"Real lifeworld communication by living agents cannot be depicted by mathematical equations because communicating living agents do not behave mechanistically and the syntactical structure of natural codes does not represent its meaning, which in most cases is not available in the superficial but in the hidden deep grammar. In such outdated concepts a natural code like the genetic code is reduced to the sum of its measurable and superficial attributes which can be computed in a digital and algorithm-based procedure."


So, ok, I'll jump in. When I read this, I thought, "well, yes, microRNAs can be considered 'nurture', although they can also be inherited" and did a quick search to see if this was a unique thought. Of course, it is not


"While the eukaryotic genome is the same throughout all somatic cells in an organism, there are specific structures and functions that discern one type of cell from another. These differences are due to the cell’s unique gene expression patterns that are determined during cellular differentiation. Interestingly, these cell-specific gene expression patterns can be affected by an organism’s environment throughout its lifetime leading to phenotypical changes that have the potential of altering risk of some diseases. Both cell-specific gene expression signatures and environment mediated changes in expression patterns can be explained by a complex network of modifications to the DNA, histone proteins and degree of DNA packaging called epigenetic marks. Several areas of research have formed to study these epigenetic modifications, including DNA methylation, histone modifications, chromatin remodeling and microRNA (miRNA). The original definition of epigenetics incorporates inheritable but reversible phenomena that affect gene expression without altering base pairs. Even though not all of the above listed epigenetic traits have demonstrated heritability, they can all alter gene transcription without modification to the underlying genetic sequence. Because these epigenetic patterns can also be affected by an organism’s environment, they serve as an important bridge between life experiences and phenotypes. Epigenetic patterns may change throughout one’s lifespan, by an early life experience, environmental exposure or nutritional status. Epigenetic signatures influenced by the environment may determine our appearance, behavior, stress response, disease susceptibility, and even longevity. The interaction between types of epigenetic modifications in response to environmental factors and how environmental cues affect epigenetic patterns will further elucidate how gene transcription can be affectively altered." (Tammen SA et al. Epigenetics: The link between nature and nurture. Molecular Aspects of Medicine. 2013; 34:753-764)


So there is randomness there, but also some predictability. I'm sure that math would be able to describe transcriptional variations based on environmental conditions, at least by presenting probabilities of different outcomes. So I went looking again. It can.


"Presently, a system-theoretic approach was presented to analyze and quantitative modeling of a generic miRNA pathway, which can be implemented deterministically and stochastically. Our results show that the inferred dynamic properties obtained from the mathematical models of the miRNA pathway are well consistent with previous experimental observations." (Wang X et al. Toward a system-level understanding of microRNA pathway via mathematical modeling. Biosystems. 2010; 100:31-38)


Looking at complexity, activities on a group level can be accurately modeled by very simple equations (wide database on this one). So inherently, I side with Cryberg (fwiw) and think Randy's definition of Nature is too limited; we are just bits of the universe and prior supernovas, after all (apologies to Carl Sagan). And the math has led us to dark matter and dark energy, and the understanding that there will be no "big crunch." So while math may not embody nature (though it likely does), it certainly can be used to describe it, both on a micro and macro scale.


S

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