I had an interesting discussion with biologist John Torday yesterday about mitosis - cell division. Growth is such a fundamental category in biology that it is easy to draw assumptions about it: the reason why cells divide is to reach out further into the environment; the reason is to survive; the reason is so that the cells differentiate; the reason is to generate redundancy; the reason is because "life is growth"... etc. But if you were sitting on the boundary of cell, why would you decide to split and divide so that all of sudden there are two cell boundaries?
Part of the answer to this is that you might decide to split because the boundary you are sitting on is unstable. It might be unstable because the environment in which the cell is attempting to survive in is uncertain or ambiguous. But why then would division contribute to a better way of managing that ambiguity or instability? Wouldn't it just amplify it?
This is the critical question, and the answer to it leads to a new way of thinking about growth. Because division doesn't create another boundary; it creates a relation between two cells. Growth is the conversion of a single boundary into a communicative process which provides new dimensions of variation, stability and observation: each cell becomes an observer and communicator with other cells. Increased variety equips the two-cell system with better equipment for managing the complex of the environment. But only so far: more division is necessary, so new cells further divide, further increasing the variety.
This increased variation has a particularly important property and advantage over a single cell: the two-cell communicative relationship provides for the construction of an anticipatory system. The cellular communication dynamics give rise to a higher-order selection mechanism which steers the cellular communication. The growth of this mechanism also suggests that at some point, there is a limit to the need for further sub-division. This limit is real, and known as the Hayflick limit: human cells can only divide and replicate between 40 to 60 times (Hayflick limit - Wikipedia)
Reflecting on this, the two key points that:
- growth through division is the creation of relations and communication
- growth is limited
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