What evidence I'd there that bucks slowly losing his domesticated ways? Chapter 2

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He swiftly lost the fastidiousness which had characterized his old life. A dainty eater, he found that his mates, finishing first, robbed him of his unfinished ration. There was no defending it. While he was fighting off two or three, it was disappearing down the throats of the others. To remedy this, he ate as fast as they; and, so greatly did hunger compel him, he was not above taking what did not belong to him. He watched and learned. When he saw Pike, one of the new dogs, a clever malingerer and thief, slyly steal a slice of bacon when Perrault's back was turned, he duplicated the performance the following day, getting away with the whole chunk. A great uproar was raised, but he was unsuspected; while Dub, an awkward blunderer who was always getting caught, was punished for Buck's misdeed.

His muscles became hard as iron, and he grew callous to all ordinary pain. He achieved an internal as well as external economy. He could eat anything, no matter how loathsome or indigestible; and, once eaten, the juices of his stomach extracted the last least particle of nutriment; and his blood carried it to the farthest reaches of his body, building it into the toughest and stoutest of tissues. Sight and scent became remarkably keen, while his hearing developed such acuteness that in his sleep he heard the faintest sound and knew whether it heralded peace or peril. He learned to bite the ice out with his teeth when it collected between his toes; and when he was thirsty and there was a thick scum of ice over the water hole, he would break it by rearing and striking it with stiff fore legs. His most conspicuous trait was an ability to scent the wind and forecast it a night in advance.