During the Oligocene epoch about 33.9 to 23 million years ago, most mammals remained small, but one giant, Paraceratherium, ...

3 min read At the dawn of the Paleogene—the beginning of the Cenozoic era—dinosaurs ... whales in the mid- to late Paleogene. The huge animals evolved from land mammals that took to the ...

These strange animals are ... roots can be traced back approximately 64 million years to the early Cenozoic era. Native to the Amazon rainforest, this bird is notable for its distinctive ...

Understanding ancient ocean temperatures—particularly from the Cenozoic era (the past 66 million years), in which Earth experienced dramatic climate shifts—helps scientists reveal more about ...