Principles of western civilisation

60 WESTERN CIVILISATION CHAP.

egg, and they continue to receive sustenance and care for a lengthened period after birth. In the mammals themselves we see the same stream of development in progress in the rise from the marsupials to the placentals. Entire species and types, failing, as it were, under the burden of the future, gradually drop out of the race as Natural Selection, dominating the evolutionary process towards a particular end over immense stretches of time, carries the leading shoot of life gradually upwards towards man.

As progress has continued toward increasing complexity of structure in the individual, on the one hand, so has the interval of development to be spanned in the life of every individual continued to be lengthened out, on the other. Heavier and heavier has accordingly grown the burden of parenthood. More and more insistent under the conditions of progress has become the demand of the future upon the present, on the one hand; more and more urgent under the operation of Natural Selection has grown the necessity for meeting it efficiently, on the other.

In all this we have only the simplest and most obvious example at close quarters of the action of a principle which we must regard as operating—and as a rule under much more complex conditions—in every direction throughout life.‘ In the operation

1 Tt is interesting to notice in this connection the grounds upon which Mr. A. R. Wallace has recently rejected Darwin’s original view as to the origin of a multitude of colours, markings, plumes, appendages, etc., through the instrumentality of sexual choice made, as was assumed by Darwin, in accordance with some internal esthetic standards in the mind of the individual of unexplained origin. Mr. Wallace has come to regard the display of colours, plumes, and appendages in question, simply as the external indication of maturity and vigour in the male, and, therefore, on that account necessarily attractive to the female. The esthetic standard in the sexes is, in fact, itself