 How long did it take for Venus’s conditions to mutate its human colonies? What is the purpose of these mutations?
DOUBLECROSS by JAMES Mac CREIGH Revolt was brewing on Venus, led by the descendant of the first Earthmen to land. [Transcriber's Note: This etext was produced from Planet Stories Winter 1944. Four or five generations ago they were. "They had to acclimate themselves to Venus's climate. They think there will be hordes of immigrants from Earth, now that we know Venus is habitable. And there's some sort of a paltry underground group that is spreading the word that the immigrants will drive the native Venusians—the descendants of the first expedition, that is—right down into the mud. We have agreed that, if the Earth-ship returns, it means disaster for Venus.
 Four or five generations. Acclimation.
 Three or four generations. Hunting.  Four or five generations. Acclimation.  Four or five generations. Bomb making.  One or two generations. Revolution.