The Alpines are round skulled, of medium height and sturdy build both as to skeleton and muscles. The coloration of both hair and eyes was originally very dark and still tends strongly in that direction but many light colored eyes, especially gray, are now common among the Alpine populations of western Europe.
While the inhabitants of Europe betray as a whole their mixed origin, nevertheless, individuals of each of the three main subspecies are found in large numbers and in great purity, as well as sparse remnants of still more ancient races represented by small groups or by individuals and even by single characters.
These three main groups have bodily characters which constitute them distinct subspecies. Each group is a large one and includes several well-marked varieties, which differ even more widely in cultural development than in physical divergence so that when the Mediterranean of England is compared with the Hindu, or the Alpine Savoyard with the Rumanian or Turcoman, a wide gulf is found.
In zoology, related species when grouped together constitute subgenera and genera and the term species implies the existence of a certain definite amount of divergence from the most closely related type but race does not require a similar amount of difference. In man, where all groups are more or less fertile when crossed, so many intermediate or mixed types occur that the word species has at the present day too extended a meaning.
For the sake of clearness the word race and not the word species or subspecies will be used in the following chapters as far as possible.
The old idea that fertility or infertility of races of animals was the measure of species is now abandoned. One of the greatest difficulties in classifying man is his perverse predisposition to mismate. This is a matter of daily observation, especially among the women of the better classes, probably because of their wider range of choice.
There must have existed many subspecies and species, if not genera, of men since the Pliocene and new discoveries of their remains may be expected at any time and in any part of the eastern hemisphere.
The cephalic index is of less value in the classification of Asiatic populations but the distribution of round and long skulls is similar to that in Europe. The vast central plateau of that continent is inhabited by round skulls. In fact, Thibet and the western Himalayas were probably the centre of radiation of all the round skulls of the world. In India and Persia south of this central area occurs a long skull race related to Mediterranean man in Europe.
Both skull types occur much intermixed among the American Indians and the cephalic index is of little value in classifying the Amerinds. No satisfactory explanation of the variability of the skull shape in the western hemisphere has as yet been found, but the total range of variation of physical characters among them, from northern Canada to southern Patagonia, is less than the range of such variation from Normandy to Provence in France.
In Africa the cephalic index is also of small classification value because all of the populations are characterized by a long skull.