Theoretical origin of life; requires information (Introduction)

by David Turell , Sunday, March 08, 2020, 00:57 (1510 days ago) @ David Turell

A Paul Davies article:

https://royalsocietypublishing.org/doi/full/10.1098/rsif.2012.0869

"Abstract
Although it has been notoriously difficult to pin down precisely what is it that makes life so distinctive and remarkable, there is general agreement that its informational aspect is one key property, perhaps the key property. The unique informational narrative of living systems suggests that life may be characterized by context-dependent causal influences, and, in particular, that top-down (or downward) causation—where higher levels influence and constrain the dynamics of lower levels in organizational hierarchies—may be a major contributor to the hierarchal structure of living systems. Here, we propose that the emergence of life may correspond to a physical transition associated with a shift in the causal structure, where information gains direct and context-dependent causal efficacy over the matter in which it is instantiated. Such a transition may be akin to more traditional physical transitions (e.g. thermodynamic phase transitions), with the crucial distinction that determining which phase (non-life or life) a given system is in requires dynamical information and therefore can only be inferred by identifying causal architecture. We discuss some novel research directions based on this hypothesis, including potential measures of such a transition that may be amenable to laboratory study, and how the proposed mechanism corresponds to the onset of the unique mode of (algorithmic) information processing characteristic of living systems. (my bold)

***

"Although it is notoriously hard to identify precisely what makes life so distinctive and remarkable, there is general agreement that its informational aspect is one key property, and perhaps the key property. The manner in which information flows through and between cells and sub-cellular structures is quite unlike anything else observed in nature. If life is more than just complex chemistry, its unique informational management properties may be the crucial indicator of this distinction. Unfortunately, the way that information operates in biology is not easily characterized. While standard information-theoretic measures, such as Shannon information, have proved useful, biological information has an additional quality which may roughly be called ‘functionality’—or ‘contextuality’—that sets it apart from a collection of mere bits as characterized by its Shannon information content. The information content of DNA, for example, is usually defined by the Shannon (sequential) measure. However, the genome is only a small part of the story. DNA is not a blueprint for an organism:1 no information is actively processed by DNA alone. Rather, DNA is a (mostly) passive repository for transcription of stored data into RNA, some (but by no means all) of which goes on to be translated into proteins. The biologically relevant information stored in DNA therefore has very little to do with its specific chemical nature (beyond the fact that it is a digital linear polymer). The genetic material could just as easily be a different variety of nucleic acid (or a different molecule altogether), as recently experimentally confirmed. It is the functionality of the expressed RNAs and proteins—not the bits—that is biologically
important. (my bold)

***

"The central position of information in biology is not itself especially new or radical. What is often sidestepped, however, is the fact that in biological systems information is not merely a way to label states, but a property of the system. To be explicit, biological information is distinctive because it possesses a type of causal efficacy—it is the information that determines the current state and hence the dynamics (and therefore also the future state(s)). In this paper, we postulate that it is the transition to context-dependent causation—mediated by the onset of information control—that is the key defining characteristic of life."

Comment: Simple. The way life uses the information it has makes life exist from a bunch of active protein molecules all in the same soup. Not by chance.