Dung Beatles Use Milky Way for Navigation: Study
In a surprising discovery, a new study shows that dung beetles navigate via the Milky Way, the first known species to do so in the animal kingdom.
The study is the result of researchers long suspecting the dung beetle of using the night sky to roll balls of animal sung in straight lines.
"This led us to suspect that the beetles exploit the starry sky for orientation - a feat that had, to our knowledge, never before been demonstrated in an insect," stated Marie Dacke, a biologist at Sweden's Lund University and lead author of the study.
The experiments show that despite their tiny brains and minimal computing power, the beetles can use the relatively dim light of the Milky Way for orientation - the first species proven to have this ability.
"They therefore have the potential to teach humans how to solve complex visual processing problems," says Wits University's Professor Marcus Byrne, who works on the "Visual Orientation in Dung-breeding Scarabs" project with colleagues from Pretoria University in South Africa and Lund University in Sweden.
After locating a fresh pile of feces, dung beetles will often collect and roll away a large piece of spherical dung. Last year, Dacke and her colleagues discovered the beetles climb on their dung balls and dance around in circles before taking off. This dance is not one of joy, however; the insects are checking out the sky to get their bearings.
"The dorsal (upper) parts of the dung beetles' eyes are specialized to be able to analyze the direction of light polarization - the direction that light vibrates in," Dacke told LiveScience. So when a beetle looks up, it's taking in the sun, the moon and the pattern of ambient polarized light. These celestial cues help the beetle avoid accidentally circling back to the poo pile, where other beetles may try to steal its food, Dacke said.