17

I sat in our living room, late that night, after Hollus had returned to his starship. I’d taken two pain pills, and I was letting them settle before I went to bed — the nausea sometimes made it hard to keep the pills down.

Maybe, I thought, the Forhilnor was right. Maybe there was no smoking gun that I would accept. He said it was all there, right in front of my eyes.

There are none so blind as those who will not see;besides the Twenty-ninth Scroll, that’s one of my favorite bits of religious writing.

But I wasn’t blind, dammit. I had a critical eye, a skeptic’s eye, the eye of a scientist.

It stunned me that life on assorted worlds all used the same genetic code. Of course, Fred Hoyle had suggested that Earth — and presumably other planets — were seeded with bacterial life that drifted in from space; if all the worlds Hollus had visited were seeded from the same source, the genetic code would, of course, be the same.

But even if Hoyle’s theory isn’t true — and it’s really not a very satisfying theory, since it simply pushes the origin of life off to some other locale that we can’t easily examine — maybe there were good reasons why only those twenty amino acids were suitable for life.

As Hollus and I had discussed before, DNA has four letters in its alphabet: A, C, G, and T, for adenine, cytosine, guanine, and thymine, the bases that form the rungs of its spiral ladder.

Okay — a four-letter alphabet. But how long are the words in the genetic language? Well, the purpose of that language is to specify sequences of amino acids, the building blocks of proteins, and, as I said, there are twenty different aminos used by life. Obviously, you can’t uniquely identify each of those twenty with words just one letter long: a four-letter alphabet only provides four different one-letter words. And you couldn’t do it with words two letters long: there are only sixteen possible two-letter words in a language that has just four characters. But if you use three-letter words, ah, then you’ve got an embarrassment of riches, a William F. Buckley-style biochem vocabulary of a whopping sixty-four words. Set aside twenty to name each amino acid, and two more for punctuation marks — one for starting transcription and another for stopping. That means only twenty-two of the sixty-four possible words are needed for DNA to do its work. If a god had designed the genetic code, he must have looked at the surplus vocabulary and wondered what to do with it.

It seems to me that such a being would have considered two possibilities. One was to leave the remaining forty-two sequences undefined, just as there are letter sequences in real languages that don’t form valid words. That way, if one of those sequences cropped up in a string of DNA, you’d know that a mistake had occurred in copying — a genetic typo, turning the valid code A-T-A into, say, the gibberish A-T-C. That would be a clear, useful signal that something had gone wrong.

The other alternative would be to live with the fact that copying errors were going to occur, but try to reduce their impact by adding synonyms to the genetic language. Instead of having one word for each amino acid, you could have three words that mean the same thing. That would use up sixty of the possible words; you could then have two words that mean start and two more that mean stop, rounding out the DNA dictionary. If you tried to group the synonyms logically, you could help guard against transcription errors: if A-G-A, A-G-C, and A-G-G all meant the same thing, and you could only clearly read the first two letters, you’d still have a good shot at guessing what the word meant even without knowing the third letter.

In fact, DNA does use synonyms. And if there were three synonyms to specify each amino acid, one might look at the code and say, yup, someone had carefully thought this out. But two amino acids — leucine and serine — are specified by six synonyms each, and others by four, three, two, or even just one: poor tryptophan is specified only by the word T-G-G.

Meanwhile, the code A-T-G can mean either the amino acid methionine (and there are no other genetic words for it) or, depending on context, it can be the punctuation mark for “start transcription” (which also has no other synonyms). Why on Earth — or anyplace else — would an intelligent designer make such a hodgepodge? Why require context sensitivity to determine meaning when there were enough words available to avoid having to do that?

And what about the variations in the genetic code? As I’d told Hollus, the code used by mitochondrial DNA differs slightly from that used by the DNA in the nucleus.

