17 April 2023

What is the Paleozoic Era? – Learn about the most important events of the Paleozoic Era

By Donald

It is known as the primary era or the era of invertebrates, as it is the first phase of the Phanerozoic Eon. It began 542 million years ago to the present, that is, it lasted 290 million years and after it the Mesozoic and Cenozoic eras occurred. From this moment on, life began to take various forms where organisms developed and thus moved from the oceans to the land.

What does the Paleozoic Era mean?

The term paleozoic comes from the Greek palaio (old) and zoe (life), and means ancient life. So this name is assigned to it because the most primitive forms of existence are created in it, as is the case of beings with shells or exoskeletons. In addition, in this era there were very important changes on earth, after the rupture of the supercontinent called Pannotia and the start of a new one.

On the other hand, this era was very rich from a biological point of view, since the plants that originated spread and evolved, in addition, there is a great transition between vertebrate and invertebrate animals. From this moment, the seas filled with life and they moved to the land, spreading throughout the planet and creating new habitats.

It should be noted that in this period there was an increase in the warmth of the planet, which produced a stability that coincides with the propagation of oxygen throughout the atmosphere. This happened after a cold wave in which gigantic extensions of the Phanerozoic Eon were produced.

As this era has been going on for a long time, it is traditionally divided into six periods, each one from different eras as follows:

  • Cambrian period (541 ma—485 ma): In this phase, life occurs in the seas and oceans. With the great Cambrian explosion, different living beings began to emerge on earth, also, thanks to the fact that the seas were not deep, large invertebrates and multicellular creatures with an exoskeleton more complex than bacteria and protists originated.
  • Ordovician period (485 ma – 444 ma): This period was characterized by the appearance of lichens and bryophytes and thanks to the absence of oxygen in the atmosphere, life on earth became very difficult. Likewise, plants and fungi began to be born on the earth’s surface and the continents began to get closer again. There was also what was the greatest extinction of living beings thanks to large formations of glaciers.
  • Silurian period (444 ma – 416 ma): It is characterized by the appearance of jawed fish, freshwater fish and other animals such as spiders and centipedes. In addition, the first plants with a vascular system arose and oxygen levels reached those of today. At the end of this period there was also another extinction event known as the Lau event, due to the decline in sea levels.
  • Devonian Period (416 ma – 359 ma): the rains and the warm climate predominated in this period, the fish adapted to fresh and salt waters, in addition, large coral reefs arise. Seed plants spread over the land and this favors the expansion of vegetation where amphibians are first seen as terrestrial arthropods.
  • Carboniferous period (359 ma – 299 ma): its main feature was the large number of amphibians and reptiles that existed on earth. As for the climate, it was very diverse, since the pole areas were in glaciation and the equator areas had hot and humid climates, which helped the formation of swamp environments.
  • Permian Period (299 ma – 251 ma): in this paleozoic stage the first turtles, mammals and primitive dinosaurs were seen. Lizard-like reptiles also arose and these were land animals, although there were semi-aquatic ones. Finally there were great earthquakes that caused the continents to sprout from the seas.

What are the characteristics of the Paleozoic Era?

This first phase through which the earth passed has many distinctive facts that helped the evolution of the planet. Some of the most important features in this era were:

  • The plants and animals managed to reach the land, leaving their life in the seas.
  • Many animals began to have skeleton and shell.
  • The continents were joined into a single mass called Pangea.
  • the first emerged trees and ferns.
  • Oxygen was regulated in the atmosphere to the same as it is today.
  • Insects, amphibians, reptiles and some mammals appear, which they ate plants or other organisms.
  • With the melting of the glaciers, the continents were invaded by the waters.

What was formed in the Paleozoic era?

In this era there were important variations that contributed to the advancement of the planet and the eras that would later occur. In principle, climatic changes that arose, since when the glaciation ended, a warming process began, where the levels of carbon dioxide in the atmosphere dropped and in this way it is replaced by oxygen, which contributes to the existence of vegetation.

The climatic changes that occurred helped the expansion of fauna to land, as was the case of tetrapods with a reptilian appearance, in addition to amphibians and insects. And after the Cambrian explosion there was a significant increase in marine life. Likewise, the flora that was diversifying on the land had great benefits, since at the end of the era there were already multiple forests with vascular features to be able to obtain nutrients from the soil.

Why is the Paleozoic Era important?

Its importance lies in the fact that it is the beginning of life on earth. With each of its processes, events developed that helped the appearance of new organisms in the ocean and then on earth. As was the case with the division of the continents, as well as the beginning of vegetation and many groups of animals and climates.

If all these events and evolutions of animals and plants had not taken place, the world today would not be known. This helped science to life on land and sea.