dies, or they get passed along to the next generation as weightless baggage. Sometimes the mistake is so damaging it causes the creature or its offspring to die before the error can be passed on.
The important point about mutations, however, is that there are opportunities in a mistake, sometimes big ones, because these random genetic aberrations may cause a useful new trait to emerge. They open the door to innovation. The critical thing about a mutation is whether or not it conveys some kind of benefit to the organism. If it does, the plot, as they say, thickens.
A beneficial mutation may improve an animal's prospects of survival, which means being around long enough to procreate more often. Eventually, greater numbers of the evolved model are in circulation as larger proportions of the species carry the mutated gene. Over time — usually a very long time — the mutations build on one another and start to accumulate.
Imagine you are a largish creature hanging around a few million years ago, a cross between a horse and a giraffe. Your ancestors have been happily grazing in a field of grass, shrubs, and trees for generations, but lately the pastures have been tapped out and you're getting hungry. In search of food, you decide to head south, while others of your group head north, and still others stay put to tough it out. It so happens that the foliage down south is more abundant in tall plants and trees. A long neck would come in handy and any of your descendents with this mutation will win the lottery. To make a long story short, the extra neck length will allow them to feed higher on the trees; the mutation is helping, making things more efficient and life easier. Their progeny live longer and mate more often.
Like the compound interest that rockets your credit card balance skyward, useful mutations build on one another. Time-lapse photography would reveal a neck gradually getting longer, perhaps jumping ahead once in awhile. This process of accumulating mutations continues until longer necks are no longer an advantage. Descendents get so stretched out they can't hold up their heads, or they become vulnerable to attack. Or the foliage doesn't grow that high. At which point longer-neck mutations are no longer a benefit and may become a burden.
In the meantime, in the other direction, up north, where there were no trees or tall growth, shorter-neck genes worked best. Descendents of the common ancestor who picked up shorter-neck genes prospered and multiplied there. Across thousands of generations, necks got shorter and thicker, and their owners became good at eating things closer to the ground.
Over a near eternity, the original animal, the one that did not head off in either direction, may have survived in the played-out fields because so many others left; or it may have disappeared altogether. Down south giraffes evolved; up north, horses. Even if their common ancestor survived, neither the giraffe nor the horse could breed with it, or with each other. Evolved from a common, probably extinct ancestor, two distinct new species grace the world.
Nature Loves a Winner
These elementary workings of adaptation and natural selection are the forces that have shaped our bodies and our minds over a near eternity. Animals may look like they are brilliantly designed for their place in nature, but that is because, over time, they have been designed by nature. Advantageous mutations help plants or animals adapt more efficiently to their surroundings, promoting survival and greater reproductive success. Eventually the new and improved attribute becomes a standard feature. Of course, new species are not necessarily better ones. A horse is no better than a giraffe. Close to the ground, horses make a living on grass, while giraffes subsist on trees. We know that they are successful because they are both still around.
While many of us grasp the general concept of evolution, even the idea of a gradual lengthening of necks, the development of complex body organs is more difficult to comprehend. Consider the eye, the source of most of our sensory data. Surely this elaborate instrument did not just pop into existence one day. Hey, look everybody, I can see! Like all the complicated parts of highly evolved creatures, vision started out as a simple organ and evolved in increments. Perhaps a long-distant ancestor developed a flimsy membrane on its face, photosensitive spots thin enough for light to penetrate, allowing the creature to sense a change in its environment.
Let's say this creature is a lowly cockroach scurrying across your kitchen floor. This cunning, adaptable insect — which appeared before we did and will almost certainly succeed us — jerks to attention as you switch on the light and briefly freezes in expectation. When the light comes on, it senses a change, and its cautionary instincts tell it to scurry under something. The simple capacity to detect a difference in its environment has conferred a powerful benefit. The beetle without this mutation, caught in the open, meets an untimely death. Beneath the dishwasher, the slightly more evolved roach survives to propagate and pass on the thin membrane gene, the one that says "something's not right" when the lighting changes.
From such modest beginnings, over a maddeningly long period of time, are such heroic organs as eyes developed. Many subsequent random mutations in the new and improved line of cockroach may lead nowhere but, given enough time, the mutations will accumulate, the sensitive membrane getting thinner, drawing in more light. Eventually, as the species evolves, a simple skin depression may appear, tiny receptor cells emerge as the sockets form into spherical enclosures suggesting the direction of light and shadow. In time, a jelly-like surface, a crude lens, and optic nerve structure develop.
Many blind alleys ensue, so to speak, but over millions of years, in tiny shadings with the occasional lurch, something that looks a lot like an eye can materialize. In addition to sensing when the light changes, the evolving cockroach begins to make out shapes such as a smorgasbord of crumbs on the floor or your house cat bent on torture. Improbable as it may seem, eyes have evolved, over a near-endless span of time, separately within many different animal lineages and can be seen today, in the various intermediate stages, in animals everywhere in nature.
In the same way, explanations can be provided for all the many complicated aspects of nature — from intricate internal body organs to the development of mechanically sophisticated features such as a primate's elbow, an elephant's snout, a bird's wings, or a dolphin's rudders. From an insect's eye to the thorns that protect a rose, nature selects mutations that help an organism better adapt to its environment, survive, and propagate.
Scientists have documented this process using fossil records, the skeletal blueprints of our evolution etched in stone. Despite some gaps, the fossils display gradual alterations that, strung together like frames of a movie, tell the story of natural selection. Researchers can also recreate these basic evolutionary mechanics in their labs and on their computers, using microscopic organisms that reproduce faster than a kiss. In a matter of days, they evolve and become different creatures.
Excerpted from The Disposable Male by Michael Gilbert. Copyright © 2008 Michael Gilbert. Excerpted by permission of The Hunter Press.
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