Winter 2005 vol 4.1
Darwin's Dream
Gerald N. Callahan
HAROLD Perry rises from his overstaffed chair. Tired of the commercials and cons of late-night TV, he turns off the set. In the darkened room, the snow in the trees beyond the window glows suddenly bright blue. Harold watches the snow fall for a moment. So delicate, so fragile, so clean. Then he crosses the room, opens the door to the basement steps, and flips on the light at the top of the stairs. He walks sluggishly down into his basement wood shop. The small room, lit only by a slice of light spilling from the stairs, smells of pinesap and freshly cut wood. Sawed-off ends of planks, finishing nails, and steel screws litter the concrete floor. Harold moves as though he is no longer certain of what drew him to this room in the first place. He pulls at the string dangling from the overhead light, a naked pair of fluorescent tubes. The lights flicker then gain strength and hold, bright white, surgical. Harold's blue eyes, set deep below his fifty-year-old forehead, fix on the table saw in the center of the room. He slides his right hand across the ribbed aluminum top of the machine, fingers the carbon-black blade. Then, with the same hand, he reaches beneath the platform and flips the toggle switch there.

The saw responds, shrieks at Harold for waking it. Harold waits as the saw strains to reach full fury. He rolls the plastic knob beneath the table until the teeth of the saw reach well above the metal platform. Then he unbuttons the worn cuffs of his khaki shirt, rolls his sleeves up past his elbows, and brings both arms to rest at the edge of the aluminum platform. All the while, staring fixedly at the blur of the spinning blade.

Harold hesitates then. His eyes nearly close, and for a moment it seems this instant might sew itself shut. But that can't happen, not this time. Harold's eyes open, full-up with calm. Then he moves. In a single motion, Harold pushes both of his wrists, one atop the other, forward, through the saw blade. The saw spews a rip of red straight down his face, across his shirt and over the platform of the saw. Harold steps back, bits of skin and bone stuck to his face and his shirt. He looks stunned. Small red arcs leap from his wrists to the floor.

The saw sings on. Harold looks at the stumps of his arms, then at his severed hands twitching near the blade. He wishes he could stop the awful scream of the saw, but it is beyond his reach now.

He drops his arms to his sides and walks back up stairs, leaving his red

life on the floor as he goes. Harold walks back into his living room. No one is there to greet him. All have gone for the evening. He reaches to turn on the table lamp, then he remembers. Harold drops in the darkness onto the sofa near the window, the sofa with the dark flowered print, the sofa he never wanted. He closes his eyes, and the last of his wishes wash out of him. The sofa darkens beneath him, then Harold dies—alone in the living room, his hands in the basement.

Outside, the snow stops. The cold finally lets loose of the sky. Now there is just the failing and whining wind, a skein of geese, deep orange in the first light of a new day. Now there is just the ragged tooth of reality and the steady song of the saw.

Harold Perry was my uncle, my mother's brother. He and I share genes. He and I share history. Harold's death marked a turning point in my life. I never imagined any one of us was capable of an act like that, cutting himself into pieces on a table saw. I looked down every alleyway I pass now, stare across their weedy expanse, and wonder into what darkness those roads lead.

Harold and what he did forced a bridge across a river I didn't even know existed, opened a door I'm still trying to close. Nothing is the same. Putting Harold to rest, building some sort of back fire around his death, has become an obsession for me.

I'm a biologist. I believe human behavior reflects human history. Most of the things we do, we do because we have to do them to survive. Well, survive and reproduce. That's what the last four billion years has been all about—survival and reproduction. We are all products of those four billion years. And every move we make is governed by that past. Well, up to a point, anyway.

Perhaps it's best to begin at the beginning.

The Big Bang

Actually, this story begins just before the Big Bang. There may be stories that begin even earlier, but I don't know any of those stories. Just before the big bang, every point that is me today overlapped completely with every point that is you today. My father and I were one. My mother and I were one. Orin Hatch and I were one. Harold and I were one. We lay, the bunch of us, far heavier than lead in a single submicroscopic bed. We had no differences of opinion or even of locale. Imagine that, me and Orin. His thoughts mine. My words his. We wished for only a single thing. We saw all things with one eye. We were of one mind, as close as we ever would be. There is no telling how long this lasted, it felt like a long time, though.

