Page:Popular Science Monthly Volume 67.djvu/69

Rh in the case of albinos, etc.); atavism when a latent character becomes active, as when a lost character reappears; and saltation where a new combination of characters is produced and where the new form being crossed with the parent-stock does not give the Mendelian ratio, as in the case of the ancon ram, the japanned peacock, etc., if, in fact, these cases do not really follow the same rule of inheritance as do the elementary varieties.

De Vries has pointed out that each step, each mutation, may not have been any greater than the difference between the extremes of fluctuating variations, and if this is the case we see that evolution may have been a very gradual process, although not necessarily a very slow one. Darwin's idea that the process of evolution was very gradual is in full harmony with the mutation theory, but on the latter view we can better understand how evolution may at times have been relatively rapid, and that no such enormous periods are required for the process, as the Darwinian school is inclined to assume.

The time has come, I think, when we are beginning to see the process of evolution in a new light. Nature makes new species outright. Amongst these new species there will be some that manage to find a place where they may continue to exist. How well they are suited to such places will be shown, in one respect, by the number of individuals that they can bring to maturity. Some of the new forms may be well adapted to certain localities, and will flourish there; others may eke out a precarious existence, because they do not find a place to which they are well suited, and can not better adapt themselves to the conditions under which they live; and there will be others that can find no place at all in which they can develop, and will not even be able to make a start. From this point of view the process of evolution appears in a more kindly light than when we imagine that success is only attained through the destruction of all rivals. The process appears not so much the result of the destruction of vast numbers of individuals, for the poorly adapted will not be able to make even a beginning. Evolution is not a war of all against all, but it is largely a creation of new types for the unoccupied, or poorly occupied places in nature.

In the preceding pages I have tried to bring into contrast the point of view of the Darwinian school and the newer conception of the survival of elementary species. I have tried to show what selection has meant to the selectionist. They have never hesitated to take each particular character of an animal or plant, and dress it up in more perfect garments, while the body of the species, if I may so speak, has been left as it was before. There has been a continual tampering with the characters of the organism with the laudable intention of doing