Learn more about a time period marked by an intense burst of evolution. 3 min read The Cambrian period, part of the Paleozoic era, produced the most intense burst of evolution ever known.

Learn about the time period that took place 65 to 23 million years ago. 3 min read At the dawn of the Paleogene—the beginning of the Cenozoic era—dinosaurs, pterosaurs, and giant marine ...