What is a pheromone?

A pheromone is defined as a chemical substance that elicits a behavioral response in members of the same species. In the context of bees, pheromones play a crucial role in communication and the social structure of the hive. For example, queen bees release specific pheromones that signal their presence and maintain the colony’s social order. Worker bees also use pheromones to alert the hive about dangers, mark foraging routes, and coordinate activities.

The other options do not accurately describe pheromones. Though plant scents can attract bees, they are not considered pheromones, as they serve more as a part of the plant's reproductive strategy rather than a chemical communication tool among bees. Furthermore, while bees do gather food sources such as nectar and pollen, these substances are distinct from pheromones and do not elicit behavioral responses in the same way. Lastly, pheromones are not a defensive mechanism in themselves, although certain pheromones may trigger defensive behaviors among bees when a threat is perceived. Thus, identifying pheromones as chemical substances that influence behavior reinforces the understanding of their critical role in bee communication and colony dynamics.