Notes on a Tomato Plant

There is a tomato plant growing from a pavement seam, next to Track No. 4 of the Bay Area Rapid Transit (BART) system's MacArthur station. I noticed it a few weeks ago and now I am altogether fixated on its plight. Every day I check to see: Is it still there? Or did some brutish maintenance worker squirt it with Roundup? What's the tomato count? Have any more of them ripened?

BART is the San Francisco Bay Area's main commuter rail system and the MacArthur station is one of its busiest. At the height of rush hour, hundreds of passengers race pell-mell up and down the station stairs, indiscriminately bashing each other with their messenger bags and wheeled brief cases; ten-car trains rumble through at three-minute intervals on four different tracks. The station stands adjacent to The Maze, the Bay Area's busiest freeway interchange, with six lanes of heavy traffic pounding past on both sides.

And in the middle of this bedlam, inches from the rampaging flow of Richmond-to-San Francisco trains, stands that silly tomato plant. Quiet as you please. Soaking up the sun as if it was rooted in some old lady's window box; just going about its own business, photosynthesizing and producing round globes of succulent fruit without help from anyone. I find that amazing.

This week it was sporting about three bright red tomatoes, with another four or so green ones waiting on the sidelines. Nobody molests it. The fruit, unreachable from the platform, remains unplundered. Before long, the tomatoes will ripen, then fall to the concrete, rot and desiccate; the plant's leaves and stem will brown and shrivel; the loosed, dry seeds will blow about in Autumn's cool breezes and some will find their way into other pavement seams on the station platform. Next year those crevices might issue forth still more tomato plants. And so the cycle will continue, just as nature intended. In a decade, MacArthur station may be nothing but one huge tomato patch.

OK, not really, but that little plant, along with every blade of grass or a bloom of dandelion I see valiantly thrusting itself through a sidewalk crack, reminds me of nature's awesome resilience and dogged persistence.  Despite our best efforts to screw things up, Earth will prevail. As much as we humans contrive, construct, convolute, control and commit all sorts of nastiness on this precious little blue marble we inhabit, when we are gone, the planet will take itself back and miss us not even fractionally. It will wait, patiently and quietly, while we asphyxiate and poison ourselves into oblivion, and then it will repopulate itself with some other species and forget all about us.

The issues we currently face surrounding environmental degradation -- global warming, pollution, overpopulation, depletion of natural resources, destruction of ecosystems -- do not threaten our planet. They threaten us: you, me, our kids, the heavy guy next to me on the BART train who's hogging more than his fair share of the seat, his kids... We're not destroying the planet, we're just making it completely unlivable for our kind. I suspect that, after the human race has returned to dust, whatever is left of Earth's organisms will, like weary party hosts, heave a sign of relief and say, "Thank goodness that's over. I thought they would never leave!"

Prevailing paleontological theory maintains that there have been five mass extinctions in Earth's history. None killed fewer than 50% of the planet's organisms. The worst obliterated 90% of all Earth's species. And (surprise, surprise) all five occurred due to climate change. The first of these events -- the Ordovician-Silurian extinction, 439 million years ago -- happened when glaciers froze over the planet's surface causing obvious logistical problems for the predominantly marine-based life forms of the time. Somewhere between 50% and 60% of marine genera died off.

The next extinction -- a bit of a mystery -- ended the Devonian period (364 million years ago) and hosted the swan song of 57% of earth's marine genera. That extinction was probably also tied to global cooling, though paleontologists are still arguing over the ultimate cause. They throw around terms like, "stable isotopic excursions," "tektites," "platinum-iridium anomalies," and "physico-chemical events." It's not pretty. Don't watch unless you've got a strong stomach.

The Permian-Triassic extinction (251 million years ago), which has also been called "The Great Dying" or "The Mother of All Extinctions," relegated 90% of marine species and 70% of terrestrial vertebrates to the fossil realm. Some believe that Earth's biodiversity has never since recovered to match that of the Permian period. The Permian-Triassic extinction, and the one that followed at the end of the Triassic period (about 200 million years ago) -- which, in case you're keeping score, spelled quits-ville for 52% of marine genera -- are thought to have been caused by global cooling resulting from a double-whammy of asteroid impacts (talk about your Spare the Air days) and massive volcanic eruptions that generated noxious gases surpassing all current-day SUV exhaust emissions and cow farts combined.

The last of the five major speciation do-overs happened a mere 65 million years ago (yesterday, by galactic standards), at the end of the Cretaceous period. Again, asteroids and volcanoes were to blame -- a plummeting hunk of space trash gave us Yucatan's Chicxulub Crater and a massive lava flow in India created the Deccan Traps. Nearly half of the earth's marine genera, along with 18% of its land vertebrate families, including Dino & Co., paid their bills and checked out -- permanently. It was only then that, hidden somewhere in the duff of a gymnosperm forest, a small band of tree shrews began launching their take-over plans. And, through a miraculous series of evolutionary accidents, not to mention utter dumb luck, here we are -- running the planet, or so we think.

Modern humans have existed for only the smallest fraction of Earth's history. And for only a still smaller fraction of that time have we had means to exert measurable control over our environment. We are specks in time; we are a cosmic triviality. We are weak, soft-bodied, dull-toothed, clawless, naked apes who would long ago have become hiena-chow, were it not for an overly-developed, highly-specialized bundle of neurons floating delicately inside the bony sphere we carry atop our shoulders. That neuronal mass has endowed us with an astounding intelligence, but also and quite unfortunately, an obnoxious arrogance, which I fear will be our undoing. But, I believe there is hope -- if only we can learn to truly treasure our world.

If you can manage it some day soon, I challenge you to pry yourself away from your T.V. and march your lazy butt a couple of days into the nearest wilderness area, where I guarantee you will become swiftly and wondrously reacquainted with the quality of your own insignificance. You will suddenly feel very small and vulnerable and you will, hopefully, realize what a very big place the world is, how it's not always particularly friendly, how it really doesn't care whether you live or die, and how it is certainly deserves more respect than you are currently affording it. Moreover, you will hopefully come to recognize just how tenuous, and at the same time tenacious, life is.

The global events that led to Earth's previous mass extinctions were huge -- far beyond any cataclysm humankind has yet witnessed and possibly far beyond any cataclysm humankind could generate. Nobody knows for sure whether the current atrocities we perpetrate on this planet are significant enough to precipitate our own extinction. This tiny globe we live on, in a distant corner of an obscure galaxy, in an incomprehensibly vast universe -- this planet is a moody thing. In its 4.6-billion-year history, Earth has been variously gaseous, molten, soggy, parched, sweltering, frigidly, noxious, desolate, teeming and violent. For the blip of time we have lived here, Earth has been a relative paradise. Anomalously so.

Perhaps the global warming we are currently observing has nothing to do with our dependence on petroleum-powered machines or our destruction of rain-forest acreage by the millions. Perhaps the polar ice-caps would be melting anyway, because, like the life-cycle of that tomato plant on the BART tracks, it is just nature's way. Perhaps there's nothing we can do about it. Or perhaps there is. Humans are a part of nature and ourselves possess the same awesome resilience and dogged persistence as the MacArthur tomato plant. If only -- as they say in the comic books -- we would use our powers for good instead of evil. However you look at it, I don't think it would hinder the cause if we paid some respect to our wondrously beautiful home -- while we're still here to appreciate it.