Well, in 1982, Lynn Margulis had suggested that mitochondria — cellular organelles responsible for energy production — had started out as separate bacterial forms, living in symbiosis with the ancestors of our cells, and that eventually these separate forms were co-opted into our cells, becoming part of them. Maybe . . . God, it was a long time since I’d done any serious biochemistry . . . but maybe the mitochondrial and nuclear genetic codes had indeed originally been identical, but, when the symbiosis began, evolution favored mutations that allowed for a few changes in the mitochondrial genetic code; with two sets of DNA existing within the same cell, maybe these few changes served as a way to distinguish the two forms, preventing accidental mingling.

I hadn’t mentioned it to Hollus, but there were also some minor differences in the genetic code employed by ciliated protozoans — if I remember correctly, three codons have different meanings for them. But . . . I was blue-skying; I knew that . . . but some said that cilia, those irreducibly complex organelles whose death had brought about my own lung cancer, had started out as discrete organisms, as well. Maybe those ciliated protozoa that had a variant genetic code were descended from some cilia who had been in symbiosis with other cells in the past, developing genetic-code variations for the same safety-net reasons mitochondria had but, unlike the cilia we still retained, had subsequently broken off the symbiosis and returned to stand-alone life.

It was a possibility, anyway.

Still, when I’d been a kid in Scarborough, we’d shared a back fence with a woman named Mrs. Lansbury. She was very religious — a “Holy Roller,” my dad would say — and was always trying to persuade my parents to let her take me to church on Sundays. I never went, of course, but I do remember her favorite expression: the Lord works in mysterious ways.

Perhaps so. But I found it hard to believe he would work in shoddy, haphazard ones.

And yet —

And yet what was it Hollus had said about Wreed language?

It, too, relies on context sensitivity and the unusual use of synonyms. Maybe at some Chomsky-esque level, I just wasn’t wired properly to see the elegance in the genetic code. Maybe T’kna and his kin found it perfectly reasonable, perfectly elegant.

Maybe.


Suddenly the cat was out of the bag.

I hadn’t said a word to anyone about the Merelcas’s mission being, at least in part, to look for God. And I was pretty sure the gorillas in Burundi had been mum on the topic. But all at once, everyone knew.

There was a row of newspaper boxes by the entrance to North York Centre subway station. The headline on today’s Toronto Star said, “Aliens Have Proof of God’s Existence.” The headline on the Globe and Mail proclaimed, “God a Scientific Fact, Say ETs.” The National Post declared, “Universe Had a Creator.” And the Toronto Sun proclaimed just two giant words, filling most of its front page: “God lives!”

Usually I grabbed the Sun for light reading on the way to work, but for in-depth coverage, nothing beats the Mop and Pail; I dropped coins into the gray box and took a copy. And I stood there, in the crisp April air, reading everything above the fold.

A Hindu woman in Brussels had asked Salbanda, the Forhilnor spokesperson who met periodically with the media, the simple, direct question of whether he believes in any gods.

And he’d answered — at length.

And of course, cosmologists all over the planet, including Stephen Hawking and Alan Guth, were quickly interviewed to find out if what the Forhilnor had said made sense.

Religious leaders were jockeying for position. The Vatican — with rather a history of backing the wrong horse in scientific debates — was reserving comment, saying only that the pope would address the issue soon. The Wilayat al-Faqih in Iran denounced the alien’s words. Pat Robertson was calling for more donations, to help his organization study the claims. The moderator of the United Church of Canada embraced the revelations, saying that science and faith were indeed reconcilable. A Hindu leader, whose name, I noted, was spelled two different ways in the same article, declared the alien’s statements to be perfectly compatible with Hindu belief. Meanwhile, the ROM’s own Caleb Jones pointed out, on behalf of CSICOP, that there was no need to read anything mystical or supernatural into any of the Forhilnor’s words.

When I arrived at the ROM, the usual round of UFO nuts had been joined by several different religious groups — some in robes, some holding candles, some chanting, some kneeling in prayer. There were also several police officers, making sure that staff members — including but by no means limited to myself — made it safely into the museum; once the main doors opened for the day, they’d extend the same courtesy to patrons.

