PDF - Wallace Online

NATURAL SELECTIONan advance in mind rather than by a change in body. If,therefore, we are of opinion that he was not really man tillthese higher faculties were fully developed, we may fairlyassert that there were many originally distinct races of men ;while, if we think that a being closely resembling us in formand structure, but with mental faculties scarcely raised abovethe brute, must still be considered to have been human, weare fully entitled to maintain the common origin of all mankind.The Bearing of theseViews on the Antiquity of ManThese considerations, it will be seen, enable us to place theorigin of man at a much more remote geological epoch thanhas yet been thought possible. He may even have lived inthe Miocene or Eocene period, when not a single othermammal was identical in form with any existing species.For, in the long series of ages during which these primevalanimals were being slowly changed into the species which nowinhabit the earth, the power which acted to modify themwould only affect the mental organisation of man. His brainalone would have increased in size and complexity, and hiscranium have undergone corresponding changes of form, whilethe whole structure of lower animals was being changed.This will enable us to understand how the fossil crania ofDenise and Engis agree so closely with existing forms, althoughthey undoubtedly existed in company with largemammalia now extinct. The Neanderthal skull may be aspecimen of one of the lowest races then existing, just as theAustralians are the lowest of our modern epoch. We haveno reason to suppose that mind and brain and skull modificationcould go on quicker than that of the other parts of theorganisation and;we must therefore look back very far inthe past to find man in that early condition in which hismind was not sufficiently developed, to remove his body fromthe modifying influence of external conditions and the cumulativeaction of natural selection. I believe, therefore, thatthere is no a priori reason against our finding the remains ofman or his works in the tertiary deposits. The absence ofall such remains in the European beds of this age has littleweight, because, as we go farther back in time, it is natural