Quote 28
Guided by that instinct which came from the old hunting days of the primordial world, Buck proceeded to cut the bull out from the herd. It was no slight task. (7.28)
One of Buck’s last and greatest challenges—killing a bull—demonstrates the completion of his transformation. We see his physical and mental prowess against a formidable opponent.
Quote 29
But in the main they were the wild wolf husky breed. Every night, regularly, at nine, at twelve, at three, they lifted a nocturnal song, a weird and eerie chant, in which it was Buck's delight to join. (3.27)
Buck is initially drawn to the wild because of the camaraderie he feels with the wolves.
Quote 30
With the aurora borealis flaming coldly overhead, or the stars leaping in the frost dance, and the land numb and frozen under its pall of snow, this song of the huskies might have been the defiance of life, only it was pitched in minor key, with long-drawn wailings and half-sobs, and was more the pleading of life, the articulate travail of existence. (3.28)
London connects the wild, natural world with vitality. Buck is most alive in the wild.