The different epochs that divide the geological time scale are known as geological eras . These are certain periods of time comprising thousands of years whose classification is based on several factors, so that it is easier to study and understand the biological and geological changes, including those afflicting the Earth throughout its history. Geological Ages
Precambrian
It is the oldest geological age and its duration has extended in such a way to surpass 4 million years
It was sometime around this time that the earth’s crust began to divide into continents and oceans, as well as being able to populate large groups of aerobic algae and bacteria. Furthermore, tectonic plates emerged that would lead the continents adrift.
Some scientists opine that these first forms of marine life were responsible for the generation of oxygen, serving as a starting point for the evolution of marine creatures and already completely dependent. Geological Ages
Paleozoic
This geological era began approximately 750 million years ago, ending 500 million years later.
At the beginning of the Paleozoic era the continents were located south of the equator and began to break up into smaller pieces, thus, they would be affected by glaciers.
In relation to animal life, this era was characterized by the appearance of molluscs and fish, mainly because they began to leave the sea and enter inland, giving way to the first amphibians and reptiles. Geological Ages
Mesozoic
As a result of the evolution of these animals that experienced the Paleozoic era, another epoch emerged, the Mesozoic, known as the age of the dinosaurs, which extended its reign for nearly 180 million years. In addition, the first species of birds and mammals also appeared, making this geological era the most important for the study of paleontology. Geological Ages
On the other hand, continental drift led to the definitive rupture of Pangea , the first continent that fragmented and formed smaller ones. Thus North America broke away from Africa, while India and South America did the same with Antarctica.
Cenozoic
The last geological age began only 65 million years ago and continues to this day
In turn, it can be divided into two major periods: the tertiary and the quaternary. During that time there was the last great glaciation, the continents were adopting their current form, emerging the great mountain ranges and even with the extinction of the dinosaurs, the mammals prevailed. Geological Ages
