Meanwhile, London continues to develop the idea of the existence of a kind of species memory, which allows Buck to tap into the experiences of his wild ancestors. This species memory shows itself not only in the instincts that life in the wild has awakened in Buck but also in the visions that Buck begins to have. London makes Buck something of a mystic, able to look into the ancient past, before civi-lization appeared on the earth. There, he has visions of primeval man, “all but naked . . . afraid of the darkness . . . [with] a quick alertness as of one who lived in perpetual fear of things seen and unseen.” With such visions, London suggests that while Buck’s life as a pet, in sunny California, may have been soft and overcivilized, the relationship between man and canine stretches back into the primitive world, when humans needed dogs to protect them from the terrors of the night. This idea of an ancient, natural relationship between men and dogs is developed further when Buck acquires the ultimate good master in John Thornton.