One day, all of that changed. With no warning, space-time erupted into itself. Suddenly, there was no one. Just the screaming plasma. None of us

overlapped with any other now, not even with ourselves. We were as free from one another, as free from our selves, as we ever would be. Hurtling toward the edge of infinity, we danced.

Eight billion years slipped by.

Time unimaginable. Then the darkness broke, and flames began to burn here and there in the emptiness. The universe split open—part flame, part void. What happened in the darkness is difficult to say. But inside the flames, things changed. Thermonuclear fusion in the hearts of stars began to slam hydrogen atoms against one another and helium appeared. Then helium was hammered into lithium and beryllium, and on and on. And as the first stars died, the forces within their corpses reached indescribable levels. From those fierce forges came the bigger atoms—oxygen and carbon and potassium and nitrogen, sulfur and calcium filled the heavens—things we would need soon.

A few of us milled around the dying stars, waiting for things to cool a little. As soon as we could, we gathered up the stuff of life in our knapsacks and met in a far corner of the universe. We were a still, dark cloud at the edge of a young galaxy. Uncertain of ourselves, we waited.

Then slowly, and nearly against our wills, I, my mother, my father, my wife, my Uncle Harold Perry, and all who ever have or ever will walk this world, coalesced into a small planet, ninety-three million miles from the nearest star. We were that planet.

It was hot at first. The radioactive elements that that we brought with us were falling apart so fast that even rock could not withstand the heat. The surface of our world was liquid stone. Water was vapor roiling in baleful clouds above a world without a sea, without a mountain, without a blemish.

Below, we boiled. One hundred million years, maybe more, passed and the radioactive elements decayed into stable, cooler isotopes. A thin rock crust formed across the surface of the molten Earth, and through that crust volcanoes pushed up the continents. Solid land appeared.

It grew colder still. And above the rocks and the land, the water vapor began to condense. Then it rained. For a hundred thousand years or more it rained. Rained with a vengeance, as lightning lashed the surface of the planet. Rained without remorse, rained without an instant of forgiveness. Rained as it will never, ever, rain again.

And we washed into the seas.

What happened next, none of us, even at our most wishful, could possibly have asked for. RNA molecules snapped themselves together into long chains. And life, the most remarkable gift of all, began to unwrap itself.

At first, we were molecules. Just genes themselves. RNA. Individual molecules in a sea of discontent. Even when I feel most imaginative, it is hard for me to envision life as a single molecule. But that's how it was for a very long time. My molecule, bumping into your molecule, rising to the surface, sinking to the bottom, lolling on our backs in the sunlight, basking on our bellies in the sand. Molecules. We did what we could.

And mostly that involved reproducing ourselves and eating one another. Sometimes, we even ate our own children. We molecules reproduced ourselves almost at will. We'd just reach out with our little molecular fingers gather up what we needed from the primordial soup—adenine, guanine, cytosine, and uracil—and make more of our selves. We enjoyed life as RNA.

But after a while, the raw stuff we needed to make more RNA copies of ourselves was nearly all used up. First uracil ran short. Then the others followed. Things got harder. Only the fastest RNA molecules were still reproducing, only the fleetest among us. Until one of us found a way to make more food by dismantling other RNA molecules. Then, through our own ingenuity, everything we needed to make more of ourselves was plentiful.

The best eaters and best reproducers made more of themselves quick as fire chews through dry grass. Until, once again, the seas were full of us. And things slowed down for a while. Then, one of us figured out how to wrap herself up inside of oil (lipids, fats) and protect herself from being eaten by other RNA molecules. And the first cell was born. The first person apart from all the others. The first woman with a room of her own, a place to be herself. Suddenly, "me" and "you" had meaning.

