Improvisation is an often underappreciated art. It requires paying close attention to what’s going on around you, being prepared for the unexpected, using whatever’s handy in unusual and even “wrong” ways, and of course, taking the risk of falling flat on your face. Thus life evolves—making use of off-the-shelf stuff in the environment, the stray cosmic ray that tweaks some DNA, even biological “inventions” evolved for wildly different purposes. Scientists improvise experiments, scrounging around for unused magnets, forgotten phototubes; actors improvise tragedy and jokes. Even the most closely choreographed dance can require immediate improvisation should a ballerina slip and fall. Life is improv, if we let it be. But it isn’t all that easy to be spontaneous.