Other animals are known to polarize light, but scientists are aware of the anatomical structures that make it possible. For instance, bees have specially adapted photo-receptors in their eyes, and birds, fish, amphibians and reptiles all have cone cell structures in their eyes which may help them to detect polarization. Scientists do not know the structure that the bats are using.
Polarization patterns depend on where the sun is in the sky. They are clearest in a strip across the sky 90° from the position of the sun at sunset or sunrise. But animals can still see the patterns long after sunset. This means they can orient themselves even when they can't see the sun, including when it's cloudy. Scientists have even shown that dung beetles use the polarization pattern of moonlight for orientation. A hugely diverse range of creatures - including bees, anchovies, birds, reptiles and amphibians - use the patterns as a compass to work out which way is north, south, east and west.
Read more (Journal reference): Stefan Greif, Ivailo Borissov, Yossi Yovel, Richard A. Holland. A functional role of the sky’s polarization pattern for orientation in the greater mouse-eared bat. Nature Communications, 2014; 5 DOI: 10.1038/ncomms5488
Story via ScienceDaily.com