Now, all of the rules we would ever need were written: 1) eat, 2) don't get eaten, 3) reproduce. It was never our choice. But it was our chemistry. Time and the sea delivered us up whole, hungry, and lustful.

From that simple chemistry and those few rules would come me, you, my uncle, and all the rest. Only those of us who were good at all three of the rules reproduced. So in a short while, everyone around was good with the rules.

And, as the millennia passed, we got even better at eating, escaping, and making more of ourselves. Better and better. And everything that came our way came to serve those three purposes.

We became bacteria, then cyanobacteria. We took sunlight and used it like a blade to slice carbon from carbon dioxide and release oxygen. Oxygen, the stuff that would one day rot iron and ruin flesh. The oxygen immediately oxidized all the iron in the oceans and then it filled the skies. The brown seas turned azure and the pink skies turned blue.

We ate starlight.

Abruptly, we were everywhere. We fed. We excreted. We anabolized. We catabolized. We moved. We lived. A few of us died. We were jacks of all trades, then. But we were masters of none. There was no place yet, let alone time, for thought, sight, sound, touch, taste, motion, breath, or poetry. But, we had mastered survival. Nothing did or ever would equal us for sheer power in reproduction and survival. We flooded the seas. We fed on one another.

Then communes formed—combinations of bacteria learned to live together for the common good, one inside the other. Eukaryotic life arose, cells with internal membranes. A room for DNA, a place for fire, one place to build things, another to tear them down. Whole genomes were shared and mixed. Some blue-green algae became chloroplasts—the parts of green plants that turn sunlight into molecular energy. Other bacteria became mitochondria—the parts of our cells that burn sugar and make our lives possible. We traded shelter for energy. United, we conquered. Life became symbiotic.

Time unwound itself. We were jellyfish, translucent specters of what was to come. Multicellular animals with the potential of gods. Now there was a path and a place for eyes, and fingers, nerves, toes, livers, lungs, blood, and bone.

We fought with one another almost constantly. We fought for food, we fought for mates, we fought to live. Sometimes we won, sometimes we lost. We lived, we died.

Abruptly, we were fish, vertebrate, cartilaginous, learning new ways to kill. The oceans filled with us. Fish of all kinds—fish with bones, fish with jaws, fish without jaws. Fish lit with lights and fish covered with scales.

And we were salamanders. Spotted, slippery, stub-legged, and thick witted. No longer tied to the sea, we moved onto land, breathed oxygen unmuddied by sea water. We grew lungs. That was novel, at least at first— breathing air, walking around on legs. But after a few million years, it wasn't enough.

We became lizards. Great horned and striped creatures like tetraceratops and dimetrodon, armored with scales and razored with claws. We ate, we rutted, we lolled beneath the ferns while others' bones rotted in our bellies.

Then we took a gamble. One we nearly lost. We became mammals—little shrews, at first. Warm blooded, furred, milky, and misguided. We called ourselves Megazostrodon—large animal tooth. The name made us feel much more important.

Great lizards ruled the world then. Huge carnivores and even larger herbivores careened like broken buses through the valleys and swamps. But we were too small for the behemoths to bother with. We hardly made a toothful for beasts so great. We darted from hole to hole beneath their great claws.

One day, the sea boiled over, and there came a great wind. Water, then fires, raced across nearly all of our world, leveling the forests leaving only ash and stubble. Then darkness, a darkness untouched by sun or starlight.

We huddled in our burrows, eating ice and taking what small heat we could from one another. We never loved the darkness, or one another, for that matter.

Though no one of us knew it then, a meteor, a mere 6.2 miles across, had slammed into the sea near what is now the Yucatan, and the face of the world was changing.

The fire, the darkness, the cold were nearly unbearable. But that fire forged men from mice. In the cold, the great lizards faltered and began to die. But our warm blood carried us into a new age. Now was our time to be something other than shrews and mice, something other than fodder for half the living world. Our gamble had paid off.

