Final answer:
Repellent pheromones are used as a chemical communication signal to indicate to other members of the same species to stay away, often as a defense mechanism or territorial marking.
Step-by-step explanation:
Repellent pheromones can be used as a signal to stay away. These chemical signals are secreted to elicit specific behavioral responses, such as avoidance, in other members of the same species.
Pheromones play a vital role in the communication between organisms. Among different types of pheromones, some serve as attractants for potential mates and others act as repellents to deter competitors or predators. Many species, especially social insects, utilize pheromones extensively. For example, this salamander releases chemical compounds during injury that elicit avoidance behavior in members of its own species, showcasing a direct application of pheromones for defensive purposes. Even in human communication, certain pheromones, such as axillary steroids, can subtly influence perceptions and behaviors, although their role is less pronounced compared to other species. Overall, pheromones are crucial for a plethora of biological functions, ranging from mating to territorial marking.