How Honey Bees Navigate

Rebecca Reilly
Period G
5/18/17

How Honeybees Navigate 

Scientists believe that bess can become the model organism for studying magnetoreception.

Navigation

According to a team of physicists and biologists in Canada, honey bees sense magnetic fields using a magnetic structure in their abdomens. By carrying out a series of physics and behavioral experiments on insects, it showed that the sensory ability that the bees have can be disrupted using a strong magnet. The underlying mechanisms of magnetoreception is what make this navigation possible. Magnetoreception is s a sense which allows an organism to detect a magnetic field to perceive direction, altitude or location. Bees contain magentite from a ferromagnetic oxide of iron that is also found in some types of rock. Honey bees respond to local magnetic fields in a way that is consistent with magnetite-based magnetoreception. This proves that a ferromagnetic material containing magnetite exists in the abdomen of honey bees. This material can be magnetized by using a strong permanent magnet that magnetizing the abdomen of a live honey bee disrupts its ability to navigate using local magnetic fields.

Evidence

The researchers first dissected a number of honey bees. They separated the bodies into different parts representing the anatomy of the bee: the abdomen, the thorax, and the head before crushing the body parts into pellets. Then they used a Superconducting Quantum Interference Device (SQUID) to measure the magnetization of each pellet after it was exposed to a magnetic field. The data showed that there was no evidence of ferromagnetism in pellets made from the thoraces and heads, but there was clear evidence of ferromagnetism for the abdomen sample. After, a strong permanent magnet was used to expose live honey bees to a magnetic field of 2.2 kOe, which is several thousand times stronger than the Earth's magnetic field, for about 5 seconds. Further results with the SQUID revealed that pellets made from the abdomen of these bees were more strongly magnetized than pellets made from bees that had not been exposed to a magnetic field.

 

Magnetization affects the ability of bees when they navigate a food source. In order to prove this, scientists trained a group of bees to locate sugar in an environment where electrical coils create a magnetic field. Half of the trained bess were magnetized and the other half of the train bees were not. The two different groups of bees were then compared to each other. Scientists found out that the magnetized bees were unable to find the sugar. This means that their magnetoreceptors had been disrupted by the magnetization process. Even though the study does not provide direct information about the biological mechanisms involved in magnetoreception, one of the scientist, Hayden, says: "The fact that we were able to disrupt the magnetic sense may well help to open doors or provide traction for future lines of inquiry.” Hayden also adds that him and the rest of the scientists hope to eventually answer questions “such as the potential impact of industrial electromagnetic noise on the bees' magnetoreceptor and their overall well-being". Hayden believes that future experiments could investigate the microstructue  of the magnetoreceptor.