The Precambrian and the Mesozoic eons are different periods of life evolution on the Earth that reveals the gradual development of contemporary issues. The Precambrian Period is the earliest period that covers the span of formation of a tectonic plate and the appearance of primitive cell organisms that evolved to the first animals at the end of the period. The Mesozoic eon is a later period of the Earth evolution that is marked by the appearance of sophisticated animals. In addition, this era is known as the age of reptiles and dinosaurs. Both periods are rather distinguishing and the most important in the development of the Earth since they still contain some unknown areas for scholars.
The Precambrian era is the least studied period. In this period span from 4500 million years ago up to 452 million years ago when animals divergence appears. The Precambrian era is marked by the most important biological events that triggered the emergence of life on the planet. The Earth formation, tectonic plate movement, eukaryotic cells evolution, and the oxygen revolution highlight this period. Therefore, this eon is the most vital for the Earth’s development and life evolution that was finished by the appearance of the first multicellular organisms. Mesozoic eon covers the period from 248 million to 65 million years ago. The period gave rise to the rapid evolution of reptile species due to the specific warm and mild climate. Hence, dinosaurs were the prevailing animals on land, whereas the ocean was captured by the marine reptiles, and the air was occupied by pterosaurs. Considering the continent’s formation, it underwent significant changes. At the beginning of the period, there existed one continent Pangea that was gradually separated into the continents of the present form. The end of the era was marked by dinosaurs’ extinction, which is still a great mystery for paleontologists.
The second museum exhibition was devoted to the study of animals of the Mesozoic era. The exhibition presented the visitors with different kinds of dinosaurs and Archaeopteryx and species of Pterosaurs. Thus, Archaeopteryx is known as the earliest and the most primitive bird that lived in the late Jurassic period. The size of the bird could grow 1.6 feet. Many scholars believe that this “first” bird was a kind of transition between the dinosaurs and birds. According to the presented fossils, the evolved Archaeopteryxes had feathers. Pterosaurs appeared in the late Triassic period. Unlike Archaeopteryx, they have more sophisticated wings so that they are more adjusted to the powered flight. It is wrong to believe that Pterosaurs belonged to dinosaurs since it was a separate and shaped species. As Archaeopteryxes referred to the earlier Mesozoic period than Pterosaurs, it is reasonable to state that the latter is an evolved variant of the latter that completely breaks the tie between the dinosaurs and birds.
Both exhibitions helped me to get a deeper idea of the evolution process in the Precambrian and Mesozoic periods. The fossils presented in the exhibition are bright evidence of the transition of animals from primitive cell organisms to sophisticated species. These two periods that refer to different time span enable us to witness the peculiarities of evolution. In addition, the exhibition helped me to understand and differentiate the formation of various species and the main reasons for their extinction.