What is a Fossil?
Fossils are the remains of long-dead plants and animals that never rotten. After many years, they have been preserved in the Earth’s crust. There are three types of fossils. Fossils may be the remains of the organism itself, such as a bone or piece of wood. Another type of fossil is an impression left by an organism in the sediment, such as a footprint or the print of a leaf. A third type of fossil is a trace made by an animal when it was alive, a burrow made by a worm, for example.
How are fossils formed?
For fossilization process to occur, the organism (or part of it) has to be buried quickly in the sediment. This might happen during a flood or when a volcano erupts and spews out a lot of ash. Then chemical alterations occur for many years. Minerals are added or removed, helping to preserve the remains.
Let’s think about a shark’s tooth. Sharks lose their teeth as they grow new ones. The tooth falls out into the mud or sand, where it may disintegrate (a) or get buried (b) Chemical processes may dissolve the tooth and it would not become a fossil (c). Or the minerals from the sediment or water might fill empty spaces in the tooth, which would cause the tooth to turn to rock and fossilize (d). This process takes thousands of years. The tooth can be different colors depending on which minerals are absorbed. After many years, if the ground where the tooth is buried is eroded, we might find this fossil tooth.
How can We find fossils?
Generally, fossil shark teeth are found in marine sediments like sands, mud, or clays. In Panama, they are commonly found in the Gatun Formation. This formation of rocks is around 10 million years old and crops out in different localities very close to Colon.
When you are looking for a fossil shark tooth, you have to walk all over the area, looking closely at the ground. Generally, you can spot a tooth because it is shiny.