Book excerpt: From the moment we first began to contemplate the world, three questions have occupied our minds: Where do we come from?, What are we?, and Where are we going? Artists, religious thinkers, philosophers, and most recently scientists have all searched for answers. Here, the authors describe how scientists decipher human origin from the record encrypted in the DNA and protein molecules. After explaining the nature of descent and the methods available for studying genealogical relationships, they summarize the information revealed by the molecular archives. In doing so, they draw conclusions about our identity, our place in the living world, and our future.