"Biology: A Guide to the Natural World" remains the only book written and illustrated from the ground up for those with little knowledge of biology. The Third Edition retains its best features rich, full-color art, an accessible writing style, and a full complement of digital resources while substantially updating the content throughout to emphasize the relevancy of biology to readers' lives. A seven-part organization covers essential parts: atoms, molecules, and cells; energy and its transformation; how life goes on: genetics; life's organizing principle: evolution and the diversity of life; a bounty that feeds us all: plants; what makes the organism tick? animal anatomy and physiology; and the living world as a whole: ecology and behavior. For the promotion of biological literacy to make individuals aware that they need it to participate in the workforce, make everyday decisions, and make informed choices at the ballot box.