“Defiance” by Susan Kaye Quinn is set in a dystopian future where some of humanity has ascended, leaving the legacy humans to survive. It is a tie-in to her Singularity young adult series. I read it in the collection The Future Chronicles – Special Edition. Until February 29, 2016, you can get The Future Chronicles – Special Edition, or any one of a selection of free books, by signing up to Discover Sci-Fi.
Although this seemed like a part of a much longer story, it was worth reading and has piqued my interest to read the series. I felt right from the start that this was an interesting world and was strong enough to build a book series upon. It makes me think that writing short stories is a valid way to test out ideas which could later be expanded into a novel.