phanero
Phanero is a term derived from the Greek words "phaneros," meaning visible or manifest, and "phainein," meaning to show. In the context of geology, phanero refers to the eon of the Earth's history that began approximately 541 million years ago and continues to the present day. This eon is characterized by the presence of abundant hard-shelled life forms, such as trilobites, mollusks, and eventually, dinosaurs and mammals. The Phanerozoic eon is further divided into three eras: the Paleozoic, Mesozoic, and Cenozoic. The term "phanero" is also used in other scientific contexts to describe phenomena that are visible or apparent, but this article focuses on its geological significance.