Most mammals possess a vomeronasal organ that is involved in pheromone detection, including sex pheromones. Pollinators find flowers through bright colorations, including ultraviolet, and attractant pheromones. Anisole is a precursor to perfumes, insect pheromones, and pharmaceuticals. This organ plays a role in the perception of certain scents and pheromones. Male moths can sense the pheromones of female moths over great distances. Different glands are specialized for different pheromones to attract mates. Moreover, the reward system is differentially activated by the primary pheromones and secondarily attractive odorants. Males have bushier antennae than females, which allow them to sense female pheromones for mating. Stimuli causing induced ovulation include the sexual behaviour of coitus, sperm and pheromones. Yeast release chemical pheromones in order to attract mates. Tarantulas are also very responsive to the presence of certain chemicals such as pheromones. Different glands specialize for different pheromones produced for finding mates. Males can be induced to emit these calls by female pheromones. They are important as pheromones, chemical messenger materials, on which insects depend for communication. Pharaoh ants utilize 3 types of pheromones.