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In interpreting The Pearl by John Steinbeck, it is important to be aware of Steinbeck's background and philosophies. One tremendous influence upon the author was his close association with Edward F. Ricketts, a marine biologist, who helped Steinbeck develop general theories about the interrelationship of all life. With what he learned of the biological relationships, Steinbeck added socialism to form his literary vision:
man should act in concert with others to live happily and for the good of all creation. Essentially Steinbeck's theory was a biological twist to the growing movement of the 1930s "Proletarian Realism." (enotes)
Steinbeck, then, groups human society; his characters begin in harmony with nature but then evil, such as materialism and the greed in The Pearl, upsets this order. For instance, in Part I, Steinbeck writes,
This doctor was of a race which for nearly four hundred years had beaten and starved and robed and despised Kino's race, and frightened it too, so that the indigene cam humbly to the door.
Thus, Kino and Juana, the "indigene," become more like hunted animals than people. Steinbeck's animal imagery also serves to symbolize that Kino and his wife are part of the natural world from which they deviate after finding the great pearl. This disharmony of man from nature is what effects conflict.
Remembering that Steinbeck's novella is an allegory also allows the reader to understand that the animals are symbolic of several relationships established with the characters. One of these relationships is that of predator and prey. When Kino dives for the great pearl, he observes the small fish fleeing a greater school of fish, a symbolic representation of the class conflict which develops in the narrative. Another relationship is that of the upperclass who view the Indians as mere animals. Ironically, however, in their greed, the trackers "whine like dogs" on a trail, and they steal through the night like foxes.
As Kino becomes more and more desperate to sell the pearl so that he can have the material things that he beliees will make his family more worthy, he becomes corrupted, hissing at Juana like a snake and "Juana stared at him with wide, unfrightened eyes like a sheep before the butcher." Of course, this description of Juana also serves to symbolize the end to which Kino's family comes.
Clearly, as an allegory, animal imagery is vital to Steinbeck's narrative as it establishes the relationships of the characters. When, for instance, Kino first comes to the doctor, the doctor asks, "Am I a veternarian?" Then, too, this animal imagery points to the disharmony that Kino and his family encounter when they value a material thing over the spiritual. For, humans are but one animal in life's web, and they must remain in harmony with nature else peace--La Paz--is disturbed. This is why Kino and Juana finally throw back the pearl to the ocean where it belongs; they must reestablish the natural order.