Entomologists studying the behavior of bees have noted that honey bees seem to know when a hive is infected with fungi and they know which plant resins are able to treat the disease, and at times of threat the bees work hard to protect the hive.
A new research paper suggests that when a bee colony becomes infected with a pathogenic fungus, the bees "self-medicate" by bringing back large quantities of anti-fungal plant resins to the hive. The resin help the colony to fight the infection.
The research has been carried out at the North Carolina State University's "bee lab", under a team led by Dr. Michael Simone-Finstrom. The paper has been published in the Public Library of Science.
In the paper, the scientists argue that the worker bees are willing to burn more energy by collecting the resins in addition to the normal quantities of pollen. As the resin is of benefit, the bees appear to have carried out some kind of 'cost-benefit' analysis.
In a special report from the University, it was noted that when the bees bring the resin (termed propolis) back they mix it with wax and coat the inside of their hives, making something akin to an anti-fungal paint. When the risk of a fungal threat is high, the bees bring back far greater quantities of plant resin.
The study also showed that the bees remove any infected larvae from the hive to prevent the fungal spores from spreading. The bees thus displayed a form of altruistic behavior, to protect the majority population in the hive.
The reference for the paper is:
Michael D. Simone-Finstrom and Marla Spivak. Increased Resin Collection after Parasite Challenge: A Case of Self-Medication in Honey Bees? PLoS ONE, 2012; 7 (3)