Butterflies communicate with each other through a variety of visual, chemical, and behavioral cues. During courtship, male butterflies may use visual displays such as wing-waving or pheromone-releasing to attract females. Females may also use chemical signals, such as pheromones, to attract males. Butterflies also use visual cues to locate food sources and suitable habitats, and they may use chemical signals to mark territories or attract mates. Some species of butterflies also engage in "hilltopping" behavior, where they gather in large groups on hilltops or other prominent locations to mate and socialize.