is dauer pheromone of caenorhabditis elegans really a pheromone animals respond to signals and cues in their environment the difference between a signal eg a pheromone and a cue eg a waste product is that the information content of a signal is subject to natural selection whereas that of a cue is not the model freeliving nematode caenorhabditis elegans forms an alternative developmental morph the dauer larva in response to a socalled dauer pheromone produced by all worms we suggest that the production of dauer pheromone has no fitness advantage for an individual worm and therefore we propose that dauer pheromone is not a signal but a cue thus it should not be called a pheromone