what does the trick that Huck plays on Jim reveal about buck in his relationship with Jim

Huck tries to play a trick on Jim by leaving a curled up dead rattlesnake under Jim's blanket. But when Jim crawls into the bed he gets bitten in the ankle by the snake's mate. Huck kills the mate and sheepishly carries both snakes far away from the cave, embarrassed by the results of his behavior. Although Huck is a prankster, he really feels bad for putting Jim in danger.