The term "Permian" refers to a geological period that lasted from about 299 to 252 million years ago. It is the last period of the Paleozoic Era and is known for significant geological and biological changes, including the formation of the supercontinent Pangaea. The Permian period ended with the largest mass extinction in Earth's history, which wiped out approximately 90% of marine species and 70% of terrestrial vertebrates. During the Permian, diverse ecosystems thrived, including vast deserts and lush forests. The period saw the evolution of early reptiles and the dominance of ammonites and trilobites in the oceans. The climate varied from arid to humid, influencing the types of plants and animals that existed at the time.