Laser-printed leaflets were blowing down the sidewalk; one that caught my eye showed Hollus, or another Forhilnor, with his eyestalks exaggerated to look like a devil’s horns.

I entered the museum and made it up to my office. Hollus wavered into existence a short time later. “I have been thinking about the people who blew up the abortion clinic,” he said. “You said they were religious fundamentalists.”

“Well, one presumes so, yes. They haven’t been caught yet.”

“No smoking gun,” said Hollus.

I smiled. “Exactly.”

“But if they are, as you suspect, religious people, why is that relevant?”

“Blowing up an abortion clinic is an attempt to protest a perceived moral outrage.”

“And . . . ?” said Hollus.

“Well, on Earth, the concept of God is inextricably linked to issues of morality.”

Hollus listened.

“In fact, three of our principal religions share the same Ten Commandments, supposedly handed down by God.”

Susan once quipped that the only piece of scripture I knew was the Lawgiver’s Twenty-ninth Scroll:


Beware the beast Man, for he is the devil’s pawn. Alone among God’s primates, he kills for sport, or lust, or greed. Yea, he will murder his brother to possess his brother’s land. Let him not breed in great numbers, for he will make a desert of his home and yours. Shun him. Drive him back into his jungle lair, for he is the harbinger of death.


It’s what Cornelius read to Taylor near the end of Planet of the Apes. Powerful words, and, like Dr. Zaius, I’ve always tried to live by their injunction. But Susan isn’t quite right. Back when I was a student at U of T, lo those many years ago, I occasionally audited classes by Northrop Frye, the great teacher of English; I also snuck into lectures given by Marshall McLuhan and Robertson Davies, the other two members of U of T’s internationally acclaimed humanities triumvirate. It was heady, listening to such staggering intellects. Frye contended that you could not appreciate English literature without knowing the Bible. Perhaps he was right; I’d once made it through about half the Old Testament and had skimmed the color-coded “actual words of Jesus” in a King James version I’d bought at the campus bookstore.

But, basically, what Susan said was true. I didn’t know the Bible well, and I didn’t know the Qur’an or any other holy book at all.

“And these Ten Commandments are?” asked Hollus.

“Umm, well, thou shalt not kill. Thou shalt not commit adultery. Thou shalt not . . . umm, something about an ass.”

“I see,” said Hollus. “But as far as we have been able to determine, the creator has never communicated directly with anyone. Indeed, the Wreeds — who, as you know, spend half their lives actively seeking such communication — claim no success. I am not sure how such commandments would be passed on to any lifeform.”

“Well, if I remember the movie correctly, God wrote them with a finger of fire on stone tablets.”

“There is a movie of this event? Would that not be your smoking gun?”

I smiled. “The movie is a drama, a story. The Ten Commandments were supposedly handed down thousands of years ago, but the movie was made about half a century ago.”

“Oh.”

“Still, many humans believe that they are in direct or indirect communication with God — that he listens to prayers. “They are delusional,” said Hollus. His eyestalks came to rest. “Forgive me,” he said. “I know you are dying. Have you been moved to pray?”

“No. But my wife Susan does.”

“Her prayers have not been answered.”

“No,” I said softly. “They haven’t.”

“How do members of your species reconcile the act of prayer with the reality that most prayers go unanswered?”

I shrugged a little. “We say things like ‘Everything happens for a reason.’”

“Ah, the Wreed philosophy,” said Hollus.

“My little boy asked me if I’d done something wrong — if that’s why I’d gotten cancer.”

“And did you do something wrong?”

“Well, I’ve never smoked, but I suppose my diet could have been better.”

“But did you do anything morally wrong? Those Ten Commandments you mentioned — did you break any of those?”

