 Although explicit cybernetic accounts of biological teleology have fallen out of favor, other organizational approaches to biological function have had a recent resurgence in the function literature. These organizational, or systems-theoretic, approaches often build upon early cybernetic accounts or aim to extend Maturana and Varela’s (1980) influential notion of autopoiesis, which refers to the self-organizing, self-maintaining characteristic of living systems (see the entry on  Embodied Cognition  for further description). These accounts identify the function of a biological trait through an analysis of the role the trait plays within an organized system in contributing to both its own persistence and the persistence of the system as a whole (Schlosser 1998; McLaughlin 2001; Mossio et al. 2009; Saborido et al. 2011; Moreno &amp; Mossio 2015). Although they differ in their details, organizational approaches to biological function generally agree that a trait token T has a function F when the performance of F by T contributes to the maintenance of the complex organization of the system, which in turn results in T’s continued existence. For example, the heart has the function to pump blood, according to these accounts, because it contributes to the maintenance of the entire organism by causing the blood to circulate, which facilitates the circulation of oxygen and nutrients. At the same time, this circulation is also responsible in part for the persistence of the heart itself, since the heart also benefits directly from this function (i.e., the cardiac cells receive the oxygen and nutrients necessary for their survival). 