A colony keeps its queen or begins rearing a replacement. Which statements explain how workers assess their queen?
More than one answer is correct.
- Workers respond to a combination of queen signals, information from young brood and conditions within the colony.
- The amount of queen mandibular pheromone alone is enough to assess the queen’s reproductive ability fully.
- Contact with the queen and between workers helps transmit queen signals throughout the colony.
- Workers have been shown to count the eggs laid and thereby detect every interruption of egg laying immediately.
- Young brood can influence the colony’s response even when the queen is still present.
- There is a proven pheromone threshold, valid for all colonies, below which the queen is replaced.
Show the answer
Correct answers: 1, 3 and 5.
Why?
- 1 — True. The workers’ response depends on several sources of information. These include the queen’s chemical signals, signals from young brood, and the colony’s resources, season and condition. Their effects change over time.
- 2 — False. Queen mandibular pheromone, or QMP, is only one part of chemical communication. Other substances contribute to the queen’s influence. The mandibular compounds studied have not always allowed researchers to distinguish normally mated queens from drone-laying queens.
- 3 — True. Queen substances first pass to workers in her retinue and then spread through further contacts within the colony. Wax also acts as a carrier and reservoir. This is not simply a scent distributed uniformly throughout the hive.
- 4 — False. The studies reviewed in the article demonstrate neither egg counting nor direct detection of every interruption of egg laying. Whether workers recognise an interruption independently of brood signals and other changes remains an open question.
- 5 — True. In one experiment, removing eggs and young larvae led six out of nine colonies to begin queen rearing despite the presence of a healthy queen, compared with one out of nine control colonies. This demonstrates an influence of young brood, not an inevitable replacement of the queen.
- 6 — False. No universal, measurable threshold for queen replacement has been demonstrated. The dynamic model presented in the article helps explain possible interactions, but does not reliably predict whether a queen will be replaced.
What you should understand
“Assess” here means that workers adjust their behaviour in response to biological information. It does not imply conscious judgement or a complete examination of fertility. The colony also changes the information it receives: it feeds the queen, rears the brood and distributes chemical signals. This creates feedback between the queen, brood and workers.
Key takeaway
Neither a single pheromone nor the absence of eggs alone explains why a colony keeps or replaces its queen. Consider the queen, young brood, resources and sequence of events together. The start of queen rearing does not necessarily mean that replacement will follow.
Further reading
► How do bees assess their queen?