A it was geological is a geo chronological unit, a time division used in the historical geology to determine the geologic timescale.
Division of time that geology uses to study and understand the history of the planet and the species that stepped on it and inhabit it today
It consists of periods of time that include millions of years and the classification is carried out in relation to various factors, so that it is easier to study and understand the changes, both geological and biological that have occurred on the planet throughout of all its history.
It should be noted that the basic unit is age and in descending order the established hierarchy would be: age, epoch, period, era, eon.
The era, for its part, implies a extremely long period of time, that is, millions of years, which in turn involves both biological and geological processes.
Meanwhile, the history of our planet earth is divided into eras to thereby make the understanding of the evolution of the world and the beings that compose it much more accessible.
The eras and their main characteristics: Precambrian, Paleozoic, Mesozoic and Cenozoic
The geological eras are four, the precambrian era It is considered the longest of the stages of the earth, having lasted around 4,027 million years and in it substantial issues were produced such as: formation of the lithosphere, the hydrosphere, the oceans and the atmosphere that would make the development of life.
Algae, fungi and the first bacteria were also said to be present at this time; It is worth mentioning that the forms of life were extremely simple compared to later ages.
According to the studies that resulted later, it was concluded that these first forms of marine life were the ones that generated oxygen and served as a starting point for marine species to evolve and depend on it at all.
The Paleozoic or Primary Era It spanned more than 290 million years and among the highlights is that in it the earth is divided into a small number of continents.
When this era began, the continents were located south of the Equator and began to divide into smaller parts and would suffer the processes of glaciation.
Regarding the animals, those of shell or exoskeleton abounded, even several of the living beings that lived in the water emerged towards the land, such is the case of mollusks and fish and this gave way to the appearance of the first reptiles and amphibians.
At this time fish, mollusks, amphibians, reptiles, among so many others, appeared.
The age Mesozoic or secondary and also known as the age of the dinosaursIt lasted approximately 186 million years and in them there was no orogenic movement; the continents were reaching their present appearance.
The climate was characterized by its warmth, which allowed the fabulous evolution and diversification of animals, beginning to appear the first specimens of mammals and birds, a fact that caused this era to become the most relevant at the time of studies. paleontological.
The continental break of Pangea will be generated, the first of the super continents that will end up decomposing into smaller ones
North America separated from Africa and India and South America did the same with respect to Antarctica.
And the was Cenozoic or Tertiary It began about 65 million years ago and extends to our present day.
Among the most notable of this era stands out the glaciation, the collision of Asia with India and Arabia with Eurasia giving rise to the alpine folding that originated the great mountain ranges of southern Europe and Asia.
After the disappearance of the dinosaurs, the most complex forms of life prevail: mammals, higher primates, homo sapiens and humans.
The fundamental role of paleontology
Paleontology is the discipline that deals with the study of past living beings from the examination of fossil remains, and for example it is a fundamental leg when determining what happened and the characteristics of each of the you were we have identified.
The fossil remains were preserved over the years by the minerals that were able to petrify them.
It is presumed that the earth has an age of more than four thousand five hundred million years, while sciences such as the aforementioned paleontology, and others that deal with the study of our planet, have focused their research on the rocks and fossils that they found.
The rocks allowed us to know precisely the age of the planet, the temperatures that persisted in each of the eras, the movements that occurred in the earth's crust and the variations that produced the distribution of the land and waters.
