Abstract (em inglês) This article presents a critical reflection on Karl Popper’s famous “black swan” metaphor, widely used to illustrate the principle of scientific falsifiability. Through a biological and taxonomic analysis, it argues that the metaphor relies on disguised induction and an imprecise definition of the term “swan. ” The black swan (Cygnus atratus) and the white swan (Cygnus olor) belong to distinct species, which undermines the validity of Popper’s proposed refutation. The critique extends to other zoological examples — such as herons, parrots, parakeets, macaws, cats, and dogs — to demonstrate how popular names often group different species under a single label, leading to conceptual confusion. The article concludes that the strength of scientific refutation depends on the precision of the terms used, and that poorly formulated metaphors can weaken scientific reasoning by conflating linguistic adjustments with empirical discoveries. Keywords: Philosophy of science, Falsifiability, Induction, Scientific metaphors, Taxonomy, Black swan, Karl Popper, Scientific language, Biological species, Conceptual precision.