Bruce Alberts received his PhD from Harvard University and is the Chancellor's Leadership Chair in Biochemistry and Biophysics for Science and Education, University of California, San Francisco. He was the editor in chief of Science magazine from 2008 until 2013, and for 12 years he served as president of the U.S. National Academy of Sciences (1993-2005). Karen Hopkin received her PhD in biochemistry from the Albert Einstein College of Medicine and is a science writer in Somerville, Massachusetts. She is a regular columnist for The Scientist and a contributor to Scientific American 's daily podcast, "60-Second Science." Alexander Johnson received his PhD from Harvard University and is Professor of Microbiology and Immunology and Director of the Biochemistry, Cell Biology, Genetics, and Developmental Biology Graduate Program at the University of California, San Francisco.