Chemical Automata

I first came across Chemoton (Chemical Automaton) Theory a few months ago when reading a paper entitledSoftware Replica of Minimal Living Processes, and ever since it has been an inspiration.  At the time, I was trying to figure out how I could possibly build a system that spanned the range of complexity from Chemistry to a minimal Biology.  I was going off of Walter Fontana’s incredible Algorithmic Chemistry work, trying to find a way that his Lambda Calculus approach could become spatial.  It was Ganti’s Chemoton Theory that finally got me there.

Incredibly, the publication of Chemoton Theory in 1971 and subsequent refinement in the early 70′s was practically simultaneous with Maturana and Varela’s Autopoiesis work and Manfred Eigen’s RNA Hypercycles Theory.  Chemoton Theory, unlike Autopoiesis, is based on a very precise model, though simplified, model of chemistry.  In recent years, Ganti has even gone so far as to detail what actual chemical reactions could possibly realize a Chemoton.  Autopoiesis provides no such precision although the work of Pier Luigi Luisi has taken it much further in that direction.

A Chemoton is a network of 3 autocatalytic cycles: the metabolic (energy), template replication (information), and membrane (boundary/dynamics).  Together, they model a minimal living entity as they meet Ganti’s basic criteria of a living system:

• it’s an individual unit
• it performs metabolism
• it’s inherently stable despite constant transformation
• it has an information subsystem that programs the whole
• it’s processes are regulated and controlled

I’m, of course, leaving out a lot of the details so this may not seem like a full definition of a living system.  For the complete explanation, see Ganti’s paper Biogenesis Itself or even better his book The Principles of Life.

What’s most intriguing about the Chemoton from a worldmaking standpoint is it’s fluid nature.  Chemical reactions function best in a fluid environment where spatiality is subsumed by chemical concentrations and statistical tendencies.  There doesn’t need to be a strict spatial ordering for Chemotons to function, just the appropriate chemical concentrations bounded inside a membrane.

Chemoton Theory shows in precise detail how to go from chemistry to a minimal biological unit, but it doesn’t say much about the structure of the membrane or how networks of membranes might form into more complex biological structures.  In the end of Chemoton Theory vol. 1, Ganti speculates about how computers might be built from such objects, but doesn’t link it to Morphogenesis or Topobiology.

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