By Vidya Rajan, Columnist, The Times The study of animal form and function is both illuminating and fascinating, panning from simple to complex forms. The morphing started 750-odd million years ago. At this time, the Earth was not young by any means! It was already about 3.5 billion years old (80% of its age today, which is about 4.3 billion years old) and populated by cyanobacterial mats, and single-celled...