The Green Marauder

Larry Niven

I WAS TENDING BAR alone that night. The chirpsithra interstellar liner that had left Earth four days earlier had taken most of my customers. The Draco Tavern was nearly empty. The man at the bar was drinking gin and tonic. Two glig— gray and compact beings, wearing furs in three tones of green—were at a table with a chirpsithra guide They drank vodka and consomme, no ice, no flavorings. Four farsilshree had their bulky, heavy environment tanks crowded around a bigger table They smoked smoldering yellow paste through tubes Every so often I got them another jar of paste

The man was talkative I got the idea he was trying to interview the bartender and owner of Earth's foremost multi-species tavern.

"Hey, not me," he protested. "I'm not a reporter. I'm Greg Noyes, with the Scientific American TV show."

"Didn't I see you trying to interview the glig, earlier tonight?"

"Guilty. We're doing a show on the formation of life on Earth. I thought maybe I could check a few things. The gligstith(click)optok—" He said that slowly, but got it right. "—have their own little empire out there, don't they? Earthlike worlds, a couple of hundred. They must know quite a lot about how a world forms an oxygenating atmosphere." He was careful with those polysyllabic words. Not quite sober, then.

"That doesn't mean they want to waste an evening lecturing the natives."

He nodded. "They didn't know anyway. Architects on vacation. They got me talking about my home life. I don't know how they managed that." He pushed his drink away. "I'd better switch to espresso. Why would a thing that shape be interested in my sex life? And they kept asking me about territorial imperatives—" He stopped, then turned to see what I was staring at.

Three chirpsithra, just coming in. One was in a floating couch with life support equipment attached.

"I thought they all looked alike," he said.

I said, "I've had chirpsithra in here for close to thirty years, but I can't tell them apart. They're all perfect physical specimens, after all, by their own standards. I never saw one like that."

I gave him his espresso, then put three sparkers on a tray and went to the chirpsithra table.

Two were exactly like any other chirpsithra; eleven feet tall, dressed in pouched belts and their own salmon-colored exoskeletons, and very much at their ease. The chirps claim to have settled the entire galaxy long ago—meaning the useful planets, the tidally locked oxygen worlds that happen to circle close around cool red dwarf suns—and they act like the reigning queens of wherever they happen to be. But the two seemed to defer to the third. She was a foot shorter than they were. Her exoskeleton was as clearly artificial as dentures: alloplastic bone worn on the outside. Tubes ran under the edges from the equipment in her floating couch. Her skin between the plates was more gray than red. Her head turned slowly as I came up. She studied me, bright-eyed with interest.

I asked, "Sparkers?" as if chirpsithra ever ordered anything else.

One of the others said, "Yes, and serve the ethanol mix of your choice to yourself and the other native. Will you join us?"

I waved Noyes over, and he came at the jump. He pulled up one of the floating chairs I keep around to put a human face on a level with a chirpsithra's. I went for another espresso and a Scotch and soda and (catching a soft imperative hoot from the farsilshree) a jar of yellow paste. When I returned they were deep in conversation.

"Rick Schumann," Noyes cried, "meet Ftaxanthir and Hrofilliss and Chorrikst. Chorrikst tells me she's nearly two billion years old!"

I heard the doubt beneath his exuberance. The chirpsithra could be the greatest liars in the universe, and how would we ever know? Earth didn't even have interstellar probes when the chirps came.

Chorrikst spoke slowly, in a throaty whisper, but her translator box was standard: voice a little flat, pronunciation perfect. "I have circled the galaxy numberless times, and taped the tales of my travels for funds to feed my wanderlust. Much of my life has been spent at the edge of lightspeed, under relativistic time-compression. So you see, I am not nearly so old as all that."

I pulled up another floating chair. "You must have seen wonders beyond counting," I said. Thinking: My God, a short chirpsithra! Maybe it's true. She's a different color too, and her fingers are shorter. Maybe the species has actually changed since she was born!

She nodded slowly. "Life never bores. Always there is change. In the time I have been gone, Saturn's ring has been pulled into separate rings, making it even more magnificent. Tides from the moons? And Earth has changed beyond recognition."

Noyes spilled a little of his coffee. "You were here? When?"

"Earth's air was methane and ammonia and oxides of nitrogen and carbon. The natives had sent messages across interstellar space… directing them toward yellow suns, of course, but one of our ships passed through a beam; and so we established contact. We had to wear life support," she rattled on, while Noyes and I sat with our jaws hanging, "and the gear was less comfortable then. Our spaceport was a floating platform, because quakes were frequent and violent. But it was worth it. Their cities—"

Noyes said, "Just a minute. Cities? We've never dug up any trace of, of nonhuman cities."

Chorrikst looked at him. "After seven hundred and eighty million years, I should think not. Besides, they lived in the offshore shallows in a not very salty ocean. If the quakes spared them, their tools and their cities still deteriorated rapidly. Their lives were short too, but their memories were inherited. Death and change were accepted facts for them, more than for most intelligent species. Their works of philosophy gained great currency among my people, and spread to other species too."

Noyes wrestled with his instinct for tact and good manners, and won. "How? How could anything have evolved that far? The Earth didn't even have any oxygen atmosphere! Life was just getting started; there weren't even trilobites!"

"They had evolved for as long as you have," Chorrikst said with composure. "Life began on Earth one and a half billion years ago. There were organic chemicals in abundance, from passage of lightning through the reducing atmosphere. Intelligence evolved, and eventually built an impressive civilization. They lived slowly, of course. Their biochemistry was less energetic. Communication was difficult. They were not stupid, only slow. I visited Earth three times, and each time they had made more progress."

Almost against his will, Noyes asked, "What did they look like?"

"Small and soft and fragile, much more so than yourselves. I cannot say they were pretty, but I grew to like them. I would toast them according to your customs," she said. "They wrought beauty in their cities and beauty in their philosophies, and their works are in our libraries still. They will not be forgotten."

She touched her sparker, and so did her younger companions. Current flowed between her two claws, through her nervous system. She said, "Sssss…"

I raised my glass, and nudged Noyes with my elbow. We drank to our predecessors. Noyes lowered his cup and asked, "What happened to them?"

"They sensed worldwide disaster coming," Chorrikst said, "and they prepared; but they thought it would be quakes. They built cities to float on the ocean surface, and lived underneath. They never noticed the green scum growing in certain tidal pools. By the time they knew the danger, the green scum was everywhere. It used photosynthesis to turn carbon dioxide into oxygen, and the raw oxygen killed whatever it touched, leaving fertilizer to feed the green scum. The world was dying when we learned of the problem, and then what could we do? A photosynthesis-using scum growing beneath a yellow-white star? There was nothing in our libraries that would help. We tried, of course, but we were unable to stop it. The sky had turned an admittedly lovely transparent blue, and the tide pools were green, and the offshore cities were crumbling before we gave up the fight. There was an attempt to transplant some of the natives to a suitable world; but biorhythm upset made them sterile. I have not been back since, until now."

The depressing silence was broken by Chorrikst herself. "Well, the Earth is greatly changed, and of course your own evolution began with the green plague. I have heard tales of humanity from my companions. Would you tell me something of your lives?"

And we spoke of humankind, but I couldn't seem to find much enthusiasm for it. The anaerobic life that survived the advent of photosynthesis includes gangrene and botulism and not much else. I wondered what Chorrikst would find when next she came, and whether she would have reason to toast our memory.