Piggyback riding is popularly seen among animals and are doing this jolly ride from time unknown.  The researches in Austria and Italy discovered fossils of marine animals that seem to have been riding piggyback on other animals 425 million years ago.  As we smile at the mischievous behaviour of these animals we also need to understand that this is an age old behaviour.  This surprisingly common behaviour found among animals and birds may have many reasons like the tired bird taking rest or the lazy ...