Definition of Mesozoic Era

When time is understood in a long period, the word era is used. This is what happens with the geological stages of the Earth, which are known as you were geological. Geology is the science that establishes the chronology of the Earth and for this it is based on the interpretation of the strata. This chronology divides time into eons, eras, periods, and epochs. Focusing on the eras, it is possible to speak of four geological eras: Precambrian, Paleozoic, Mesozoic and Cenozoic.

During the two pre-Mesozoic stages, the Earth was made up of a single continent (Pangea), there was a cooling of the Earth crust, the seas began to form and the first unicellular living beings appeared and later the first reptiles, insects, fish and more primary amphibians.

Periods and particularities of the Mesozoic era

Geologists divide the Mesozoic or secondary era into three major periods: Triassic, Jurassic, and Cretaceous. All of them span from 251 million years to 65 million years ago. As for the most characteristic aspects, the most outstanding are the following:

- The division of Pangea evolves in several continental forms and there are frequent volcanic eruptions.

- The temperature of the Earth stabilizes and this causes the emergence of new vegetation in a generalized way.

- There is a great biological development in general and the first mammals and the first birds appear. The flora stands out for its exuberance and diversity.

- The most unique element of this era is the appearance, development and subsequent extinction of the dinosaurs.

The controversy of the extinction of the dinosaurs

There is no definitive theory as to what was the reason for its extinction at the end of the Mesozoic era. In fact, two possible explanations are contemplated:

1) the impact of an asteroid on Earth causing a climate change widespread and this would have consequences on the feeding basic dinosaur and

2) a stage of large volcanic eruptions that weakened the reproductive capacity of the dinosaurs.

In either of the two hypothesis, dinosaurs did not adapt to the new biological conditions that occurred. There are other explanations for this phenomenon, but with less recognition in the scientific community (venous plants that massively poisoned the dinosaurs, some hormonal change in their organism or the spread of a virus that ended with they).

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