Thomas Henry Huxley said in his essay on the reception of On the Origin of Species: "The suggestion that new species may result from the selective action of external conditions upon the variations from their specific type which individuals present—and which we call "spontaneous," because we are ignorant of their causation—is as wholly unknown to the historian of scientific ideas as it was to biological specialists before 1858.
Thomas Henry Huxley berkata dalam esainya yang menanggapi On the Origin of Species: "Sugesti bahwa spesies baru dihasilkan dari tindakan selektif dari kondisi eksternal atas variasi dari tipe spesifik mereka yang individual saat ini—dan yang mereka sebut "spontan," karena mereka menghiraukan sebab mereka—sepenuhnya tak diketahui sejarawan gagasan saintifik seperti halnya para spesialis biologi sebelum 1858.