Kalasin

The Earth before Dinosaurs

 
 

Dinosaurs did not suddenly appear on earth. In fact, they were a part of a lengthy and continuous biological evolution.

You can learn about prehistorical animals from the story of the Paleozoic Era in the exhibition zone 3

The Paleozoic Era was a time before the appearance of dinosours, spanning 291 million years and being subdivided into 6 geological periods, chronologically shown as follows:

The Cambrian Period (542-488 million years ago): In the beginning of this period, no terrestrial life forms existed since it was too hot and arid, and the atmosphere was densely filled with carbon dioxide. Thus, first living organisms of this period formed in the sea; such as trilobites, graptolite, crinoids and shellfish.

The Ordovician Period (488-444 million years ago): The new species in this period was lamprey which was the jawless, eel-like fish vertebrates with no scales. There were large trilobite species, widespread corals and giant Nautiloids.

The Silurian Period (444-416 million years ago): Coral reefs started to appear on the ocean bed, while the lamprey evolved a lower jaw and later on became a heavily armored fish.

The Devonian Period (416-359 million years ago): Fish evolved many new spicies; such as, cartilaginous fish, lungfish, lobe-finned fish. In the late period some species of fish developed fins and breathing system with a lung, They became an amphibian that could live on land.

The Carboniferous Period (359-299 million years ago): During this period, the land climate was humid and plants grew well. The ancient plants included moss, tree ferns, horsetails, lepidodendron (scale trees) that could reach the height of a 5-story building. In late period, the amphibians evolved into reptiles. They no longer needed water to maintain the moisture in their bodies of lay eggs. Therefore, they could move deeper onto the land.

The Permian Period (299-251 million years ago):The swamps and peat swamp forests disappered, leaving behind vast regions of arid desert within the continental interior. Reptiles, who could better cope with these dryer conditions, rose to dominance in lieu of their amphibian ancestors. One of the top predators in the Early Permian is Dimetrodon, a vicious carnivorous, with the size of 3 meters in length and shaped like giant lizards. The most prominent feature of Dimetrodon was the large sail-like part on its back formed by elongated spines extending from the vertebrae.

By the time you reached the end of the three exhibition zones under “Paleozoic Era: The Evolutionary Change of Ancient Life”, you now have a good understanding and knowledge of the terrain's climate during each period on land and under the sea from the information provided in the showcases and the video screens along the walkway. The information is presented with a lively and exciting dimension to help us get a closer observation of the evolution of life in the prehistoric period of over 200 million years ago prior to the existence of dinosaurs.