La Cenozoic era starts with the Paleogene period y is a division of the geologic timescale. Thus began this period that spans 66 million years ago and ended approximately 23 million years ago. This period of time the evolution of mammals was quite remarkable despite the fact that they had to evolve from small species. These species were small in size if we compare it with the dinosaurs that existed in the cretaceous period.
In this article we are going to tell you all the characteristics, geology, climate, flora and fauna of the Paleogene period.
Key features
The name Paleogene comes from the most primitive forms of recent life. When we refer to recent life, we emphasize everything that exists since the Cenozoic era. At the beginning of the Paleogene there was a defragmentation speaking to geological level after the extinction of the dinosaurs at the end of the Cretaceous.
During this period North America and Greenland were finally separated from the continent of Eurasia. Thanks to this, the Norwegian Sea was created. This sea has existed for approximately 60 million years. At that time other oceans made their way, such as the Indian Ocean and the Atlantic. Thanks to this, it was able to expand in such a way that the species of flora and fauna could evolve individually. This is because each species was adjusted to a different ecosystem.
Due to these different environmental conditions, species develop diverse adaptations to survive in their environment. To learn more about the different characteristics of Paleogene fauna, you can check out this related link: Paleogene fauna.
Paleogene Geology
If we look at Australia and India, we can see that they were moving northeastward due to continental drift. The estimated speed of these continents' displacement was approximately 6 centimeters per year. As has been confirmed by more recent geological studies, the rate of continental drift has slowed considerably over time.
This northeastward shift caused the separation of Antarctica, which had remained near the South Pole since the origin of Pangea. About 40 million years later, India had almost completely separated from Africa and was about to collide with Asia to merge and form the Himalayas. The collision and formation of the Himalayas was the cause of closing the seaway of the great ocean Tethys. This occurred approximately 52 million years ago.
Changes in the weather
Throughout the Paleogene period there were acute climatic changes such as cooling in polar regions. At that time, the formation of coal and geological structures such as the Alps and the extensive Andean mountain range in South America also began.
This cooling did not see our planet after the extinction of the Triassic. Thanks to the decrease in global temperatures, the temporary cooling of the entire planet was allowed. Nevertheless, As the Paleogene period progressed, the temperature of the earth increased again. Due to this increase in temperatures, the earth began to become a tropical place in many places. In these areas the climate was completely different from the others.
Organisms had to adapt to the climate. They were able to survive despite the extinction that occurred in the previous period. One of these taxa was the angiosperms, which played a crucial role in the evolution of terrestrial flora. For more information on Paleogene fauna, you can review this specific article: Oligocene fauna.
Flora and fauna
The mammals that were found at that time were kept with features similar to what they are found today. Among them, the horse, the monkey, some variations of plants and others of mammals stand out. After the extinction in the late Cretaceous, most mammalian species thrived. These animals managed to diversify, becoming a distinctive species on the planet.
One of the most important mammal species was the primates, which evolved over time into Homo sapiens. If you'd like to learn more about Paleocene fauna, you can read the following article: Paleocene fauna.
Paleogene Stages
The Paleogene period is divided into three epochs with distinct geological, flora and fauna characteristics, and climate. These three stages are as follows: Eocene y.
Paleocene
It's the first stage with 65 million years and lasted until 56 million years. In this time stage, the total detachment of the Pangea continent occurred. All the tectonic plates separated eventually separated from Antarctica with Australia. Small communities of nocturnal mammals existed as both herbivorous and insectivorous feeding characteristics. Here we find rodents, birds and reptiles that would survive in this time.
Eocene
This stage lasted from 56 million years to 34 million years. Here the entire western hemisphere was the rise of huge mountain ranges by the collision of tectonic plates. The weather was hot and humid around this time. The difference in temperatures marked the equator, meridian and the poles. As for the fauna, primitive animals such as marsupials and lemurs made their appearance.
Oligocene
This stage lasted from 34 million years to 23 million years. At this time geology focused on closing the gap at the eastern end of the Tethys Ocean. All of this happened as Australia collided with Indonesia and the North American plate began to overlap over the Pacific Ocean. Regarding the weather, the global temperature was maintained in a subtropical and humid way. Shortly thereafter, the trend was changing towards global cooling with the arrival of an ice age. On the part of the fauna we find the creodonts that went to take important steps in their development. The mammals. They were established in order to dominate all terrestrial life on the planet. One of the most essential examples are the dwarf camels and the first elephants that did not have tusks. Furthermore, his troops were very short.
As you can see, the Paleogene period is loaded with development of both flora and fauna and quite interesting at the geological level. At the end of the Paleogene, the development of primates began, which would later evolve into the current human being. I hope that with this information you can learn more about the Paleogene period.