About the Author
Larry Gonick has been creating comics that explain math, history, science, and other big subjects for more than forty years. He has been a calculus instructor at Harvard (where he earned his BA and MA in mathematics) and a Knight Science Journalism Fellow at MIT, and he is currently staff cartoonist for Muse magazine. He lives in San Francisco, California.
Craig Criddle is a professor of environmental engineering and science at Stanford University and has written numerous scientific papers.