“To be honest, I don’t even know what all ten are. But I don’t think I’ve ever done anything horrible. I’ve never committed murder. I’ve never cheated on my wife. I’ve never stolen anything — at least not as an adult. I’ve never—” Thoughts of Gordon Small, and events of three decades past, came to mind. “Besides, I can’t believe a caring God would punish anyone, no matter what the transgression, with what I’m going through.”

“ ‘A caring God,”’ repeated Hollus. “I have also heard the phrases ‘a loving God,’ and ‘a compassionate God.’ ” His eye-stalks locked on me. “I think you humans apply too many adjectives to the creator.”

“But you’re the ones who believe that God has a purpose for us,” I said.

“I believe the creator may have a specific reason for wanting a universe that has life in it, and, indeed, as you say, for wanting multiple sentiences to emerge simultaneously. But it seems clear beyond dispute that the creator takes no interest in specific individuals.”

“And that’s the generally held opinion amongst members of your race?” I asked.

“Yes.”

“Then what is the source of Forhilnor morality? How do you tell right from wrong?”

Hollus paused, either searching for an answer or considering whether he wanted to answer at all. Finally, he said, “My race has a violent past,” he said, “not unlike your own. We are capable of feats of great savagery — indeed, we do not need weapons to easily kill another member of our own kind. The right things to do are those that keep our violence in abeyance; the wrong things are those that bring it to the fore.” He shifted his weight, redeploying his six feet. “Our race has not fought a war for three generations; since we have the capability to destroy our world, this is a good thing.”

“I wonder if violence is innate in all intelligent species,” I said. “Evolution is driven by struggles for dominance. I’ve heard it suggested that no herbivore could ever develop intelligence because it doesn’t take any cunning to sneak up on a leaf.”

“It does create an odd dynamic,” said Hollus. “Violence is required for intelligence, intelligence gives rise to the ability to destroy one’s species, and only through intelligence can one overcome the violence that gave rise to that intelligence.”

“We’d call that a Catch-22,” I said. “Maybe we create the idea of a caring God and morality to foster self-preservation. Perhaps any race that doesn’t have morality, that doesn’t suppress its violent urges in a desire to please a god, is doomed to destroy itself once it gets the technology to do so.”

“An interesting thought,” said Hollus. “Belief in God conferring a survival advantage. Evolution would then select for it.”

“Does your race still worry about destroying itself?” I asked.

Hollus bobbed, but I think it was a gesture of negation, not affirmation. “We have a unified planetary government, and much tolerance for diversity. We have eliminated hunger and want. There is little reason for us to come into conflict with each other anymore.”

“I wish I could say the same thing about my world,” I said. “Since this planet was fortunate enough to have life arise on it, it would be a shame to see it snuffed out because of our own stupidity.”

“Life did not arise here,” said Hollus.

“What?” I was completely lost.

“I do not believe that there was a biogenerative event in Earth’s past; I do not believe life began here.”

“You mean it drifted here from deep space? Fred Hoyle’s panspermia hypothesis?”

“Possibly. But I suspect it is more likely that it began relatively locally, on Sol IV.”

“Sol — you mean Mars?”

“Yes.”

“How would it get here from there?”

“On meteors.”

I frowned. “Well, there’ve been a couple of Martian meteorites found over the years that some said had fossils in them. But they’ve been pretty thoroughly discredited.”

“It would only take one.”

“I suppose. But why don’t you think life is native to this planet?”

“You said you thought life had emerged on this world as much as four billion years ago. But that early in your solar system’s history, this planet was still routinely undergoing extinction-level impact events, as large comets and asteroids frequently slammed into it. It is extremely unlikely that conditions suitable for life could have been maintained during that period.”

“Well, Mars is no older than Earth, and surely it was undergoing bombardment, too.”

