WEIT 2012 Chap2

WRITTEN IN THE ROCKS

What is a fossil?

A fossil is an animal or a plant which has been preserved by...

A fossil is really useful. Scientists condider them as a record, in the way that it gives to the scientists a lot of indications about the ancestors of species and thus indications about evolution.

Where do scientists find fossils?

Scientists must brave a lot of dangers to hope finding fossils. Finding them demands a lot of time, it's expensive and risked. Indeed, scientists must face diseases, political troubles and inhospitable places, where the fossils are usually found, such as the Sahara Desert. They need also a lot of luck to find the place where a fossil is. Furthermore, once the scientists have discovered them, they must then extract, prepare and describe them.

Why are fossils so important for Evolution?

"The story of life on earth is written in the rocks."
Thanks to fossils, scientists can understand the evolution of species and know how a common ancestor of a specific fossil looks like. Without them, we will only know relationships between species through similarities in form, development ans DNA sequence, but not when a species appeared on earth or which is its common ancestor Advances in sciences have provided and will provide precious insights from the past.

References

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