This is a book that I picked up when I belonged to a Sci-Fi book of the month club many years ago. It was quickly added to my librairy and I re-read it at least once a year.
Mr. Brin idea for the story began with contemplation of several species of American Southwest lizards that can reproduce parthenogenetically (mothers giving birth to clones). He then discovered aphids, which reproduce cloning and through normal sexual means, and then asked himself "What if humans can do the same?"
The result is a world run by women, but reliant on men to "spark" the creation of the pleccenta in winter to enable cloning, but "regular" sex in the summer result in your varients; boys and girls woith the genetic of both parents.
"Glory Season" follows the life of a summer-concieved mirror-image twin, Maia, after she and her sister, Leie, are sent off into the world at 16. The twins' plan to pass themselves off as clones, in order to start their own clone clan, but cercimstances soon find them separated and following their own paths. Maia soon finds herself caught up in global polictics surrounding an alien man from Earth, and her own feeling regarding him. After all she has been brought up that men are good only for "sparking" and not much else.
David Brin could have taken this world to a very feminist Eutopia, but instead, adds a sect of women who would like their world to be only women, while maintaining a balance of those of an opposing view. Men are shown, at the begining, from the viewpoint of shelter children who believe they are nothing more than raging animals, but through Maia, you see how she begins to view everyone so very differently than how she was brought up. By the end of the book, you see how balanced the world truly is, and how much control men do have in this woman dominated society.