It is hard to believe that Reynolds started having his stories published in 1990. I still think of him as a newer writer. "Scales" first appeared in 2009 as part of the Guardian Books Podcast. It was reprinted in Lightspeed Magazine's May 2011 issue.
This is the first military fiction written by Reynolds that I remember. When I finished it I thought of similar themes from Robert Heinlein's "Starship Troopers" and Joe Haldeman's "The Forever War". Somehow Reynolds was able to fit many big ideas including humanity at war with an alien race, the evolution of humanity, the life of a soldier, and it all happened in a short story. Usually Reynolds receives credit for his novels but I think he is a master of the short form. This stand alone story deserves to be recognized. I plan on checking out more of his short fiction. This is the second of his short stories I have read and both were very good.
Highly recommended. Not enough room to develop the characterization but the ideas and plot carry it at this short length.