Kipling, Darwin and the law of the jungle


from The Law of the Jungle:

"Now this is the Law of the Jungle — as old and as true as the sky;
And the Wolf that shall keep it may prosper, but the Wolf that shall break it must die.
As the creeper that girdles the tree-trunk the Law runneth forward and back —
For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack."

If Kipling is correct how does this compare with what Charles Darwin had to say about the wolf as one of this two main examples in "The Origin of Species" of natural selection by mean of competition between members of the same species?