II. The Dispersive Elements.
These have been of the utmost moment in the history of the species, and a controlling factor in the records of every people. They are derived from two quite different impulses in human nature; the one, a natural propensity to roam, the other, a predisposition to contest.
Both have been favored by the ability of the species to adapt itself to its surroundings, far surpassing that of any other animal. There is no zone and no altitude offering the necessary food supplies that man does not inhabit. The cat, with its traditional “nine lives,” perishes in the upper Andes, where men live in populous cities. No one breed of dogs can follow man to all latitudes. His powers of locomotion are equally surprising. He can walk the swift horse to death, and his steady and tireless gait will in the long-run leave every competitor behind. An Indian will track a deer for days and capture it through its utter fatigue. A Tebu thinks little of passing three days under the sun of the Sahara without drinking. Such powers as these endow man with the highest migratory faculties of any animal, and give rise to or have been developed from
1. The Migratory Instincts.
Many species of animals, especially birds, change their habitat with the seasons, the object usually being to obtain a better food supply. So do most hunting and fishing tribes, and for the same reason. Often these periodical journeys extend hundred of miles and embrace the whole tribe.
This must also have been the case with primeval man when he occupied the world in “palæolithic” time. His home was along the shores of seas and the banks of streams. Up and down these natural highways he pursued his wanderings, until he had extended his roamings over most of the habitable land.
What prompted him and all savage tribes is not always the search for food. The desire for a more genial climate, the pressure of foes, and often mere causeless restlessness, act as motive forces in the movements of an unstable population. Certain peoples, as the Gypsies, seem endowed with an hereditary instinct for vagabondage. The nomadic hordes of the Asiatic steppes and the wastes of the Sahara transmit a restlessness to their descendants which in itself is an obstacle to a sedentary life.
Such vagrant tribes became the colporteurs and commercial travellers of early society. They invented means or transportation, and conveyed the products of one region to another. Only of late have we learned to appreciate the wide extent of pre-historic commerce. Long before Abraham settled in Ur of the Chaldees (say 2000 B. C.), a well-travelled commercial road stretched from the cities of Mesopotamia, through Egypt to the Pillars of Hercules, and thence into Europe.[34] When Hendrick Hudson sailed into the bay of New York, the commercial relations of the tribes who lived on its shores had already extended to the coast of the Pacific.[35]
These lines of early traffic were also the lines of the migrations of nations. They were fixed by the physical geography of regions, and have rightly attracted the careful attention of ethnographers. Along them, nation has blended into nation, race fused with race. The conviction that early man was not sedentary, but mobile, by nature a migratory species, wandering widely over the face of the earth, is one which has been brought home to the ethnologist by the science of prehistoric archæology, and it is full of significance.