Permian

280 Ma plate tectonic reconstruction

Selwyn Rock 2

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HercosestriaPair040111

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Permocupes sojanensis holotype and reconstruction

Weigeltisaurus reconstruction

EdaphosaurusDB

Permian

The Permian period is a significant unit of geological time that extends from about 298.9 million to 251.9 million years ago. It is the last period of the Paleozoic Era, following the Carboniferous Period and preceding the Triassic Period of the Mesozoic Era. The name "Permian" was introduced in 1841 by geologist Sir Roderick Murchison, after the city of Perm in Russia, where he studied a sequence of rocks representative of this period.

Overview

The Permian period is marked by the diversification of the early amniotes into the ancestral groups of many modern reptiles, amphibians, and mammals. This era witnessed the rise of the synapsids, including the therapsids, which are the direct ancestors of mammals. The Permian is also notable for the evolution of the first modern conifers, which would come to dominate forests in the subsequent Mesozoic era.

Climate during the Permian was generally dry and harsh in many areas, with large deserts spreading across the supercontinent Pangaea, which had formed late in the Carboniferous period. This climate contributed to the Permian's distinct flora and fauna, adapted to arid conditions.

Permian Extinction

The end of the Permian period is marked by the most severe mass extinction event in Earth's history, known as the Permian-Triassic extinction event or the Great Dying. Approximately 90% of all marine species and 70% of terrestrial vertebrate species became extinct. This event drastically reshaped life on Earth, paving the way for the rise of dinosaurs in the Mesozoic era. The causes of the Permian-Triassic extinction event are still debated, with hypotheses including massive volcanic eruptions, climate change, and ocean anoxia.

Geology

During the Permian, the world's landmasses were joined in the supercontinent Pangaea, surrounded by the global ocean Panthalassa. The tectonic activity associated with the formation of Pangaea led to significant geological events, including the uplift of mountain ranges and the formation of extensive basins and deserts. The Permian is also known for its distinctive red beds and evaporite deposits, indicative of the arid conditions prevalent during the period.

Permian Fossils

Fossils from the Permian period include a wide range of organisms, from plants and insects to large predators. Permian fossil sites around the world have provided critical evidence for understanding the evolution of life on Earth, particularly the transition from amphibian-dominated ecosystems to those dominated by reptiles and synapsids.

Legacy

The Permian period's legacy is seen in its significant impact on the evolution of life on Earth. The adaptations and diversifications that occurred during this time set the stage for the Mesozoic era, often called the "Age of Reptiles." The Permian's dramatic end, with the largest mass extinction event in Earth's history, serves as a profound reminder of the planet's dynamic and sometimes volatile nature.