We moved into the trees. It was safer there. Fewer things fed upon us in the dark. It was easier to care for our babies. And we became primates— monkeys and apes. Large, strong enough to fight for what was ours. Strong enough to kill. We lifted stones, we gathered together.

We moved back onto the ground and we became men and women. Not Homo sapiens, not yet. But we were homo, Homo habilis, and overhead the African sky glistened with starlight. Now, the only sea we knew, we carried within us. We never spoke. Our thoughts were pictures, pictures of the world—things we might eat, things that might eat us. But the colors of the pictures were changing. We had axes now—sharpened stones heavy as heads. Our jaws grew smaller and our brains grew larger. We worked together and the world spun on its axis. Nothing was beyond us. We had overcome every challenge. We were rich and strong and fecund.

We became Homo sapiens, Neanderthals. Sapient.

We spoke.

Time stretched out even further, and we made music on bone flutes. We carved bits of rock into shapes of women. In Chauvet, by firelight I painted a bear. It was full of me, strong, urgent. You sketched a rhinoceros. I admired it.

We raised goats in Iran and pigs in Thailand. We grew wheat and barley in Iraq. And in Egypt, we counted on our fingers the number of times the sun rose and fell.

We rolled papyrus into sheets and we wrote our names and our words in graceful pictures. Our thoughts fell onto pages and our words found a way beyond us.

We made alphabets in Palestine and Syria. We grew corn in America and smelted iron in Britain. We built the Great Wall.

Rome rose and fell.

Then we nearly died when the plague raged across Europe. Another test, always another test. Once again, all of our efforts nearly came to nothing. We carved the Pieta.

Five hundred years later, our potatoes rotted in muddy fields and in our cellars. We left Ireland then, for another world. New York City chewed us up and spit our remains onto steel rails. We followed the rails to Kansas.

In Kansas, I was born and Harold died. Friends gathered his pieces and carried them to his wife's house where they drank whiskey, smoked cigarettes, and tried to fashion a sense of security from a. shroud.

The Purpose of the Past

All of that, from a simple drive to feed, survive, and make more of us. Thirty thousand or so of the finest genes four billion years and geochemistry could cast. The human genome.

Every one of our direct ancestors survived, at least long enough to reproduce. Every worm, every jelly fish, every lizard survived. We know that simply because we are standing here. Someday reproductive technology may reach beyond this. But for now, our existence is proof of our ancestors' skills. And that is their gift to us, survival wrapped up inside of twenty-three pairs of chromosomes.

For millennia, evolution has been shaping human genes for a single purpose—reproduction. Eating and not getting eaten actually only serve the purposes of delivering us to the times and places where we will have opportunities to reproduce. Vision, to find mates, hearing to find mates, brains to find mates, and fingers to hold them.

Those who didn't measure up didn't reproduce. Evolution is a harsh mistress. Genes that helped people make more of themselves survived. Genes that didn't help quickly sunk to the bottom of the gene pool and were eaten by scavengers. Survival of the fittest. Over the years we grew smarter. We grew stronger. We grew warier.

At the moment of conception each of us is given that legacy—a bag full of genes old as life itself. Genes that brought fish from the dark into the light, genes that made lizards strong, genes that allowed apes to stand up, genes that crushed others and forged a living from their remains, genes that stacked rock upon rock and saved us from the cold, genes that make us tall or short, blond or brunette, blue-eyed or brown, genes that write poetry or create constellations, genes that stared at the tars and wondered, and genes to make us care about all of it. A genome full of genes. Genes that will save us.

Up to a point.

The Death of Charles Darwin

And that point is at about age fifty for men and somewhat younger for women. Once we will bear or father no more children, our genes are ours to keep.

We will pass them on to no one. Now, we are on our own. No gene that saves us, no gene that kills us, will ever change another's life. Now there is only unnatural selection.

Abandoned by Darwin, we live in a true terra incognito. A place our genes know nothing of, a realm completely unexplored by and of no interest to evolution. In that place, we are at the mercy of biology freed from its own history, biology with no fear of the future, biology in its rawest form.

