Those who were deficient in the spirit of independence must have shrunk from these wild expeditions in search of new homes to be won only by the sword, or must in the main have failed to attain the end; remaining at home, or returning there after failing in the enterprise to which they proved unequal, to finish their days as bachelor uncles at the paternal hearth. This process, carried on for many generations, would lead to the evolution of just those qualities which are characteristic of their descendants in all the many parts of the earth where they now rule. Not only must such social selection have been operative during the period of settlement of Scandinavia; but each great migration to a new area must have sifted out the most independent and enterprising spirits to be the founders and fathers of the new branch of the race[119]. Thus the descendants of the pilgrim fathers were the product of three such processes of severe selection; the migration from Scandinavia to Northern Germany; that from Germany to England; and that from England to America. No wonder that they proved themselves well able to cope with the hardships and dangers of a new continent inhabited by savages only less fiercely tempered than their own stock by many generations of warfare! When we thus find the same institutions and the same mental traits characterising, from the dawn of history to the present time, all the widely separated branches of one racial stock and of this stock alone, we realize how powerful over the destiny of nations is the influence of racial character formed in the long prehistoric ages; we see how futile it is to attempt to explain the mental traits of a people by the history of their political institutions during a few recent centuries; we understand that these institutions are the effects, not the causes, of those mental qualities and that, even among the peoples who have attained the highest degree of civilisation, racial qualities remain of supreme importance. THE CROSSING OF RACES Before passing on to the consideration of evolutionary changes during the historic period, a few words must be said about the crossing and blending of races. Such blending has been, no doubt, one of the principal causes of the great variety of human types at present existing on the earth. It has been going on for long ages in almost all regions; but especially in Europe and Africa. All existing stocks (with few exceptions) are the products of race-blending. No one of the existing European peoples is of unmixed stock; every one is the product of successive mixtures and blendings of allied stocks; and the mixing and blending still goes on; while in America (both north and south) the greatest experiments in race-blending that the world has yet seen are taking place before our eyes.