Darwin's theory of evolution predicts how different species evolve.

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He landed, camped there, left and returned, studied, researched and conceived his earth-shaking theory of evolution, On the Origin of Species, in 1859.

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He did indeed develop a theory that species evolve and that the two crucial conditions of evolution were time and favourable conditions, in other words that species adapt to their environment.

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These findings would not have surprised Charles Darwin, who in addition to theorizing on evolution in The Origin of the Species, also developed the Facial Feedback Response Theory, which suggests that the act of smiling actually makes us feel better (rather than smiling being merely a result of feeling good).

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