The vomeronasal organ (VNO) is found inside the noses of various animals  While its structural development and function are clearer in other animals, most humans have a VNO that is detectable, though only microscopically  When researchers have been able to stimulate VNO cells in humans, the subjects have reported experiencing subtle smell sensations
It seems, then, that the VNO, though not completely understood, is a functioning sensory organ in most humans
Relative to its occurrence in certain other animals, the human VNO appears to be anatomically rudimentary and underdeveloped.