Queen Succession in Honeybees

http://greensmiths.com/images/honey.7.jpg (Oct. 9, 2007)

 

Ontogeny (Development)

How does a bee become a queen?

A bee becomes a queen bee as opposed to a female worker bee through development. In genetic terms queens and female worker bees do not differ, both have the same type and amount of genetic information. This means that differences between queen honeybees and worker bees arise through diffrent environmental conditions in the course of development. Differential gene expression is caused by these diffrent environmental conditions and accounts for the diffrences between groups, this phenomena is called polyphenism (Evans and Wheeler 1999).

What do you mean different environmental conditions?

In the first two days of life all larvae are feed royal jelly, a nutrient rich food that is in part produced from mandibular secretions of adult worker bees (Evans and Wheeler 1999). From this differential development queen larvae develop much faster and begin to show different hormone production as compared to worker larvae. It is commonly stated that by the fifth instar, or stage of development, queens have clearly developed reproductive organs while the worker bees do not. This statement is mostly true but articles by Perk et al. (2004) suggest that up to four percent of workers develop functional ovaries (for more on this see adaptive value). The development of queens is much faster than that of workers due to lower levels of juvenile hormone present in the insect, this hormone controls general development mainly through suppressing development (Evans and Wheeler 1999). It is rather surprising that queen development is marked not by the activation of genes that workers lack rather by the suppression of up to five genes active in normal worker bees.

http://www.answers.com/topic/queen-bee-2

The above image shows a tiny queen larves floating in royal jelly, normally the queen larvea would be self contained but the cell was opened to take this photo.


Where does queen development takes place and how do they communicate with the colony?

Queens develop in caped wax cells that are relatively isolated from other developing larvae. Developing queens communicate with the rest of the colony and with one another through auditory cues such as piping (click on the link to hear queen piping, there is lots of buzzing in the background but you will know the shrill piping) as well as through chemical signals. In a study by Pettis et al. (2004) the compounds that collect in the wax of the queen cell are different from the chemicals that are normally present in cell wax. This trend may suggest that the nurse bees of a developing queen may control the chemicals she is exposed to and thus show communication between queen and colony. The vertically oreiented queen cells pictured below are clearly very distinctive form the normal developing bees on the right.

hive

Caped Queen cells (http://www.answers.com/topic/queen-bee-2) as compared to developing worker cells (image on right from http://www.dkimages.com/)

images from: http://www.answers.com/topic/queen-bee-2

The above image shows the vertically developing queen pupae, normally such a queen would be fully enclosed here the cell was artifically opened.


How does Queen development effect queen succession behavior?

Queen development is intimately tied with queen succession. In natural settings the queen that develops the fastest has the best odds in winning queen-queen duels and thus breed in the colony (Tarpy, Hatch, and Fletcher 2000). It appears that queens who emerge first in a queen-less colony have advantages over newer queens because they can begin producing hormones to attract workers to them as well as to suppress other queen's development. Novel queens will, if allowed by the workers, kill other developing queens by cutting a hole in the side of their cell and stinging the larvae. Thus queens that can develop the fastest are the one's most likelt to suceed in a colony.