“Oh, doubtless so,” said Hollus. “But although Mars clearly had running water in its past — its surface today is really quite impressive to stand upon; the erosion features are incredible — it never had large or deep oceans like those here on Earth. If an asteroid hits land, heat from the impact might raise temperatures for a matter of months. But if it hits water, which, after all, covers most of Earth’s surface now as well as billions of years ago, the heat would be retained, raising the planet’s temperature for decades or even centuries. Mars would have had a stable environment for the development of life perhaps as much as half a billion years before Earth did.”

“And then some of it was transferred here, on meteors?”

“Exactly. About one thirty-sixth of all the material that gets knocked off Mars by meteor impacts should eventually be swept up by Earth, and many forms of microbes can survive freezing. It neatly explains why full-fledged life is recorded in the oldest rocks here, even though the environment was too volatile for it to develop domestically.”

“Wow,” I said, well aware that my response wasn’t adequate. “I suppose one meteor with life on it might have made it here. After all, every lifeform on this planet shares a single common ancestor.”

Hollus sounded astonished. “All life on this planet shares one common ancestor?”

“Of course.”

“How do you know that?”

“We compare the genetic material of different lifeforms, and, judging by how much it diverges, we can tell how long ago they had an ancestor in common. For instance, you’ve seen Old George, the stuffed chimpanzee we have in the Budongo Rain Forest diorama?”

“Yes.”

“Well, humans and chimps differ genetically by only 1.4 percent.”

“If you will forgive me for saying so, it does not seem right to stuff and display so close a relative.”

“We don’t do that anymore,” I said. “That mount is more than eighty years old.” I decided not to mention the stuffed Australian aborigine they used to have on display at the American Museum of Natural History. “In fact, it’s largely through genetic studies that the concept of ape rights gained credence.”

“And such studies show all life on this planet to have a common ancestor?”

“Of course.”

“Incredible. On both Beta Hydri and Delta Pavonis, we believe there were multiple biogenerative events. Life on my world, for instance, arose at least six times during an initial 300-million-year period.” He paused. “What is the highest level in your hierarchical biological classification system?”

“Kingdom,” I said. “We generally recognize five: Animalia, Plantae, Fungi, Monera, and Protista.”

“Animalia are the animals? And Plantae the plants?”

“Yes.”

“All animals are grouped together? Likewise all plants?”

“Yes.”

“Fascinating.” His spherical torso bobbed deeply. “On my world, we have a level above that, consisting of the six — well, ‘domains’ might be an appropriate translation — the six domains from the six separate creation events; separate kinds of animals and plants exist in each. For instance, our pentapeds and octopeds are, in fact, completely unrelated; cladistic studies have demonstrated that they share no common ancestor.”

“Really? Still, you should be able to use the DNA technique I described to determine evolutionary relationships amongst members of the same domain.”

“The domains have commingled over the eons,” Hollus said. “The genome of my own species contains genetic material from all six domains.”

“How is that possible? As you said about Spock, the idea of members of different species — even from the same domain — having offspring is ludicrous.”

“We believe viruses played a substantial role over millions of years in moving genetic material across domain boundaries.”

I thought about that. It had been suggested on Earth that unnecessary material transferred into lifeforms by viruses accounted for much of the junk DNA — the ninety percent of the human genome that did not code for protein synthesis. And, of course, geneticists today were deliberately transferring cow genes into potatoes and so on.

“All six domains are based on DNA?” I asked.

“As I have said, every complex lifeform that we have discovered is based on DNA,” said Hollus. “But with DNA crossing domains throughout our history, the kind of comparative study you suggest is not something we have had much success with. Animals that are clearly very closely related, based on the gross details of body form, may have significant recent intrusions of new DNA from another domain, which would make the percentage of deviation between the two species deceptively large.”

“Interesting,” I said. A thought occurred to me, too crazy to voice out loud. If, as Hollus said, DNA was universally used in all lifeforms, and the genetic code was the same everywhere, and lifeforms even from different domains could incorporate each other’s DNA, then why couldn’t lifeforms from different worlds do the same thing?

Maybe Spock wasn’t so improbable after all.

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