The main stages in the development of life on Earth: the table

There is a whole complex of sciences that study the main stages in the development of life on Earth, they all consider this issue in many ways, because this is a fundamental problem of natural science. The importance of paleontology, which studies the remains of plants and animals of past epochs, is very important, it is directly connected with the study of the evolution of the world.

This science studies the main stages in the development of life on Earth by reconstructing the appearance, external similarities and differences, the way of life of prehistoric animals that have already died out, and the approximate time of the existence of a particular species. But paleontology could not exist as a separate science without a multitude of others that help it, this science is at the junction of biological and geological disciplines. The main stages in the development of life on Earth are recreated with the help of such disciplines as:

• Historical geology;
• stratigraphy;
• paleography;
• comparative anatomy;
• Palaeoclimatology and many others.

All of them are interconnected, without one there can not be others.

Geological time

In order to identify the main stages in the development of life on Earth, it is necessary to have an idea of such a concept as geological time. How did people manage to identify some time periods? The whole secret lies in the study of rocks. The fact is that rocks that have arisen at a later time are superimposed on those that existed earlier. And the age of these layers can be determined by studying the remaining fossils.

Among all their diversity are the so-called leading fossils, which are the most numerous and widespread. Unfortunately, with the help of rocks you can not establish an absolute age, but here scientists do not stop, extracting this knowledge from volcanic rocks. As is known, they arise from magma. So, the main stages in the development of life on earth are singled out.

Briefly, the process of determining the absolute age of volcanic rocks is as follows: igneous rocks contain some elements, if their content is determined in a rock, then the absolute age of the rock can be determined quite accurately. Of course, errors are possible, but they do not exceed five percent. In addition, the age of our planet is determined, all scientists adhere to their numbers, but the common value is five billion years. Now we shall single out the main stages in the development of life on Earth, the table will be a good helper in this case.

Era, era and periods

Total paleontologists distinguish five stages or, in other words, the era, each of which is divided into periods, they all consist of epochs, and the last - from centuries. The Archean and Proterozoic eras are the most ancient times, covering about three billion years. They are distinguished by the total absence of vertebrates and terrestrial plants that appear in the "era of ancient life", which is more than three hundred million years old. Next comes the "era of average life", the Mesozoic (one hundred seventy five million years), its distinctive features - the development of reptiles, birds, mammals, plants, both flowering and angiosperms.

The last, the fifth, the era - Cenozoic, also called the "era of a new life," it began seventy million years ago, and we now live in it. This era is characterized by the rapid development of mammals and the appearance of man. Now we have analyzed the stages of the development of life on Earth briefly, suggest that we consider each era separately.

Archean era

This phase covers an interval from three thousand nine hundred to two thousand six hundred million years ago. Part of the sedimentary rocks, that is, formed by particles of the aquatic environment, remained in Africa, Greenland, Australia and Asia. All of them contain:

• Biogenic carbon;
• Stromatolites;
• Microfossils.

In this case, the origin of the second in this era is not entirely clear, for example, in Proterozoic they are associated with cyanobacteria. In the Archaean era, all organisms belonged to prokaryotes, and the source of oxygen was sulfates, nitrates, nitrites, and so on. All existing organisms on the planet resembled mold films, mainly located on the bottom of water bodies, in volcanic areas.

The Proterozoic Era

It is important to mention that this era is also divided into periods of three. In addition, this is the longest period of our history (approximately two million years). If we consider the boundary of this era and the Archean one, then it was during this period that our planet changed greatly, land and water spaces were redistributed. The earth was an icy wilderness, but at the end of this period, the percentage of oxygen reached one percent, which contributed to the stable life of unicellular organisms, bacteria and algae developed.

At the end of the Proterozoic, multicellular animals were formed, this period also has the name "Age of Jellyfish". Unicellular organisms are replaced by multicellular organisms, which qualitatively change the composition of the atmosphere, which contributes to the development of life on our planet.

Paleozoic

It includes as many as six periods, the first half is called the Early Paleozoic, and the latter half is late. The early and late Paleozoic are distinguished by the animal and vegetable world.

At the first stage, evolution can be traced exclusively to the underwater world, the settling of land began only in the Devonian, which refers to the Late Paleozoic.

Mesozoic Era

Now we turn to the most interesting era, rich in mysterious and diverse life, developing for about one hundred and eighty-five million years. As can be seen from the table, it is also divided into three periods. Cretaceous, compared with the Jurassic and Triassic, the longest (seventy-one million years).

As for the climate, it all depends on the location of the continents. Differences from our climate are that:

• He was much warmer than the modern;
• There were no temperature differences between the equators and poles.

In addition, the air was moist, which contributed to the rapid development of living organisms.

If we turn to fauna, the most unique group is known dinosaurs. They took dominant positions over other forms of life due to the structure of their body, physiological data and reactions.

So, analyzing the question of what are the main stages in the development of life on Earth, we have identified five stages. For the full picture, it remains to consider one more. We suggest starting right now.

The Cenozoic Era

This is a new era that continues to this day. Continents have acquired a modern look, the last dinosaurs have disappeared, plants and animals predominate on Earth, which are quite familiar to us. We examined the main stages in the development of life on Earth briefly, dismantled all the steps separately, the goal set by us was achieved.