Some variation of the ethnic types has resulted under the protracted selective process to which the several types and their hybrids have been subjected during the prehistoric and historic growth of culture.
This necessary variation of the types themselves, due to a selective process of considerable duration and of a consistent trend, has not been sufficiently noticed by the writers who have discussed ethnic survival.
The argument is here concerned with two main divergent variants of human nature resulting from this, relatively late, selective adaptation of the ethnic types comprised in the Western culture; the point of interest being the probable effect of the situation of today in furthering variation along one or the other of these two divergent lines.
The ethnological position may be briefly summed up; and in order to avoid any but the most indispensable detail the schedule of types and variants and the scheme of reversion and survival in which they are concerned are here presented with a diagrammatic meagerness and simplicity which would not be admissible for any other purpose.

The man of our industrial communities tends to breed true to one or the other of three main ethic types; the dolichocephalic-blond, the brachycephalic-brunette, and the Mediterranean--disregarding minor and outlying elements of our culture.

But within each of these main ethnic types the reversion tends to one or the other of at least two main directions of variation; the peaceable or antepredatory variant and the predatory variant.

The former of these two characteristic variants is nearer to the generic type in each case, being the reversional representative of its type as it stood at the earliest stage of associated life of which there is available evidence, either archaeological or psychological.

This variant is taken to represent the ancestors of existing civilized man at the peaceable, savage phase of life which preceded the predatory culture, the regime of status, and the growth of pecuniary emulation.