Charles darwin theory of natural selection

Ideas aimed at explaining how organisms change, or evolve, over time date back to Anaximander of Miletus, a Greek philosopher who lived in the s B.C.E.

Noting that human babies are born helpless, Anaximander speculated that humans must have descended from some other type of creature whose young could survive without any help. He concluded that those ancestors must be fish, since fish hatch from eggs and immediately begin living with no help from their parents.

From this reasoning, he proposed that all life began in the sea.

Anaximander was correct; humans can indeed trace our ancestry back to fish.

Charles darwin theory of natural selection summary

His idea, however, was not a theory in the scientific meaning of the word, because it could not be subjected to testing that might support it or prove it wrong. In science, the word “theory” indicates a very high level of certainty.

Scientists talk about evolution as a theory, for instance, just as they talk about Einstein’s explanation of gravity as a theory.

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