In the previous article, we discussed the Carboniferous period, ending with a minor extinction event. Now let’s discuss the last period of the Paleozoic Era- the Permian.
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Diversification of Amniotes- First Mammals
The first major change during the Permian period comes within animals. Starting with amphibians, the group of amniotes starts to develop. By the end of the period Archosauriformes- ancestors of dinosaurs and pterosaurs appeared. Cynodonts, that will evolve into first mammals, also appeared. The entire group of synapsids, which today includes mammals and their ancestor, flourished during that time. By the end of the period, they started being dominant vertebrates. Within the terrestrial fauna herbivores and carnivores evolved. There were mostly lizard-like animals, with skulls without opening near the temples. They were soon to evolve into dinosaurs and later on- to modern reptiles.

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Development of Insects During the Permian Period
The first arthropods were probably trilobite-like. However, the evolution led to organisms adapted to conditions on Earth. Insects’ most special features include the quite developed digestive system and wings. Today, they are the most numerous animal group on Earth, making the rest of the ecosystems dependent on them. First insects developed in the Carboniferous. The Permian started with cockroaches. They were way less developed than the forms we know today, however, wings and exoskeleton make them one of the most successful organisms of the period. Another predator group was the first dragonflies. Their larvae develop in the water, whereas adult forms are aerial. However, they were quite different from the forms we know today. Some of them had wings over 70 cm long!
Changes in Earth
Due to the fact, that sea levels were quite low during the period, not much happened in the marine waters. During the Permian period, a supercontinent Pangea collected most of the land. A lot of coastal space disappeared, which caused the extinction of some species. Pangea spread through the middle of the Earth, from the North to the South Pole. One major ocean took most of the water, however, there was also a smaller one between today’s Asia and Africa. The name ‘supercontinent’ may suggest stability, however, Pangea constantly changed. Landmasses moved to cause shrinking and creating new oceans. Climate was quite diverse, due to the fact, that Pangea spread through all latitudes. Generally, temperatures varied during the Permian period, with the tendency to drying. That caused the appearance of deserts in the middle of the continent.

The End of the Permian Period
The life development of the Permian period sounds fabulous, however, it ends quite tragically. Scientists are not sure what caused the so-called ‘Great Dying’. It might have been a huge volcanic eruption or some changes in the carbon cycle in nature. Whatever it was, the acidity of waters and lands rose fast near the end of the period. The Permian-Triassic extinction event was the biggest mass extinction in our planet’s history. The marine life suffered most, due to the lack of coastal waters and the dropping of sea levels. First jaw fishes were eliminated forever, the same happened to trilobites. However, it was the marine life, which recovered first after the end. The terrestrial organisms we talked about, like first mammals, reptiles, and insects, also went extinct. Totally, 96% of species extinct during the event. When life was recovering, many new ecological niches caused the development of reptiles.
The Permian Period Evidence
The Permian period is the last one with trilobites and many other fossils. Some of the most significant pieces of evidence include bones enabling reconstruction of Cynodonts. There are also many reptiles and preserved trace fossils of dragonflies and cockroaches. Despite the fossils, there are also many interesting studies of the Great Dying. A study conducted by a team from Utah State University and the University of Nevada-Reno, published in June 2019, suggested new evidence for the cause of the Permian mass extinction. The discovery of boundary between periods in Utah led to the conclusion that the coal from the volcanic eruption caused the extinction. Moreover, global warming led to the acidity of oceans and marine organisms best adapted to new conditions. It is also important to highlight, that the study of past events may help scientists in forecasting changes on Earth today.

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Read the previous in the series: The Carboniferous period.
Author’s Message
I hope that the article helped you learn about the Permian article. If you enjoyed it, please share it with family and friends. In the next article, we will start the new era- Mesozoic. Until then, if you have any questions, feel free to contact me. You can find my email address in the team’s section of the page.
[…] Read the previous in the series: The Permian Period. […]