Fossils

Fossil are the remains of living organisms. Fossils can be actual remains or replacement remains. Fossils require the right condition to be formed. A living organism has around a one in a million chance of becoming a fossil if conditions are right! The fossil record is incomplete because of the rarity of organism becoming a fossil. Fossils however, help us to understand the past in that they show what life was like and the climate they lived in. Many types of fossils become index fossils in that they show units of time throughout geologic history. There are many types of fossils some these include: Trace Fossils, Molds & Casts, Amber Fossils, Ice Fossils, Mummified Fossils and Petrifaction Fossils.

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Trace Fossils

Trace Fossils are not actual fossils remains. They are tracks left behind by the organism.

Molds & Casts

Molds and Casts are replacement type fossils. When an organism dies and is imprinted into the mud, it leaves an impression behind. Eventually the organism dissolves and leaves a mold of itself behind. Sediment files the mold and makes a perfect copy of the original and this called a cast. Much like when a artist creates a mold and pours metal into it to cast a statue.

Amber Fossils

Amber is tree sap that drips from conifers (Pines.) This sap drips unto insects below it trapping the insect in the sap. The sap eventually turns rock hard and the insect remains are forever preserved in the amber.

Ice Fossils

Ice Fossils are actual flesh remains of the organism. They become trapped in ice and remain frozen until they thaw. Good example of a ice fossil are Wooly Mammoths, which are often found in the Arctic.

Mummified Fossils

Mummified Fossils are often found in caves of desert regions. The lack of moisture in the air in combination with both heat and wind dry out the flesh and create a leather texture preserving the organism.

Petrifaction Fossils

Petrifaction Fossils are preserved through mineral replacement. In petrifaction an organism is buried quickly and the minerals replace cells in the organisms one for one. After a period of time the organism is turn to stone. A good example of this type of fossil is petrified wood.