Social insect pheromones

Definition

Chemical signals produced by eusocial insects—primarily Hymenoptera (ants, bees, wasps), Isoptera/Blattodea (termites), and some aphids—that mediate intracolonial communication, coordinate collective behaviors, and regulate caste differentiation, reproduction, and colony defense. These semiochemicals include trail pheromones, alarm pheromones, queen substances, and primer pheromones that physiologically alter receivers. Social insect pheromones often function as multicomponent blends with synergistic or redundant effects, and their production is frequently caste-specific and context-dependent.

Etymology

From Greek pherein (to carry) + hormon (stimulating), with 'social insect' denoting eusocial species with cooperative brood care, overlapping generations, and reproductive division of labor.

Example

In the fire ant Solenopsis invicta, workers deposit trail pheromones from the Dufour's gland to recruit nestmates to food sources, while queen-produced primer pheromones suppress ovarian development in workers, maintaining reproductive hierarchy without physical coercion.

Synonyms

• colony pheromones
• eusocial semiochemicals

Related Terms

• trail pheromone
• alarm pheromone
• Queen substance
• primer pheromone
• releaser pheromone
• Dufour's gland
• mandibular gland
• Semiochemical
• caste determination
• Trophallaxis
• nestmate recognition

Usage Notes

Distinguish from aggregation pheromones used by solitary species for mating or feeding; social insect pheromones specifically require a colony context with non-reproductive castes. 'Queen substance' historically referred to honey bee queen mandibular pheromone but is sometimes used more broadly. Primer versus releaser effects are functionally distinct: primer pheromones induce slow physiological changes (e.g., caste differentiation), while releaser pheromones trigger immediate behaviors (e.g., alarm response). Some social insect pheromones are propagated through trophallaxis, creating distributed colony-wide signals.