It's astonishing to watch how fast science fiction and fantasy can take a newborn genre and strip it to the bone.I've been thinking lately about urban fantasy, about its origins and the permutations it went through over the last 30 years; about how it was born around the same time as cyberpunk, and how its fate was in some ways similar, and in some ways very, very different.Mostly, I'm thinking about how we reduce genres to their component parts as efficiently as the crew of a whaler breaks down a carcass. It's one of the things that makes me feel very ambivalent about science fiction and fantasy publishing.Let us go back to the origins of urban fantasy as a distinct genre. It's the mid-1980s. Epic fantasy is still relatively young, but some of the big names are already hip-deep in multi-book sagas. Tolkein's long shadow still hovers over the field. Secondary worlds with quests and magic swords and dragons are the essence of what people think of when they think of fantasy.There have always been a trickle of fantasies set in the modern world, of course, including by big names like Gene Wolfe and Ray Bradbury. But many of them, as Jo Walton noted, were children's books, like Susan Cooper's The Dark is Rising. There was also the long pulp tradition of "weird tales" that involved monsters and ghosts, and there had even been a nascent paranormal detective strand to short fantasy. There were Anne Rice's modern vampire series, and the dark fantasy/horror novels that moved in the wake of that publishing juggernaut.But urban fantasy isn't a genre yet, no one has recognized or grouped the books that do exist, there's no real name and certainly no editors or agents pestering people for "more urban fantasy."What there are, starting around 1986 and 1987, are a few books in which magic intrudes into the grimy real world.