[填空题]

[A] The impotence of creationism.
[B] Natural selection acts by competition.
[C] The role of natural selection in this colorful world
[D] The delicate hierarchy of the natural system.
[E] The agency of selection can account for more cases.
[F] No leaps in natural evolution.
As each species tends by its geometrical rate of reproduction to increase excessively in number; and as the modified descendants of each species will be enabled to increase by as much as they become more diversified in habits and structure, so as to be able to seize on many and widely different places in natural selection to preserve the most divergent offspring of any one species. Hence, during a long-continued course of modification, the slight differences characteristic of varieties of the same species, tend to be augmented into the greater differences characteristic of the species of the same genus.
41. __________
New and improved varieties wi