Vomeronasal organ

The vomeronasal organ (VNO), also known as Jacobson’s organ, is a specialized structure inside many animals’ noses that detects certain chemical signals called pheromones. These signals are involved in social and reproductive behaviors, like marking territory or finding a mate. The VNO helps animals interpret these chemical cues to understand their environment and other creatures' intentions. In humans, the VNO is present during development but is generally considered vestigial, meaning it may not function actively in adult life. Overall, it plays a key role in how many species perceive and respond to chemical communication.