A place few of our ancestors ever found themselves.

The Power of Myth

Jean Baptiste Pierre Antoine de Monet, Chevalier de Lamarck was born on August 1, 1744, in Bazentin-le-Petit, France. He was the last of eleven children. Perhaps his struggle to find a place so late in a family so large fired his interest in evolution. Regardless, after a period in a Jesuit seminary, a stint in the military, and a brief career as a bank clerk, Lamarck fell in love with botany and medicine and the diversity of living things.

Around 1801 he began to publish the ideas that would make him so famous or, more accurately, infamous. Larmarck had seen the ways that animals and plants changed with time. He was convinced of the reality of evolution. And, rather ingeniously, he proposed that the stressors of everyday life drove evolution. Change, he argued, occurred when an animal or a plant was forced to struggle for survival, to reach beyond its comfort level in order to live and reproduce. Then, somehow the changes that came from the struggle to survive were passed on to sons and daughters, or calves, or foals, or kittens—evolution through inheritance of acquired characteristics.

The classic example was the giraffe. Giraffes, Lamarck proposed, had long necks because their ancestors had to stretch their necks very hard to reach the higher leaves on trees—the only leaves that remained after all the other giraffes had fed. The stretching made the giraffes necks grow longer and the long-necked giraffes then passed that trait on to their progeny.

Today Lamarck's work is most often presented as sheer foolishness, as an example of how wrong someone can be about how evolution works. The bumps, bruises, and stretches of a lifetime do not change genes, particularly the genes present in sperm and egg—the only genes of ours that ever reach our children. Giraffes' necks didn't get longer because they were stretching them all the time. Giraffes' necks got longer because one day, on some long-forgotten veldt in central Africa, a mutant giraffe was born. This giraffe's neck was much longer that his brother's or sister's or mother's or father's. This giraffe thrived because he had all the food he could possibly eat—the high leaves that none of the other giraffes could reach. So the mutant giraffe reproduced early and often. And all of his sons and daughters had long

necks. And they reproduced early and often. And so on, until all giraffes had long necks.

Lamarck had good intentions. He just wasn't as smart as Charles Darwin. Lamarck, though he tried, was just wrong. That's what our textbooks and our teachers tell us. And maybe Lamarck's genius wasn't meant for the Galapagos finches. But that doesn't mean he wasn't a genius.

At the moment of conception, our parents give to us their bag of genes. As Darwin imagined, those bits of DNA probably don't change much in a single lifetime, not by stretching, not by running, not by wishing.

Later, though, at birth, and even before, each of us is given another treasure—a tome full of ancient tales. As soon as we have ears, they are filled with our parents' stories. We get them first in lullabies and books read aloud. We get them from the radio and the television, the toys that fill our cribs, and the mobiles that twirl over our heads, the words our parents share with us and the words they share with one another. And as we grow so do our stories.

And like our parents' genes, these stories change us, literally, physically change us. As we listen to the words, our brains change shape and size. Then the wires that stitch together our neurons untie old knots and forge new ones. Children read aloud to, even while they are still in the womb, quickly learn to love the stories they have heard and to shun others. And infants and children who never hear words and stories lose the ability to ever understand them.

Words change our brains, forever.

Just like genes, stories change the course of our lives. Unlike genes, stories are told and retold, shaped and reshaped throughout our parents' lives. By the time the stories are handed over to us, most of them are no longer the stories our grandparents gave to our parents. By the time we inherit them, like Lamarck's giraffes, the stories have acquired the characteristics of a lifetime—including all the bumps and bruises, wishes and stretches. Later, we acquire more—our grandparents' original stories, the stories of our culture, the stories written in our books, the stories of our people. The human bibliome.

Lamarck may have been wrong about genes, but he was right about stories. Living changes our stories, makes them more intricate, more personal, better, perhaps. And then we pass those stories to our children and our grandchildren. Long after we are capable of producing a child, we are fully capable of weaving a tale. And we are capable, as well, of passing stories on to our children and our grandchildren and anyone else willing to listen. After reproduction, we may be abandoned by Darwin. But Lamarck quickly reaches out for our aging hands.

