-Charles Darwin never used the word "evolution" in Origin of Species nor did he use the phrase, survival of the fittest.
Darwin did not use the phrase "survival of the fittest" in the first edition, but in later editions (certainly in
the sixth edition) he had adopted it from Spencer, who coined it. From
chapter III:
I have called this principle, by which each slight variation, if useful, is preserved, by the term natural selection, in order to mark its relation to man's power of selection. But the expression often used by Mr. Herbert Spencer, of the Survival of the Fittest, is more accurate, and is sometimes equally convenient.
And in the same edition, he has actually retitled
chapter IV: "NATURAL SELECTION; OR THE SURVIVAL OF THE FITTEST".
Edited by Dr Adequate, : No reason given.
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