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 We think it was between 3-4.5 billion years ago  Why can we not be certain how life on earth began?

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Presentation on theme: " We think it was between 3-4.5 billion years ago  Why can we not be certain how life on earth began?"— Presentation transcript:

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2  We think it was between billion years ago  Why can we not be certain how life on earth began?

3  How are fossils made?  How do we know the age of a fossil?

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5  Fossils provide evidence of how much or how little different organisms have changed since life began on earth

6  3 main reasons why species become extinct a. Destruction of habitat- environment changes too quickly b. A new predator or diseases kills them c. They can’t compete with another species for food.

7  States that all species of living things have evolved from simple life forms which first developed more than 3 billion years ago.

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9  If an organism is born with a useful characteristic which means that the organism is well suited to the environment. It will breed and pass on this useful characteristic.  Mutations can lead to rapid changes in species  What happens if the mutation is a disadvantage?

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12  Why was Darwin's theory of natural selection not agreed with by everyone?

13  He said that if a characteristic was used a lot then it would become more developed and its offspring would have these characteristics  Eg giraffes long necks

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