Honeybees live in social groups consisting of a queen, up to several hundred male drones, and thousands of infertile female workers. The drones mate with the queen only, and the workers protect the hive, forage, and feed and groom the queen. The health of the hive depends on the female workers performing these duties instead of reproducing.
What roles do pheromones play in maintaining a functional beehive?
Researchers observed that the queen produces a pheromone that attracts both drones and workers. They hypothesized that this pheromone inhibits ovarian development in the workers, making the workers infertile. To test this hypothesis, they exposed workers to a synthetic version of the queen pheromone and then recorded their 'ovary development score.' (Higher scores indicate more fully developed ovaries.) The results are shown in the graph here. Do these results support the researchers' hypothesis? Why or why not? (*** signifies P<0.001.)

Verified step by step guidance

1. Examine the graph provided, which shows the 'worker ovary development score' for two groups: Control and Queen pheromone. The y-axis represents the ovary development score, and the x-axis represents the two conditions tested.
2. Observe that the Control group has a higher ovary development score compared to the Queen pheromone group. This suggests that exposure to the queen pheromone results in lower ovary development in worker bees.
3. Note the presence of three asterisks (***), which indicates a statistically significant difference between the two groups with a P-value less than 0.001. This means the difference in ovary development scores is unlikely due to random chance.
4. Consider the hypothesis: the queen pheromone inhibits ovarian development in workers, making them infertile. The lower ovary development score in the Queen pheromone group supports this hypothesis, as it shows reduced ovarian development compared to the Control group.
5. Conclude that the results support the researchers' hypothesis that the queen pheromone plays a role in maintaining a functional beehive by inhibiting ovarian development in worker bees, thus ensuring they remain infertile and focus on their roles within the hive.

Key Concepts

Pheromones

Pheromones are chemical signals released by an organism that influence the behavior or physiology of others of the same species. In honeybees, the queen produces specific pheromones that play crucial roles in communication, mating, and regulating the reproductive functions of worker bees. These pheromones help maintain social structure and hive health by inhibiting the reproductive capabilities of workers, ensuring that they focus on their roles within the colony.

Ovarian Development in Honeybee Workers

In honeybee colonies, worker bees are typically infertile and do not develop fully functional ovaries, which is essential for maintaining the hive's social structure. The presence of the queen's pheromone is believed to inhibit ovarian development in workers, preventing them from reproducing. This inhibition is vital for the colony's organization, as it ensures that the queen remains the sole reproductive individual, allowing workers to dedicate their efforts to foraging and hive maintenance.

Experimental Design and Hypothesis Testing

Experimental design involves creating a structured approach to test hypotheses through controlled experiments. In this study, researchers exposed worker bees to a synthetic version of the queen's pheromone to assess its effect on ovarian development. The results, indicated by the 'ovary development score,' provide evidence to support or refute the hypothesis that the queen's pheromone inhibits ovarian development in workers, which is crucial for understanding the dynamics of bee reproduction and colony health.