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Fossils can be found everywhere.<br> | Fossils can be found everywhere.<br> | ||
How can we determine the age of rocks ? | ===How can we determine the age of rocks ?=== | ||
==Why are fossils important for Evolution study?== | ==Why are fossils important for Evolution study?== | ||
Version du 19 avril 2011 à 14:23
What is a fossil?
A fossil looks like a stone, but it is not really a stone. It is a memory of an animal that lived a long time ago. The addition of a time factor and chemical reactions formed it. We will explain precisely how a fossil is formed later.
How are fossils formed?
The formation of a fossil is called fossilization. It begins as the rest of a dead organism (animal or plant) falls in water or in a wet environment. The organism's body's decompose. As this happens, the rest of the animal is covered by sediments during ages. The sediments and the bones are transformed in a kind of stone which wears the track of the organism. Erosion and extreme climatic phenomena reveals the fossil. That is why we can discover animals that were born thousands or millions of years ago!
Are fossils easily found?
Fossils can be found everywhere.
How can we determine the age of rocks ?
Why are fossils important for Evolution study?
Fossils are the evidence of evolution. Without them, we would have only a "theoric" sketch of how species evolved throughout the centuries.
What is the "fossil record" ?
How is formed a fossil?
The very first fossils found..
What information can we find in fossils ?
Which problems can we have with fossils ?
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