Paleozoic

The Paleozoic Era (from Greek palaios = ancient, zoe = life, meaning "ancient life") is a major interval of geologic time that began approximately 541 million years ago and ended approximately 251.902 million years ago. It is the earliest of three geologic eras of the Phanerozoic Eon, the eon of visible life. The Paleozoic is divided into six periods, from oldest to youngest: Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian.

The Paleozoic Era is marked by a dramatic burst of evolutionary change known as the Cambrian Explosion, during which most major animal phyla appeared. It also saw the colonization of land by plants and animals, the evolution of fish, amphibians, and reptiles, and the development of complex ecosystems.

The era ended with the Permian-Triassic extinction event, also known as the "Great Dying," the Earth's most severe known extinction event, which wiped out approximately 96% of all marine species and 70% of terrestrial vertebrate species. This event drastically altered the course of life on Earth and paved the way for the rise of the dinosaurs in the subsequent Mesozoic Era.

The supercontinent of Pangaea assembled during the late Paleozoic, impacting climates and contributing to the end-Permian extinction. Fossil evidence from the Paleozoic provides crucial insights into the evolution of life and the geological history of our planet.