Extrafloral nectaries are specialized structures found on the surfaces of plants that produce nectar outside of the flowers. This nectar serves as a food source for predators and parasites of herbivores, acting as an indirect defense mechanism for the plant. Extrafloral nectaries are found in a wide variety of plant species and are thought to have evolved as a way to attract beneficial insects that can help protect the plant from herbivores. Research in this area focuses on understanding the ecological significance of extrafloral nectaries, their role in plant-insect interactions, and the diversity of their form and function across different plant species.