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 ...

In the Palaeogene, the continents drifted even closer to their present-day positions, and during the following Neogene Period the world was cooler and the effects of seasonality were more widely felt.