It has often been assumed that the Negro is physically inferior to other races and markedly distinguishable from them; modern science gives no authority for such an assumption.  The supposed inferiority cannot rest on color,[35] for that is “due to the combined influences of a great number of factors of environment working through physiological processes,” and “however marked the contrasts may be, there is no corresponding difference in anatomical structure discoverable."[36] So, too, difference in texture of hair is a matter of degree, not kind, and is caused by heat, moisture, exposure, and the like.

The bony skeleton presents no distinctly racial lines of variation.  Prognathism “presents too many individual varieties to be taken as a distinctive character of race."[37] Difference in physical measurements does not show the Negro to be a more primitive evolutionary form.  Comparative ethnology to-day affords “no support to the view which sees in the so-called lower races of mankind a transition stage from beast to man."[38]

Much has been made of the supposed smaller brain of the Negro race; but this is as yet an unproved assumption, based on the uncritical measurement of less than a thousand Negro brains as compared with eleven thousand or more European brains.  Even if future measurement prove the average Negro brain lighter, the vast majority of Negro brain weights fall within the same limits as the whites; and finally, “neither size nor weight of the brain seems to be of importance” as an index of mental capacity.  We may, therefore, say with Ratzel, “There is only one species of man.  The variations are numerous, but do not go deep."[39]

To this we may add the word of the Secretary of the First Races Congress:  “We are, then, under the necessity of concluding that an impartial investigator would be inclined to look upon the various important peoples of the world as to all intents and purposes essentially equal in intellect, enterprise, morality, and physique."[40]

If these conclusions are true, we should expect to see in Africa the human drama play itself out much as in other lands, and such has actually been the fact.  At the same time we must expect peculiarities arising from the physiography of the land—­its climate, its rainfall, its deserts, and the peculiar inaccessibility of the coast.

Three principal zones of habitation appear:  first, the steppes and deserts around the Sahara in the north and the Kalahari desert in the south; secondly, the grassy highlands bordering the Great Lakes and connecting these two regions; thirdly, the forests and rivers of Central and West Africa.  In the deserts are the nomads, and the Pygmies are in the forest fastnesses.  Herdsmen and their cattle cover the steppes and highlands, save where the tsetse fly prevents.  In the open forests and grassy highlands are the agriculturists.