It is believed by some that there were periods in the history of organisms when evolution took place more rapidly than at other times; perhaps this was due to variability occurring more extensively, which again may have been partly due to changes in the environment. There is no reason to believe that variation (which is the material that makes evolution possible) occurs uniformly. There is no need to touch further upon these yet unsolved problems of Biology; at all events we find that in decorative art evolution has been spasmodic or discontinuous, that there are periods of quiescence and of activity. I have already suggested that the isolation of a people and uniformity in their existence will tend to stagnation in art, and that intercourse with other peoples, whether by trade, war or migration, serves as a stimulus to artistic expression.
To return to our more immediate subject, consciousness of purpose has extremely little to do with human evolution, nor has it much more to say to the evolution of patterns among primitive peoples.
The selection of one design instead of another, or of a particular part of a design, is a conscious act, but probably in the great majority of cases an unreasoning one. And the selection is limited to that individual object. It is inconceivable that a savage should copy or adapt a certain design because it promises to develop into a more pleasing pattern. While there is a certain amount of conscious selection, the variation as a whole of any design is an entirely unguided operation so far as the intelligence of the human units is concerned.
II. THE GEOGRAPHICAL DISTRIBUTION OF ANIMALS AND OF DESIGNS.
No part of the study of Biology is more fascinating than that which deals with the geographical distribution of organisms, especially when treated by such a master as Alfred Russel Wallace. The geographical distribution of art is as yet uninvestigated, but with careful and capable handling we may expect it to yield results not less interesting than those of the distribution of animals. It is needless to point out that the subject is peculiarly difficult, but as John Ray said two hundred years ago concerning the study of Natural History, "much might be done did we but endeavour, and nothing is insuperable to pains and patience."