Unification of race in islands.
Islanders are always coast dwellers with a limited hinterland. Hence their stock may be differentiated from the mainland race in part for the same reason that all coastal folk in regions of maritime development are differentiated from the people of the back country, namely, because contact with the sea allows an intermittent influx of various foreign strains, which are gradually assimilated. This occasional ethnic intercrossing can be proved in greater or less degree of all island people. Here is accessibility operating against the underlying isolation of an island habitat. The English to-day represent a mixture of Celts with various distinct Teutonic elements, which had already diverged from one another in their separate habitats—Jutes, Angles, Saxons, Danes, Norse and Norman French. The subsequent detachment of these immigrant stocks by the English Channel and North Sea from their home people, and their arrival in necessarily small bands enabled them to be readily assimilated, a process which was stimulated further by the rapid increase of population, the intimate interactive life and unification of culture which characterizes all restricted areas. Hence islands, like peninsulas, despite ethnic admixtures, tend to show a surprising unification of race; they hold their people aloof from others and hold them in a close embrace, shut them off and shut them in, tend to force the amalgamation of race, culture and speech. Moreover, their relatively small area precludes effective segregation within their own borders, except where a mountainous or jungle district affords a temporary refuge for a displaced and antagonized tribe. Hence there arises a preponderance of the geographic over the ethnic and linguistic factors in the historical equation.
The uniformity in cranial type prevailing all over the British Isles is amazing; it is greater than in either Spain or Scandinavia. The cephalic indices range chiefly between 77 and 79, a restricted variation as compared with the ten points which represents the usual range for Central Europe, and the thirteen between the extremes of 75 and 88 found in France and Italy.[850] Japan stands in much the same ethnic relation to Asia as Britain to Europe. She has absorbed Aino, Mongolian, Malay and perhaps Polynesian elements, but by reason of her isolation has been left free to digest these at her leisure, so that her population is fairly well assimilated, though evidences of the old mixture can be discerned.[851] In Corsica and Sardinia a particularly low cephalic index, dropping in some communes to 73, and a particularly short stature point to a rare purity of the Mediterranean race,[852] and indicate the maintenance here of one ethnic type, despite the intermittent intrusion of various less pure stocks from the Italian mainland, Africa, Phoenicia, Arabia, and Spain. The location of the islands off the main routes of the basin, their remoteness from shore, and the strong spirit of exclusiveness native to the people,[853] bred doubtless from their isolation, have combined to reduce the amount of foreign intermixture.
Remoter sources of island populations.
Islands do not necessarily derive their population from the land that lies nearest to them. A comparatively narrow strait may effectively isolate, if the opposite shore is inhabited by a nautically inefficient race; whereas a wide stretch of ocean may fail to bar the immigration of a seafaring people. Here we find a parallel to the imperfect isolation of oceanic islands for life forms endowed with superior means of dispersal, such as marine birds, bats and insects.[854] Iceland, though relatively near Greenland, was nevertheless peopled by far away Scandinavians. These bold sailors planted their settlements even in Greenland nearly two centuries before the Eskimo. England received the numerically dominant element of its population from across the wide expanse of the North Sea, from the bare but seaman-breeding coasts of Germany, Denmark and Norway, rather than from the nearer shores of Gaul. So the Madeira and Cape Verde Isles had to wait for the coming of the nautical Portuguese to supply them with a population; and only later, owing to the demand for slave labor, did they draw upon the human stock of nearby Africa, but even then by means of Portuguese ships.
Double sources.
Owing to the power of navigation to bridge the intervening spaces of water and hence to emphasize the accessibility rather than the isolation of these outlying fragments of land, we often find islands facing two or three ways, as it were, tenanted on different sides by different races, and this regardless of the width of the intervening seas, where the remote neighbors excel in nautical skill. Formosa is divided between its wild Malay aborigines, found on the eastern, mountainous side of the island, and Chinese settlers who cultivate the wide alluvial plain on the western side.[855] Fukien Strait, though only eighty miles wide, sufficed to bar Formosa to the land-loving northern Chinese till 1644, when the island became an asylum for refugees from the Manchu invaders; but long before, the wider stretches of sea to the south and north were mere passways for the sea-faring Malays, who were the first to people the island, and the Japanese who planted considerable colonies on its northern coasts at the beginning of the fifteenth century. [See map page 103.]