Sherbourne Le Souef, a director of Sydney's Taronga Zoological Park during the first part of the twentieth century, utilized his observations of nonhuman animals living in captivity to write on the "actions, reactions and traits common to [humans] and animals" (Le Souef, 1930, p. 598). Le Souef's writings reflect his search beyond the human will for "the genesis of man's actions and reactions" (p. 598) and his appreciation of evolutionary theory where the idea of hierarchy was maintained. Similar to William T. Hornaday, a director of the zoological gardens in New York, Le Souef sought the moral improvement of zoo audiences through encouraging observation of nonhuman animals. More broadly, he argued for the relevance of his own observations to the general progress of the peoples of the new world. This paper identifies how notions of animal behavior were understood to indicate social, cultural, spiritual, and species hierarchies.