The translator went on. "Our metabolic rate is the lowest of any creature we know of. We live several thousand revolutions of any recorded planet and our rate of increase is extremely low; under the most favorable circumstances, we can do no more than double our numbers in two hundred generations."
"This doesn't sound as if they were masters of biological science," rustled Taphetta.
Halden stirred uneasily. It wasn't turning out at all the way he had expected.
"At the time we left," the message continued, "we found no other intelligent race, though there were some capable of further evolution. Perhaps our scout ships long ago met your ancestors on some remote planet. We were never very numerous, and because we move and multiply so slowly, we are in danger of being swept out of existence in the foreseeable future. We prefer to leave while we can. The reason we must go developed on our own planet, deep beneath the cities, in the underworks, which we had ceased to inspect because there was no need to. This part was built to last a million generations, which is long even for us."
Emmer sat upright, annoyed at himself. "Of course! There are always sewers and I didn't think of looking there!"
"In the last several generations, we sent out four expeditions, leisurely trips because we then thought we had time to explore thoroughly. With this planet as base of operations, the successive expeditions fanned out in four directions, to cover the most representative territory."
Kelburn stiffened, mingled pride and chagrin on his face. His math had been correct, as far as he had figured it. But had there been any reason to assume that they would confine their exploration to one direction? No, they would want to cover the whole Milky Way.
Taphetta paled. Four times as many humans to contend with! He hadn't met the other three-fourths yet—and, for him, it wasn't at all a pleasant thought.
"After long preparation, we sent several ships to settle one of the nearer planets that we'd selected on the first expedition. To our dismay, we found that the plague was there—though it hadn't been on our first visit!"