“I don’t get it,” Albert said. “Why can’t you continue to collaborate after he grows up? I thought Neltoq was grown up already.”

“You don’t read much, do ya, kid?” said Gelb. He flicked ash from his cigarette onto the station floor. “For the Ultoq, growing up’s the same as death.”

The Ultoq homeworld was a global mass of structures not unlike mangrove swamps on Earth, with only shallow seas and upland plains in between. Competition was fierce, so Ultoqs had evolved a complex life cycle to prevent their young from competing with adults. Ultoq newborns were planktonic, released in vast numbers with only a few reaching the second stage and moving back to shore. After a metamorphosis, the primate-like Ultoq that most humans were familiar with emerged. With binocular vision, a highly-developed forebrain, and opposable fingers on all seven limbs to facilitate moving and feeding in the vast and complex root structures, the second stage was intelligent enough to develop a civilization and tools if it lasted longer. Evolution, however, had dictated that the second stage existed merely to gather food; once a certain stage of growth was reached, the Ultoq returned to the sea and underwent a final metamorphosis into a sessile, mindless tunicate-like filter feeder, which lived only to send out vast quantities of sperm or eggs into the sea to begin the cycle anew.

It wasn’t until, by chance, a second-stage Ultoq discovered the grinyth plant that their civilization had developed. Grinyth fruit and leaves produced a compound that retarded the onset of the final metamorphosis–as long as there was grinyth in its system, an Ultoq would not proceed to the last stage of its life. Even as Ultoq Civilization developed, though, the need to maintain their numbers was paramount. Thus, after a time, they would all cease intake of grinyth–or its synthesized derivatives–and “grow up,” losing all memory and ability to propagate the species.

“Heavy stuff, man,” said Albert. “Heavy stuff.”