After the age of reproduction comes the age of story, a time for telling and retelling the tales that have driven our lives. How to catch fish. How to make love. Where the Earth came from. Where it is headed. Why birds fly and worms crawl. How to make a flute. How to build a home. How to hear mountains speak. Why we cry.

It is the time for words.

Compared to genes, words are very young. But that really makes no difference. Though they came late, words changed everything. Words erased solitude. Words carried us beyond genes. Words pulled us from the trees and pushed us toward the stars. Words drew us closer. Words created gods and destroyed demons. Words made us immortal.

Our genomes made us breathe, our bibiliomes made us ask why.

Even in Darwin's most lucid dreams, he never imagined the power of story or the force of words.


So, what about my Uncle Harold?

All the times I've sorted through our past together, I haven't found so much as a kernel of forewarning. No shadow of the specter of what was to come. It must have been something else. There must be a piece that I am missing, a part of the story I don't know. Something about Harold my parents intentionally never told me. There must be

In 1964, identical twin brothers walked into the medical offices of Drs. Michael Lesch, and William Nyhan. The two boys appeared physically normal, except. . . each had chewed off most of several fingers, chewed some fingers beyond the second knuckle. And each boy had gnawed off parts of his lips. Both boys' heads were bruised all over and their mother was nearly out of her mind.

The two physicians had no idea what might cause such horrible and destructive behavior in the boys. But because the diseases seemed identical in both of the twins, Drs. Lesch and Nyhan immediately guessed the underlying problem was a genetic disorder. Later research would bear them out.

The twins' disease, now called Lesch-Nyhan disease, is caused by a mutation in a single gene. The gene, hgprt, encodes an enzyme. This enzyme helps to regulate recycling of chemicals to make nucleic acids, the stuff of genes. Nothing, though, that you'd ever expect could make someone to chew their fingers off. But approximately one in every one hundred thousand children born develop Lesch-Nyhan syndrome. And these children do self mutilate, chewing off fingers and lips and banging their heads until they're bloody and unconscious or stopped. One gene does that. Just as there are bad stories we humans have never been able to purge ourselves of, there are still evil genes.

But I don't know of any mutations among Harold's genes. Maybe I wouldn't though. Maybe no one would. Or perhaps those who knew chose never to tell. But I don't think that's it. Most genetic mutations take their toll early in life. Far as I know, Harold's life to that point had been pretty normal. Like all of us I'm certain, Harold woke one day to the reality of abandonment. Sat up in his bed and looked at the loose skin across the backs of hands and knew that Darwin had checked out. And I'm sure, in that moment, he realized, at some level, that his genes no longer gave one good goddamn whether he survived another day.

But I doubt that that happened the day Harold died. And whether it did or not, such a discovery by itself—the simple realization that evolution, or youth, or whatever you want to call it has up and left—doesn't lead most of us to the table saw in the basement.

So how do I absorb what happened? How do I build that back fire?

Every part of my life I have packaged inside of stories. Where I came from, where I'm going to, why I bother. Life. Harold doesn't fit into any of those packages. Harold doesn't even fit into the stories I tell about genes— stories I've worked on for more than thirty years.

But everything has to do with stories. And once our genes have walked off and left us, the only thing that stands between any one of us and that table saw is stories. People live inside of stories. We have to know how to catch fish, how to make a flute, how to hear mountains speak. We have to know why we cry.

Harold was a handsome man, brown as a berry and quick to laugh. I loved him. I loved spending time in his house, roasting burgers on his barbecue, exploding fireworks in his backyard, and sitting next to him as the black storms of Kansas rode across his fields, his arm around my shoulders. He made me feel safe, even when lightning flared and thunder barked, even as the hail stones pelted us. I don't remember that we talked very much. Perhaps, I have just forgotten. Though it seems I would remember things like that.

There's something I'm missing here. Something important.