The puzzle seems impossible: take a three-billion-letter code and predict what happens if you swap a single letter. The code we’re talking about—the human genome—stores most of its instructions in ...

We’re celebrating 180 years of Scientific American. Explore our legacy of discovery and look ahead to the future. In 1957, just four years after Francis Crick and other scientists solved the riddle of ...

_Tyrannosaurus rex_ was a relentless predator who lived during the Cretaceous Period more than 65 million years ago. Roger Harris/Science Photo Library via Getty Images DNA – which stands for ...