We used to think of fossils as being composed of nothing but rock and minerals, but we were wrong. Today, scientists and the science of ancient biomolecules—pigments, proteins, and DNA that once functioned in living, but now extinct, organisms—are opening a new window onto the evolution of life on Earth. Dale E. Greenwalt, a research associate at the National Museum of Natural History, is your guide to these astonishing breakthroughs.
