With spring comes the start of warmer temperatures, and early blossoms. However, spring also brings out the species that hibernate for the winter. One of these species includes the honeybee. The honeybee is one of most fascinating organisms because of the unique behaviors it displays. Honeybees have the ability to create honey with only two ingredients, pollen and nectar. Their ability to make honey though is not the only thing that makes them interesting to study. Honeybees have developed an organized system of dividing labor amongst each other in their societies. Unlike humans, honeybees do not need a degree or give an interview for jobs. This division of labor in honeybee colonies is affected by several factors such as hormones, brain structure, and worker nutrition.
How is labor divided in the colonies?
The division of labor in honeybees is a complicated system. That is why it is important to understand the different jobs that exist in colonies. The division of labor is based on colony development and growth. In humans, we have assigned leaders that help organize the division of labor. However, here is no authority figure that regulates the distribution of jobs in honeybee colonies. Instead, honeybees go through various job stages throughout their lifetime. At a young age honeybees start off as nest workers, and do not travel outside the nest at all. Most honeybees also start off as nurses, and attend to the brood, or offspring, of the colony. At later stages in their life, honeybees become foragers and are responsible for food gathering. They may also continue on to become defenders of the colonies as well.
What are the factors that affect the division of labor?
All these different jobs that the honeybees perform are affected by several factors. One of these factors is juvenile hormone, which is responsible for behavioral development, metamorphosis regulation, and reproduction. The amount of this hormone has an important role in determining how the labor is divided. When JH-III, a type of juvenile hormone, is injected into honeybee, there were several changes that the honeybee went through. As the honeybee aged, several physiological changes were observed in the bee, especially in foraging honeybees. Compared to other honeybees of the same age, the honeybees with the JH-III injection became foragers earlier. These changes may be due to the increase in the amount of juvenile hormone, especially because the field bees tend to have larger amounts of juvenile hormone.
Juvenile hormone is not the only hormone that effects division of labor in honeybees. The hormone insulin is a regulator of glucose in the blood, and is produced by the pancreas. Insulin is an important hormone that is associated with which jobs honeybees perform in the colonies. When insulin is injected into honeybees, the honeybees transformed from nurses to foragers in less than two days. This is much faster then the usual time it takes for honeybees to make this job transition. It is clear that insulin levels can cause shifts in the division of labor. An increase in the amount of insulin produces more foragers then what would be expected.
A second factor that has an effect on the types of jobs that honeybees take on is brain structure. The brains of the honeybees contain a variety of biogenic amines that can have an effect on the division of labor. Biogenic amines are small molecules that contain one or more amine groups. These biogenic amines include dopamine, octopamine, and serotonin, which are found in the brains of honeybees. There is a direct link between the change in the level of these biogenic and the jobs honeybees perform. When the honeybees are young, only two to three weeks, they are more likely to process food, and care for brood. Once in adulthood, the honeybee has higher levels of the biogenic amines and spends most of its time foraging. In these ways biogenic amines are considered an important factor that contributes to how labor is divided in honeybee colonies.
Another factor that effects the division of labor in honeybee colonies is worker nutrition. Most of the energy in honeybees is stored in abdominal lipid, or fat. Foragers tend to have lower lipid levels compared to nursing bees. Foragers also have lower lipid levels on the first day of foraging compared to other days. The foraging was initiated by a decline in lipid storage. Also, because nurses need to take care of the nest and young, they also need more energy. This helps to explain why nurses tend to have higher lipid levels then foragers. Nutrition is an important factor for dividing labor in colonies.
Why study this complicated system at all?
The division of labor in honeybee colonies is affected by all of these factors, which includes hormones, brain structure, and worker nutrition. Division of labor is important in organisms, such as the honeybee, because it provides a system of order to rather complicated behaviors. Honeybees are model organisms that allow us to extend the study of the division of labor to other organisms like humans. We can compare how the factors that influence honeybee division of labor, might affect the types of jobs we perform. The division of labor is used to divide jobs in a variety of ways in humans. It can be observed in families, politics, and religion, as well as many other places. Without the division of labor, it would be hard to imagine what our societies would look like. Could you imagine what our country would look like without organized government? It may be fun at first, but sooner or later there would be too much chaos. Therefore, it is important that we understand the importance of the division of labor, and how it brings structure and order to a complicated group of organisms.