Sensitivity of Ants to Polarized Light

Abstract

THE work of von Frisch¹ has shown that the honeybee is sensitive to the plane, and possibly to the degree, of polarization of light. Von Frisch himself suggests that some old observations made by Santschi² on the homing of ants could be interpreted as suggesting a similar sensitivity. Santschi's experiments, done during summer evenings in the Tunisian desert, showed that some individuals (notably of the genera Cataglyphis and Monomorium), when returning to their nests, were able to continue in the correct direction although surrounded by a tubular screen of black board. This screen, 50 cm. in diameter and 25 cm. high, restricted the field of view to an arc of sky subtending an angle of 90° at the ant: the sun was excluded by a further screen when necessary. When a flat, horizontal screen was substituted for the tube, the orientation of the ants was disturbed. These experiments have remained almost unnoticed and, unless one accepts Santschi's own theory of sidereal orientation, apparently uninterpreted.