Plain and simple answers to more than 1,250 questions about the formulas, history, major personalities, latest developments, milestones, evolution and organisms that make up the world of biology. This major new reference work is a go-to guide for students and the more learned, and is helpfully laid out with numerous black-and-white illustrations. The authors are both scientists and have previously written The Handy Math Answer Book, The Handy Dinosaur Answer Book and The Handy Ocean Answer Book (all Visible ink).