This section is from the book "Principles Of Sociology With Educational Applications", by Frederick R. Clow. Also available from Amazon: Principles of sociology with educational applications.
A piece of land has its use determined for it by natural selection. It is put to the purposes which the people occupying it for the time being have found by experience to be most advantageous. Take any farm or city lot for example. Only a minute study of local history would give any idea of the varied uses to which it has been put in time past. There were doubtless many failures, and some uses were profitable for a time which later became unprofitable. Different locations compete with one another; sites for harbors, water powers, manufacturing, trade, residence. A region that surpasses every other in producing a desirable kind of fruit uses its advantage to the full, regardless of the effect on competing regions; the owners are almost as free from compunction about the matter as is a tree that overtops another tree in such a way as to deprive it of sunlight.
. . . The struggle for existence is a process in which the individual and nature are the parties. ... - Sumner, Folkways, p. 16.
Social activity follows the line of least resistance. Population is relatively dense in warm climates. Colonization follows coast lines and river valleys. Expanding states respect the territory of strong rivals and encroach upon the domain of the weak. - Giddings, Principles of Sociology, p. 369.