Meeting Abstract
Over 150 different species of animals have been shown to use the Earth’s magnetic field for orientation and navigation; however, the basic mechanisms underlying magnetoreception are not yet well understood. The fruit fly Drosophila melanogaster is an attractive organism for studying magnetoreception because it is a model organism for understanding the genetic basis of behavior and could therefore lead to insights regarding the cellular mechanisms of magnetoreception. Several studies suggest that Drosophila can detect magnetic fields, but the behavioral responses of fruit flies to magnetic fields vary from study to study. In an effort to confirm whether or not Drosophila have an innate directional preference, we designed a sequential Y-maze so that in each experimental trial Drosophila make multiple directional choices based on the Earth’s ambient magnetic field. The directional preferences of male and female flies were analyzed separately because one previously published study found that male flies orient to magnetic fields, but female flies do not. We found that the orientation of neither male nor female flies was different from a random distribution (p > 0.9). Our results indicate that adult Drosophila do not have an innate magnetic directional preference; however, our results do not eliminate the possibility that Drosophila can detect magnetic fields. The absence of a strong innate directional preference in Drosophila may be the primary reason that significant progress in identifying a magnetoreceptor in Drosophila has not been made. We have begun a long-term selective breeding experiment in an effort to develop a line of strongly magnetotaxic Drosophila with a robust, predictable behavior that can be used to tease apart the underlying mechanisms of magnetoreception.
