A significantly different approach to computational autopoiesis, termed Lattice Artificial Chemistry (LAC) has been recently pioneered in a series of studies by Ono and Ikegami.
LAC differs from the original model of Varela et al.  (and its direct descendants above) in adopting a coarse grained approach. In the original model, each lattice site can generally be occupied by at most one particle: it is fine-grained to the single molecule level. In LAC, by contrast, each single lattice site is permitted to host many particles, of many distinct molecular species.
Using this approach Ono and Ikegami have progressively reported:
Because LAC uses the coarse grained approach, direct comparisons with the fine-grained models are difficult. For example, when multiple cells are present in the same space, they normally share membranes, so that a population of cells exhibits a ``honeycomb'' structure. It is difficult to assess the degree of ``individuation'' on the part of single cells in this case (as multiple cells contribute to the maintenance of any given boundary).
The exhibition of selection at the cell level seems particularly significant . At this point, this is still limited to selection among a pre-designed variety of cell strains--there is nothing like a von Neumann style genetic architecture, or programmable constructor. Nonetheless, the LAC methodology clearly presents a very fruitful avenue of research.
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