প্রাকৃতিক নির্বাচন কথাটি যে গ্রন্থে সর্বপ্রথম করা হয় সেই গ্রন্থটি কে লিখেছিলেন ?
Herbert Spencer first used the phrase, after reading Charles Darwin's "On the Origin of Species", in his "Principles of Biology" (1864), in which he drew parallels between his own economic theories and Darwin's biological ones: "This survival of the fittest, which I have here sought to express in mechanical terms, is that which Mr. Darwin has called 'natural selection', or the preservation of favoured races in the struggle for life."
Charles Darwin