In this episode, I will be speaking about one of the greatest mysteries of biology, how we and every other living thing take geometric shape. Modern scientists mostly understand how we have blue eyes or grow to six foot one, or even how cells divide. What is far more elusive is the manner by which these cells know exactly where to place themselves in each stage of the building process, so that an arm becomes an arm rather than a leg, as well as the very  mechanism which gets these cells to organize and assemble themselves together into something resembling a three-dimensional human form.