Lost SF Stories

I wrote up some SF stories I'm looking for title/author info on.

War
An episodic story of humans gradually evolving during a thousand year long war with an alien species. First their giant ships divide into classes, and eventually the classes diverge genetically and culturally as well. Instead of being generalists, humans become instinctual - pilots have their sex drives linked to guiding missiles, etc. Eventually none of the beings actually know what's happening or why. Amazing story.

Duplication
a trombonist discovers a simple way to duplicate any object. He dups his trombone and sells them to buy some other instruments. Then he dups himself and creates a band. Eventually there are hundreds of him running around, then millions, then a huge war. Turns out that duplication isn't quite perfect, and introduces slight changes. So he sees many versions of himself. Eventually they all die out and he goes back to his poor life.

Wurple
A species with 4 sexes reproduces by taking any group of 3 and "wurpling", which produces a being of the 4th sex. There is usually one sex which is more common, and looked down upon - nobody wants to mate with them, which produces more and more of that type. Since the 4 types have distinct personalities, the population goes through drastic sex-balance shifts.