What is the Phanerozoic Eon?
The Phanerozoic Eon is a geologic time division that extends from roughly 542 million years ago until the present. The name derives from Greek and means “revealed life,” because the Phanerozoic Eon is defined as the period of time during which hard-shelled macroscopic multicellular organisms, beginning with trilobites, archaeocyatha, and a few other early genera, existed. The Phanerozoic is the most recent of four geologic eons that divide up time on Earth since its formation: the Hadean, Archean, Proterozoic, and Phenerozoic. Although it only encompasses about 10% of the Earth’s total age, it is throughout the Phanerozoic Eon that the life with which we are familiar evolved and covered the planet. Prior to the Phanerozoic, the only living things were numerous unicellular organisms and some blob-like and disc-like early multicellular organisms called the Ediacaran biota. The Phanerozoic is divided into three eras: the Paleozoic, Mesozoic, and Cenozoic. In Greek, these terms mean: early
The Phanerozoic Eon is a geologic time division that extends from roughly 542 million years ago until the present. The name derives from Greek and means “revealed life,†because the Phanerozoic Eon is defined as the period of time during which hard-shelled macroscopic multicellular organisms, beginning with trilobites, archaeocyatha, and a few other early genera, existed. The Phanerozoic is the most recent of four geologic eons that divide up time on Earth since its formation: the Hadean, Archean, Proterozoic, and Phenerozoic. Although it only encompasses about 10% of the Earth’s total age, it is throughout the Phanerozoic Eon that the life with which we are familiar evolved and covered the planet. Prior to the Phanerozoic, the only living things were numerous unicellular organisms and some blob-like and disc-like early multicellular organisms called the Ediacaran biota. The Phanerozoic is divided into three eras: the Paleozoic, Mesozoic, and Cenozoic. In Greek, these terms mean:
