The Origins of Life itselfWhat do we learn about the origins of life from its information-based interpretation ?
One of the most difficult (and as yet unanswered) problems is that even a minimal life form (as simple as possible) seems to be implausibly complicated. That is, for any such thing to emerge spontaneously (at random) from interactions among basic molecular components, under purely pre-life rules, seems impossible. This problem is termed the sequence paradox and is developed as an argument using information thinking as well as basic biochemistry on our page here.
Stuart Kauffman provides a good introduction to efforts made to understand the origin of life (here).
Many of the proposed mechanisms seem to fail in practice, becasue of biochemical difficulties and in particular an apparent bottle-neck in trasmitting the information necessary to construct a complex chemical system, reliably and repeatedly.
Understanding what life is, in the most fundamental sense possible, is a good starting point for understanding how it arose originally. There are several, as yet unconfirmed, theories about the origin of life on earth, but what about more generally: how can it emerge independently of the earth? To answer this question, we must first establish what specifically and sufficiently constitutes life.
The first point is that all the life we know of, consists of a complex network of highly coordinated chemical reactions. If all the right chemicals are available, but they are not reacting, or not reacting in the right place at the right time, then, no life will be found. If there are not the necessary chemicals, the same will be true. The difference between the living and the dead is that the living constitute a particular set of reactions, organised into a particular configuration in space and time. A dead organism is also a network of chemical reactions, but these are different and less coordinated: they are the reactions of decay and chemical return to equilibrium with their surroundings. Indeed one defining feature of life is that it is out of chemical (and therefore energy) equilibrium with its environment, but then so is a star. There is no complex organisation of chemical reactions in a star (as we understand them) and their structure is maintained as an average of a very large number of random configurations and interactions among their component parts. Life is characterised by a surprising lack of randomness in configuration: it is a persistent pattern, which is the embodiment of information (formative information). At the other end of the scale, we could point to a crystal, which is highly organised (an ordered array of atoms), but is also static, not dynamic with reactions, and b) so well ordered as to be remarkably simple and therefore embodying remarkably little information. Somewhere between the ferocious reactivity of a star and the ordered timelessness of a crystal lattice, lies something very special: a balance between dynamism and retention of complex pattern. This is life.
Although it has been notoriously difficult to pin down precisely what it is that makes life so distinctive and remarkable, there is general agreement that it has to do with information. The unique informational narrative of living systems suggests that life may be characterised 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 organisational 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. One thing is certain, though. Life necessarily continually maintains and renews its informaiton-structure. This process, observed as self-repair and reproduction is termed autopoiesis: a unifying concept that is described here. Life would not exist without this capability.
Here is a fun description featured in the popular press (and YouTube).
Also, we like this website: Exploring Life's Origins - it's a great graphical explanations of pre-biotic & RNA world theories. Here is a good introductory article in The Scientist Magazine that is still rather up-to-date. We Have more pages in preparation for this subject area; it is just taking a bit of time! For now, we recommend the recent works of Christoph Adami and also Sara Walker and colleagues.
This Theme aims to:
- Develop an understanding of the origin of life (in general) using an information-based approach;
- Describe the development of life in terms of information and