Hi friends, Antennas help butterflies in the senses of smell and feel but I was surprised to learn that in the Monarch (Danaus plexippus), and in possibly many others, antennas contain a biological sun-compass (akin to a circadian rhythm) with the help of which they can detect the angle of incident polarised light falling on the antenna and thus deduce the position of the Sun in the sky!
Recent research by American scientists that they corelate this information with the time of day as per the biological clock of circadiian rhtyhm in their brains and determine which is South even though the Sun keeps changing its position in the sky! They then migrate! Imagine! Its like being told that the tip of your nose can point you Southwards based on how the sunlight falls on it? I wonder which Indian butterflies use this as a migration aid? The Indian Danaids? What other mysteries does biology hold for us? Read more at:- http://thebutterflydiaries.wordpress.com/2009/11/17/antennas-gps/ <http://thebutterflydiaries.wordpress.com/2009/11/17/antennas-gps/> -- Enjoy
