A Pragmatist-Artifactualist view of experimental model organisms: the case of epigenetic inheritance

Abstract Model organisms have long occupied a central place in the life sciences, driving major discoveries and stabilizing knowledge about biological mechanisms conserved across taxa. However, their dominance has often eclipsed experimental model organisms—specimens chosen for their capacity to illuminate local hypotheses, usually associated with organism-specific features. This paper advances a twofold argument. First, I contend that overreliance on model organisms constrains the generation of novel hypotheses and narrows the conceptual landscape of biological inquiry. Using epigenetic inheritance as a case study, I show how this focus has systematically marginalized forms of inheritance that depart from conventional assumptions (i.e., germline/material overlap and transgenerational stability). Here, I concentrate on external intergenerational epigenetic inheritance. Second, I argue that merely vindicating the use of experimental model organisms is insufficient without examining the philosophical assumptions that structure their epistemic function. Specifically, I demonstrate that the representationalist conception—models as surrogates for target systems—permeates the conceptualization of experimental model organisms through the idea of representational function, thereby reinforcing framed trajectory-dependent inquiry. This representationalist conceptualization undermines the capacity of experimental model organisms to support framing exploratory inquiry oriented to test conceptually disruptive ideas, such as external intergenerational epigenetic inheritance. To overcome this limitation, I develop a Pragmatist–Artifactualist framework that reconceptualizes the epistemic role of experimental model organisms and restores their potential to expand the boundaries of biological understanding.