The term "Phanerozoic" refers to a major eon in Earth's history that extends from approximately 541 million years ago until the present day. It is characterized by the abundance of multicellular life forms, which makes it the most recent and relevant eon for the study of biodiversity. The name "Phanerozoic" is formed by combining two Greek words, "phaneros" meaning visible and "zoikos" meaning life.
This eon is divided into three distinct eras: the Paleozoic, the Mesozoic, and the Cenozoic. Each era encompasses different geological periods, and during these periods, various significant events occurred, such as the rise and fall of different species, evolution of new life forms, and major geological changes.
The Phanerozoic eon is crucial in understanding the geologic, biological, and climatic evolution of the Earth. It witnessed the emergence of numerous iconic life forms, including fishes, plants, insects, reptiles, dinosaurs, mammals, and eventually humans. It also experienced several mass extinction events, such as the Permian-Triassic extinction event, which wiped out approximately 96% of marine species.
Phanerozoic rocks are extensively studied to understand the history of life on Earth and to reconstruct ancient ecosystems. Fossils found in these rocks provide crucial information about the evolution, behavior, and interrelationships of past organisms. This eon has been a dynamic period, marked by constant changes in biodiversity, climate, and landscapes, laying the foundation for the diverse ecosystems and the complex web of life that exists today.
