rationalskepticism.org

I have only recently encountered biosemiotics in the process of my hermeneutical research. Right now, I am reading "Theses on Biosemiotics: Prolegomena to a Theoretical Biology" (Kull et al. 2009). Thesis 17 (e) (Biological Theory 4(2) 2009, p.117) is given as "Differentiation of a sign vehicle from the dynamics of the reciprocal form-generating process. A sign vehicle must be insulated from the dynamics that it constrains and that is responsible for generating a repetition of this process."
I am unclear as to why this would be so? Would a sign vehicle by its very nature have some degree of reciprocity with the dynamics it enables?

Thanks very much for any clarity on this point.