Shadows of Forgotten Ancestors

The beings of our planet are imperfectly linked and coordinated; and there is certainly nothing like a collective intelligence of all the life on Earth—in the sense that all the cells of a human body are subject, within stringent constraints, to a supervening volition. Still, the alien biologist might be excused for lumping together the whole biosphere—all the retroviruses, mantas, foraminifera, mongongo trees, tetanus bacilli, hydras, diatoms, stromatolite-builders, sea slugs, flatworms, gazelles, lichens, corals, spirochetes, banyans, cave ticks, least bitterns, caracaras, tufted puffins, ragweed pollen, wolf spiders, horseshoe crabs, black mambas, monarch butterflies, whiptail lizards, trypanosomes, birds of paradise, electric eels, wild parsnips, arctic terns, fireflies, titis, chrysanthemums, hammerhead sharks, rotifers, wallabies, malarial plasmodia, tapirs, aphids, water moccasins, morning glories, whooping cranes, komodo dragons, periwinkles, millipede larvae, angler fish, jellyfish, lungfish, yeast, giant redwoods, tardigrades, archaebacteria, sea lilies, lilies of the valley, humans, bonobos, squid and humpback whales—as, simply, Earthlife. The arcane distinctions among these swarming variations on a common theme may be left to specialists or graduate students. The pretensions and conceits of this or that species can readily be ignored. There are, after all, so many worlds about which an extraterrestrial biologist must know. It will be enough if a few salient and generic characteristics of life on yet another obscure planet are noted for the cavernous recesses of the galactic archives.

* Seawater itself is opaque to ultraviolet light beyond a certain depth, and the early oceans were very likely covered by a slick of ultraviolet-absorbing organic molecules. The seas were safe.* A biochemical imperfection exploited by the beer, wine, and liquor industries, which profitably manufacture this addictive and dangerous drug, C₂H₅OH (where C stands for a carbon atom, O for oxygen, and H for hydrogen). Millions of people worldwide die from imbibing it each year. Or, looked at another way, distillers have been exploited by the fermenting bacteria and yeast, who have gotten us to arrange for their growth and reproduction on a worldwide, industrial scale—because we love to drink ourselves senseless on microbial wastes. If they could speak, perhaps they would boast about how cleverly they’ve domesticated the humans. Yeasts also colonize dark, moist, oxygen-poor parts of the human body, another way in which we serve them.† Another example was given by the ancient Greek philosopher Heraclitus: “The sea,” he said, “is most pure and most polluted water: for fish, drinkable and life-preserving; for men, undrinkable and death-dealing.”²* The genetic code of the mitochondrion is just a little different from that of the nucleus—as if it had evolved so that the nuclear DNA could not tell the mitochondria what to do, a token of independence. For example, AGA means STOP for mitochondrial nucleic acids, whereas for the nucleic acids that hail from the nucleus of a cell, it codes for a particular amino acid, arginine.³ The mitochondria simply ignore instructions from the capital, which to them are mainly gibberish with occasional lucid passages; they follow the commands of their own feudal leader, the mitochondrial DNA.* Ninety-five percent seems awfully close to 100%, and it’s disquieting to be reminded that the great rumbling, internal tectonic engine can inadvertently kill off so many of us up here because of some hiccups down there.* In principle the ecological machine could continue as long as the Sun continues to shine, estimated at another 5 billion years. It’s hard not to wonder—we carnivores at the apex of the food chain, the beneficiaries of a process with a thousandth of a percent efficiency—if there might not be some more efficient way for us to harness the Sun.

Chapter 8

SEX AND DEATH

[S]ex endows the individual with a dumb and

powerful instinct, which carries his body and

soul continually towards another; makes it one

of the dearest employments of his life to select

and pursue a companion, and joins to

possession the keenest pleasure, to rivalry the

fiercest rage, and to solitude an eternal

melancholy. What more could be needed to

suffuse the world with the deepest meaning

and beauty?

GEORGE SANTAYANA,

The Sense of Beauty (1896)¹

Death is the great reprimand which the will to

live, or more especially the egoism which is

essential to this, receives through the course of

nature; and it may be conceived of as a

punishment for our existence. It is the painful

loosening of the knot which the act of

generation had tied …

ARTHUR SCHOPENHAUER,

The World as Will and Idea, Supplements²