Fossils are evidence of life that existed before us, at the time when technology is just a thought or even barely a thought, back when people are not concerned of finding low cost dedicated server but instead concerned of survival. Fossils are important because it tells us a lot about the world we live in before the world that we know of today.
Fossil – What is it?
Fossils are the stone remains of animals or plants that once lived in our planet. Fossils can be the bones of an animal that lived million years ago, it could also be its footprints that were embedded in the sand. In most cases, only the skeleton of animals after millions of years are found. However, there are times when the whole animal like a woolly mammoth gets trapped in the ice are discovered after several years.
The ice stays frozen for thousand of years and paleontologist are lucky to find a whole creature that is barely changed over time or an insect get stuck in tree sap that hardened to a clear material called amber. These creatures look just the way they did when they first wandered into the sap millions of years ago.
How Fossils Are Formed
Most dinosaur fossils are formed by mold and cast. Imagine a Stegosaurus drowns in a river and it’s body sinks to the bottom of the riverbed. The flesh of the animal rots away or eaten by smaller creatures. Eventually only the bones are left.
Mud and sand called sediment cover this elephant over many years. More layers of sediment fall on the skeleton over time the floor of the river sinks from the weight of the sediment. The lower layers of soft mud and sand are pressed into hard rock. The skeleton is completely surrounded by compressed stone.
The bone is slowly washed away by little trickles of the water. This water is called groundwater. The bones form an open space where the exact shape of the animal’s skeleton takes form. The open space created is called the natural mold where the groundwater brings tiny pieces of rock into those empty spaces.
After millions of years, these tiny rock pieces fill the mold. The rock is pressed further and further underground. Over time the entire skeleton mold becomes solid rock. Many years later, the rock around the skeleton surfaces to the earth. This can happen during an earthquake or as mountain rise naturally.
The top layers of rock are worn away by wind and rain. Slowly the wind and the rain show the fossils outside the world. Not all fossils rise to the surface. Many times they remain under layers and layers of rock and paleontologists have to dig a long time to find them.