The fact of little or no modification having been effected since the glacial period, would have been of some avail against those who believe in an innate and necessary law of development, but is powerless against the doctrine of natural selection or the survival of the fittest, which implies that when variations or individual differences of a beneficial nature happen to arise, these will be preserved;
baina inolako indarrik ez du hautespen naturalaren edo egokienen biziraupenaren teoriaren kontra, honek hau inplikatzen baitu, alegia, banakoen arteko aldakuntza edo alde onuragarriak agertzea gertatzen denean, aldakuntzok kontserbatu eginen direla;