abstract:"The Winnowing" is a science fiction short story by Isaac Asimov. The story was written at the request of William Levinson, editor of the US publication Physician's World, but when the latter ceased publication, the story was returned to the author, who then sold it to Analog.
But one potential contributing factor comes from a fascinating piece in National Affairs by Marc Dunkelman, who fears thewinnowing out of so-called "middle-tier relationships" for the American citizen.
This says that thewinnowing of the gene pool, which drives evolution, can favour or destroy entire social groups as single entities, as well as working at the level of individual organisms.