In the year 1966 the writer Primo Levi publishes the tales' collection Storie naturali (Natural Stories) under the pseudonym Damiano Malabaila. At first reading, the volume seems quite far from the testimonial subjects of his most famous works and the unexpected presence of irony appears to contrast with the dramatic tones of Se questo é un uomo, Se non ora, quando (If this is a man, If not, when). However, this humour emerges from the attitude adopted by the chemist writer, interested in the contradictions of life, the writer that, recognised by himself, declares to be literally a voyeur; an observer, an etologist in today's words. This paper proposes an analysis of this work that could be categorised within the sphere of science fiction, considering the topics, the antecedents and sources, literary as well as scientific, and the linguistic value, specially the oral tone of the stories. [ABSTRACT FROM AUTHOR]