In the 20(th) Century the medieval Bestiary experienced a new impetus in Latin America. Through their descriptions, the authors offer a new vision of the mentioned animals. From the 60s, we can find the genre in very short texts where the narrative intention is mixed with the essay's characteristics. With the use of irony and related strategies, the values and the function of the Bestiary were inverted. As a result, the genre experienced a radical change. Los animales prodigiosos of Rene Aviles Fabila is among the works that belong to this trend. In this article I propose to analyze this book as the last link in the genre's evolution, emphasizing on the evolution of Bestiary in the 20(th) Century, its intertextual relations and its links to Aviles' poetics.