Lifting Seas to the Skies – The Invention of the Tree
It’s 100 million years ago. You, a pioneering land plant that invented leaves, have a problem. Insects have been plundering your precious sexual seed, your pollen. So you’ve done a judo switcheroo and have convinced these insects to be your sexual carriers, air-lifting your male pollen to other plants’ female parts. You’ve invented inter-species commerce. And you’ve done it for one single reason and one reason only: sex.
Now what if you, the plant, could convince the insect to do your bidding even more effectively? What if you could control the insect? That sounds impossible. And way beyond the principle of least action. How in the world would you, a green creature rooted to the land, “talk” to an animal that walks, flits, and flies? Much less give it commands. Ridiculous.
But, still…what if you, the plant, could interrupt the insects’ random bumbling and get it to come over here just when you needed it most? What if you could get it to land on you at the very moment when you are bursting with pollen, pollen that needs a ride? Even better, what if you, the plant, could convince the insect to cover its fuzzy body with your pollen? What if you could convince it to maximize its pollen-carrying capacity by loading pollen onto the hairs of its head, its chest, its abdomen, and its legs?
Then what if you could convince the insect to go directly to another plant of your species, one that was sexually ripe, one whose eggs were aching for a mate? Better yet, what if you, the plant, could convince the insect to go directly to another plant’s female sexual parts? Yes, what if you could persuade the insect carrying your pollen to go direct to another plant’s oogonium? To the plant’s egg-fortress. To the highest point of that fortress, to its tall, slender tower? A tower tipped with a drop of sexual fluid
What an incredible extension of your power that would be. What a precision transportation service it would add to your sexual toolkit. But what an outlandish fantasy. Especially coming from you, an organism that has no ability to fantasize. And what an act of hubris. What a blow against nature’s existing “harmony,” her well-measured status quo.
What an act of defiance against the continual collapse into chaos demanded by entropy.
But is it even possible? How in the world would you, a plant, pull something like this off? How would you kidnap, seduce, and recruit a radically different kind of living thing? The answer? Materialism, consumerism, waste and something more. Persuasion, suggestion, and bargaining. Or, to put it differently, advertising. “Meaningless” bling. The sin of vain display.
But working this out would not be easy. Not at all. Remember, you plants invented pollen 300 million years ago. Insects gorged on the stuff, plundering it, stealing it and diverting its for its purpose, forcing you to waste vast amounts of excess resources. Then, wham, you green things did it. You turned your plunderers into precision transporters. How?
You came up with your great persuader. You came up with an innovation so new that it was startling—an interspecies communicator, a cluster of semaphore flags that insects could understand, a fistful of temptations insects could not resist. You came up with a form of consumerist, materialist display so far beyond the bounds of the law of least effort that it defies belief. You came up with your killer app. You came up with the flower. And with the flower, you hit a motherlode. You hit an evolutionary vein. And you invented the “sin” of vain display.
When flowering plants popped up in in the fossil record roughly 120 million years ago, they spread at astonishing speed. 400,000 kinds of angiosperms emerged from the womb of impossibility, 400,000 species of flowering plants. Those species would eventually include everything from peas to oak trees and from riceand wheat to corn. And someday in the distant future rice, corn, and wheat would take the principle of tempting radically different creatures into multi-species partnerships far beyond the first flowers’ recruitment of mere insects. Rice, corn, and wheat would recruit humans like you and me. They would recruit entire human societies. Plants would invent farming. But that would be 135 million years down the line.
Where did flowers come from? How did you plants invent them? Four hundred million years ago, you plants were a sorry mess. Yes, you’d defied nature. You’d rebelled magnificently. You’d dared to leave the sea, taking a chance on carrying your own internal water supply, a bit of the nurturing sea, within you.
But, in the words of New York Times science reporter Carl Zimmer, you “were little more than mosses and liverworts growing on damp ground.” You were a roughly two-inch high coating of green spread in spotty patches across the landscape. Then, 350 million years ago, 150 million years after you’d left the waters, you came up with a radical invention—the leaf. The leaf was a technological triumph, a sheet of gadgetry beyond belief.
It was a flat panel of tissue with specialized ventilation holes—stomata–to let carbon dioxide in but to prevent too much water from going out.
It was a solar energy panel—a panel riddled with the tiny, round, green engines of photosynthesis—chloroplasts—green disks only three times the size of a bacterium. Those tiny green polka dots pulled off one of the most astonishing technological tricks in the history of the cosmos—they grabbed the machine gun bullets of photons, turned them into a power source, then sucked in molecules of carbon dioxide gas from the atmosphere and used the photons and the gas in an industrial process that built carbohydrates and sugars.
