The concepts of function and semiosis (sign processes) are intertwined. Both are teleological concepts in the sense of being determined with respect to an end (or other than itself)—a specifically correlated absent content. Although it is unclear whether these two properties of living processes (function and semiosis) are exactly coextensive, it is clear that although time-asymmetrical, irreversible physical processes are found in the prebiotic physicochemical world; teleological processes that are specially organized with respect to specific ends or referents are unique to living processes.
If we think of a function as a process organized around an implicitly represented end, then these two classes of phenomena must be considered entirely coextensive. …
…
Neo-Darwinian biology as practiced all over the world has prescinded (i.e., abstracted from necessary contextual support) an asemiotic conception of life as mere molecular chemistry, and yet at the same time it is dependent on unanalyzed semiotic assumptions. The reason why this is not felt as a problem is that biology compensates for the excluded semiosis by introducing a plethora of implicitly semiotic terms like “information,” “adaptation,” “signal,” “cue,” “code,” “messenger,” “fidelity,” and “cross talk.” These uses are seldom well defined and are often applied in an allegedly metaphoric way, with the implicit assumption that they can be reduced to mere chemical accounts if necessary.
…
It is the aim of biosemiotics to make explicit those assumptions that are imported into biology by such unanalyzed teleological concepts as “function,” “information,” “code,” “signal,” and “cue” and to provide a theoretical grounding for these concepts. …
…
Functions are not only the output of evolutionary history; rather, functionality is the prerequisite for organic evolution. For instance, autocells do not in all cases have an evolutionary history, but they do have functions. Evolution presupposes function rather than vice versa. Natural selection cannot be defined except with respect to a bounded, self-maintaining, and self-reproducing dynamical unit system. A discrete system with these properties must therefore be constituted by component materials and dynamical processes that reciprocally generate each other as well as their collective organization. The critical features and dynamical actions of these components exemplify Kant’s criteria for possessing intrinsic telos and are thus functional. The possibility of evolution derives from the fact that functions, because they can be realized multiple number of times, can coopt any incidental physicochemical properties of the substrates they utilize. Likewise, semiosis can coopt any incidental feature exhibited by functional processes or their properties.
Kalevi Kull et al., Theses on Biosemiotics: Prolegomena to a Theoretical Biology
