Borders of Infinity

by Lois McMaster Bujold

The fifty thousand Firsters from Earth had only meant to be the spearhead of Barrayar’s colonization. Then, by a gravitational anomaly, the wormhole jump through which the colonists had come had shifted closed—violently, irrevocably, and without warning. The terraforming which had begun, so careful and controlled in the beginning, collapsed along with everything else. Imported Earth plant and animal species had escaped everywhere to run wild, as the humans turned their attention to the most urgent problems of survival. Biologists still mourned the mass extinctions of native species that had followed, the erosions and droughts and floods, but really, Miles thought, over the centuries of the Time of Isolation the fittest of both worlds had fought it out to a perfectly good new balance. If it was alive and covered the ground who cared where it came from? We are all here by accident. Like the roses.