(Updated)
Understanding the life cycle of the different castes of honey bees can provide valuable insight to a beekeeper.
Whether a queen, drone, or worker – the honey bee goes through the same cycle illustrated below. Starting as an egg to a larva to a pupa and finally emerging as an adult honey bee.
The food consumed varies (as the case with the queen – being fed only royal jelly during all stages of development and life). Still, a significant difference in the days that each caste stays in each stage of development. Below are the average times in days within each stage.
| Stages/Castes | Queen | Worker | Drone |
| Egg | 3 | 3 | 3 |
| Larva | 5.5 | 6 | 7 |
| Pupa | 7.5 | 12 | 14 |
| Total | 16 | 21 | 24 |
When you hear the word “Brood”, this defines all stages of development, collectively referred to as brood.
Each caste starts its existence as an egg.
The queen lays a single egg in each brood cell. The size of the cell will alert the queen as to what type of egg to lay, a smaller cell for a fertilized egg and a larger cell for an unfertilized egg respectively.
Honey bee’s genetics are based on Haplo-Diploidy Sex Determination.
The females (queen and worker) have two pairs of chromosomes(32); they get one pair from their mother (the queen), and one pair from their father (the drone).
The drone has only one pair of chromosomes (16); they get all their genes from their mother. This is because the drone comes from an unfertilized egg from its mother.
The worker and queen are genetically similar, only differing in their fathers but tied to their only mother; they come from a fertilized egg. Since a queen mates with many fathers – this creates a genetically diverse colony; each honey bee has the strengths and weaknesses of its different fathers and is tied genetically to its mother.
Since queens and workers both come from a fertilized egg, they start to diverge around day 6, when the larvae designated to be a worker will begin to be fed a different diet, a rationed portion of pollen/nectar termed ‘bee bread”.
What’s truly fascinating about this is that ALL brood prior to around day 6 are queens since these brood are fed royal jelly exclusively. Only after this time, when they switch over to another diet, do they start their biological process of becoming worker bees.
What is really interesting is what happens with a laying worker colony. Since a laying worker does not mate, it can only produce drones that are unfertilized eggs. Like the queen, that means that her son,the drone, is 100% related to her, and she is 50% related to him (due to passing on one pair of her chromosomes (16 out of 32).
So we see that each caste starts as an egg. After the egg melds into a larva (they do not hatch since there is no membrane), the queen continues to be fed royal jelly, and the drone and worker are provided bee bread.
Once they pass all the stages of development, they emerge to start their work within the colony.
We will in future articles discuss these processes in greater detail – but an overview of the honey bee cycle provides terrific insight into the colony as a whole. The brood cycle is a central part of the honey bee life. The colony is replaced every 6-8 weeks (worker and drone approximate life cycles) as the queen will outlive her children for many, many generations of colony cycles. The healthy brood cycles are key to keeping the colony alive and thriving.
ARTICLE REFERENCES:
- Honey Bee Biology Pages 53-56