The leaf broke the rules of nature, gave a finger to the existing order, and made the law of least effort look silly. Among other things, it had sophisticated plumbing. It had veins to keep it supplied with water pumped from a root system beneath the ground. Which meant that it defied one of nature’s most basic laws: gravity. If lifted water high above where water naturally “wants” to go. But pumping water on high was not the leaf’s only anti-gravitational trick. The leaf’s internal engineering allowed it to be cantilevered above the old-fashioned, ground hugging moss and liverworts.
Then you leafy plants went a giant step farther. You mounted nature’s second great space program. You invented new building materials: lignin and cellulose. Using these miracle stiffeners, you invented skyscrapers of a kind this cosmos had never seen before. You invented stalks and trunks. You invented wood. Why?
If you were a plant gifted with the new gadgets, leaves, you could get a competitive edge in the great grab for sunlight by reaching for the heavens, by lifting yourself above the competition. If you managed to rise toward the sky, if you managed to defy nature’s most basic law, gravity, other plants could crowd and elbow all they wanted to monopolize the sunlight at ground level. But you could do them one better. You could spread a canopy of leaves above them, capturing the sunlight before it ever reached the ground.
Remember, new technologies open new frontiers. New niches are created, not found. With your leaves, you invented a whole new horizon and a whole new resource base for life…a second story that reached to new heights.. You invented leaf highrises, new towers that let you capture the light of the sun long before it could spill over to your competitors down below. You invented trunks of your hard, stiff new building materials, lignin and cellulose. And you manically mass produced so many of these trunks that cellulose and lignin—your new woody super substances, would become “the two most abundant organic compounds on Earth,” Even more astonishing, you invented plumbing systems that could lift 11,000 gallons of water to the sky every day.
You gave one of the biggest fuck yous to gravity in earth’s history. You invented trees. Spires each one of which could lift 200,000 leaves to the sun. And with trees, you spread a new community high above the carpet of mosses and liverworts. Yes, a community carrying out your second great space program. You invented the forest.
You followed the path of most effort, not least. And nature rewarded you for it. Nature loves those who oppose her most.
Which left ground plants with a problem. How do you compete for sunlight when the rays of the sun have been kidnapped high above you, grabbed long before their flood of light can reach the forest floor? You create. You invent new forms and structures.
You do it on the shores and borders of wetlands where forests haven’t gotten a hold. First you, too, adopt the use of leaves. But you up their efficiency. You invent new ways to turn scarcity into plenty. You up your leaves’ productivity.
You have already invented plumbing to lift water above ground level. You have already invented veins. Now you invent ways to make more of those veins. You produce leaves with “dense leave venation”—lots of tightly packed veins. More veins mean more water. So you are “able to dominate land by evolving more efficient hydraulics, or ‘leaf plumbing.’” And more water ups the rate at which your leaves can turn sunlight into sugars and carbohydrates, the rate at which your leaves can tap solar energy and turn mere photons into food and fuel, into life stuff.
Your defiance of nature and your invention of next-tech productivity lets you open new horizons to the evolutionary race. So does the invention of trees. And those inventions up the mass of the biosphere. They up the GAL, the Gross Amount of Life on this earth.
But, again, what other tricks could plants of short stature invent to survive the trees’ monopoly on sunlight? First, more and more of your cousins, more and more massively veiny-leaved plants, show up all over the place. Says Tim Brodribb of the University of Tasmania, one of the discoverers of this “cretaceous productivity stimulus package,” “without this evolutionary step land plants would not have the physical capacity to drive the high productivity that underpins modern terrestrial biology and human civilization.” But there is more.
To solve your tree problem, you, the mid-sized plant go beyond hyperpacking the density of your leaf venation. You take a risk. You take, in fact, what might seem like a step backward.
Your competitors, the trees, are locked in wood. You are not. So you take a chance on a kid-like flexibility. You bet on a relatively woodless, naked, green stem. You “stayed non-woody at first,” explains Linnean Medal for Botany–winner Sherwin Carlquist. And, adds Carlquist, you stay juvenile longer—young and reshapeable. That, says Carlquist, means you can come up with new water-conducting systems, new plumbing systems, to fit the circumstances. And it means, says Carlquist, that you can invent “amazing new forms and wood formulas.” You can do materials engineering. And you can experiment with new shapes and structures. Does this pay off? Says Carlquist, a hearty yes. It makes you the Ninja warriors of the botanical world–in Carlquist’s term, it makes you “the new weeds.”
Then, 250 million years after you invent leaves with super networks of veins, you pull off an even more radical jump. Your great leap outside the box. The change that will remake nature. The change that will remanufacture the status quo and will forever reinvent the way that the evolutionary game will be played. You invent your next law-of-most-effort move. You invent the flower.