The new discovery was made by scientists researching the brains of tiny worms at the University of Texas at Austin. The research sheds light on a mystery that has persevered for decades: how do the internal compasses of migrating animals function? Until now, we knew only that they used the magnetic field to guide themselves.
While studying the worm, C. elegans, the scientists discovered a microscopic structure attached to the end of a neuron. Shaped like a TV antenna, the worms use it to sense Earth’s magnetic field and find their way as they tunnel underground.
They also noted that the hungrier the worms became when introduced to gelatin-filled tubes, the more likely they were to venture down farther–possibly expanding their search for vital nutrients.
When worms from far-away environments such as Hawaii, Australia or England were placed in similar tubes, not all of them reacted the same way. Instead, they moved at an angle that would have been down if they were still in their natural habitat–almost as if they were dizzy or confused so far away from home.
Could other animals use the same kind of neuron antenna to sense Earth’s magnetic field?
The researchers believe that the same microscopic structure the worms use to navigate will likely be found in other animals with similar tendencies.
Assistant professor of neuroscience in the College of Natural Sciences Jon Pierce-Shomomura commented on the findings: “Chances are that the same molecules will be used by cuter animals like butterflies and birds. This gives us a first foothold in understanding magnetosensation in other animals.”
The discovery was mostly an accident. The scientists initially set out using the worms to conduct research on Alzheimer’s disease and addiction. Along the way, they found that C. elegans could detect humidity, which inspired them to find out what else the odd creatures could sense.
The research was published in the online journal eLife on Wednesday.