Before revision: In the 20th century, Karl von Frisch showed that honey bees can navigate by the sun\Sun , by the polarization pattern of the blue sky, and by the earth 's magnetic field; of these, they rely on the sun when possible.
After revision: In the 20th century, Karl von Frisch showed that honey bees can navigate by the s\Sun , by the polarization pattern of the blue sky, and by the Earth 's magnetic field; of these, they rely on the Sun when possible.