“The changes weren’t just brought about by the plants’ new environment,” Wam put in. “The radiation flux as the meteorite hit may account for some of them, and sunshine must have been cut off for scores of years by the dust and vapor it threw up. Besides, it’s unlikely that there was a single meteorite. The one which moved Slah to its present position was probably the biggest among a full-scale storm. By boiling off part of their mass in the upper air, the others spread metallic poisons clear around the globe. And that could happen again at any time!”
“Ah, we’re clearing the edge of the city at last,” Ugant exclaimed. “Stop fretting, Chybee! The air will be a lot fresher from here on, space-budded poisons or not!”
And, still apparently convinced that chitchat was all the girl needed to help her relax, she continued pointing out sights of interest as the scudder hurtled onward, no longer having to make do with the random grip afforded by bravetree branches within Slah itself, where the wear and tear of traffic might lead to accidents if a single overloaded vehicle added too great a strain, but racing along a specially planted line of toughtrees that slanted around a range of gentle hills. Below, morning sun gleamed on a stream diverted and partly canalized to make a route for freight-pitchens, mindlessly plodding from loq to loq with their massive burdens. Now and then flashes showed how they were being overtaken by courier-pitchens, but of course most urgent messages were conveyed these days by nervograp or by air. Above, looming as vast and brilliant as the sparse white clouds, passenger-floaters were gathering for a landfall at Slah: some, Chybee knew, must have crossed three oceans since the beginning of their voyage. And how much air had been gulped into their ever-flexing bellowers to drive them over such colossal distances? If mere interference by the folk could bring about such incredible modifications, then…!
“Is something wrong?” Ugant said suddenly.
“No—But I mean yes!” she exclaimed. “If plants were changed, and … Well, don’t they also think that some kinds of animal were exterminated too?”
“It’s generally accepted that that’s what happened,” Ugant confirmed gravely. “Many fossils have been found that scarcely resemble the species we’re familiar with.”
“So what about ourselves?”
The scudder, relieved at having reached open country, was swinging along with a pulsating rhythm; now and then it had to overtake another vehicle, so the rhythm quickened, and occasionally it had to slow because traffic grew too dense for speed. For a while Wam and Ugant seemed to be absorbed by it. If they were exuding pheromones, the wind of their rapid passage carried them away.
Finally, though, Ugant sighed loudly.
“To quote my colleague and rival: I wish I could disagree, but I can’t. We were altered by the Greatest Meteorite. We had the most amazing luck, to be candid. Or, putting it another way, our ancestors planned better than they imagined. Would you believe that some of the records we’ve recovered suggest we were in a fair way to extinction before the meteorite?”
“Ugant!”—in a warning tone from Wam. “Galdu hasn’t published her findings yet, and they may be adrift.”
Chybee was feeling light-pithed by now. Never before had she imagined that her idols, the scientists, could argue as fiercely as any psychoplanetarist maintaining that her, or his, version of life on the moons of Stolidchurl must be more accurate than anybody else’s.
She said, “Oh, spin your webs for me! You said I was coming along today to make up my own mind!”
But they both took the remark seriously. Ugant said, “If we can’t convince her, who can we hope to convince?”
Wam shrank back, abashed. “You’re right. And Galdu’s primary evidence, at least, does seem convincing.”
“She’s a pastudier, remember, working in a field you and I know little about … What it comes to, Chybee, is this.” Adapting herself to the swaying of the scudder as it rose to pass over the lowest point along the line of hills that up to now they had been paralleling, Ugant drew closer. “None of our biologists can see how we could have escaped dying out ourselves unless some genius of the far past foresaw the need to protect us against just such an event as the fall of the Greatest Meteorite. Almost all the large animals on the planet disappeared because they were—like us—symbiotes. The regular adaptive resource of the ‘female’ sex among them was to become more male. In the end, naturally, this resulted in a zero bud-rate. But because we’d been somehow altered, the process came to a dead stop in the folk. In you and me, that means.”