Who survived the cretaceous time period?

During the Cretaceous period, which ended about 66 million years ago, many species faced extinction, including the non-avian dinosaurs. However, some groups survived, notably small theropods, which eventually evolved into modern birds. Additionally, mammals, reptiles like crocodiles, and various marine life forms such as fish and some invertebrates also persisted through this mass extinction event. These survivors played a crucial role in the subsequent evolution of life on Earth.