A study published in the journal Nature Communications unveiled that bats use polarization of the setting sun to adjust their internal magnetic compass mechanism.

Bats also use echolocation, but researchers said this strategy works only at distances of maximum 165 feet. The pattern of polarized light in the sky is strongest at dusk and dawn. Researchers tested their hypothesis as whether bats adjust their magnetic compass with the help from polarization pattern or not.

For the research, experiments on 70 female greater mouse-eared bats were carried out. The bats were taken from their home cave and were allowed to see the sky during the sunset, but from inside experimental boxes.

Researchers fitted the boxes with different light filters in order to manipulate the sun's polarization pattern. Bats were released from over 12 miles away and they tried to reach back home. The control group of bats was able to fly in the right direction.

But such was not the case with the experimental group that flew 90 degrees to the left or 90 degrees to the right. This led researchers to affirm that the polarization pattern of the sun acts as a trustworthy adjustment point for the bats in comparison to the sun's point in the sky. This is the reason that even when sky is full of clouds, polarization can provide accurate information.

Also, it has been found that the polarization patterns are visible for a long time even after the sun has set. Bats are important for ecosystem. "Unless we fully understand the behavior of the animal, we can't understand what they require from their environment, what we need to do to protect them within this environment", affirmed study researchers.