Biology Reference
In-Depth Information
However, as complexity grows, so does fragility. The organization of basic
autonomy, just by itself, does not solve the problem of preserving (for long-
term periods) the new complexity that it can generate, and therefore, neither
the problem of how this complexity could grow indefinitely. Of course, the
productive and reproductive dynamics of a scenario of basic autonomous systems
would allow the maintenance of certain level of complexity. But this - still
rudimentary - functional dynamics cannot ensure that the components (together
with their way of organization) remain unaltered for much longer than their
typical life spans (or the one of the whole organization), and the system faces a
bottleneck: as complexity rises, its preservation becomes more and more difficult.
Therefore, only those autonomous systems that developed specific mechanisms
to stabilize and retain the increasing structural and organizational complexity
with a fairly high degree of reliability could begin to unfold new, subsequent
levels of complexity and, furthermore, set up the first pillars to ensure their
long-term
maintenance.
Now, how to do that? As Szathmáry and Maynard-Smith (1997) have pointed
out, the way to preserve the specificity of an increasingly complex organization
is through what they call a mechanism of 'unlimited memory'. This mechanism
consists in linking the sequential structure of certain stable and self-replicating
components (to be more precise, the specific sequence of modular templates
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)
with the most complex structural-functional properties. This allows a 'storage'
or 'recording' of these complex (and highly specific) functions, which in turn
permits - if these material records become replicated - a reliable form of
reproduction (regardless of how complex the organization of the system is).
Thus, the requirement for the start of an unlimited hereditary memory is the
generation by (and integration within) the organization of autonomous systems
of suitable components for this storage.
There are two important aspects here. The first is that with the introduction of
these components the maintenance of the specific structure of the organization
changes: Instead of a mechanism in which the specific order of the system lies in
the dynamically dissipative maintenance of the whole organization, an important
part of such order is now frozen in the linear sequence of some components
(as this linear sequence will specify increasingly complex key catalytic functions
of the system, and therefore it will help to stabilize it). The second is that,
because such components have template capacities, they can transmit the specific
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A 'modular' molecule is a big structure made of a sequence (a small set) of subunits. In this component, the
global shape is a consequence of the particular order of the subunits. A molecule is considered a (catalytic)
template when its structure acts as blueprint, inducing the formation of copies of such structure. Although
modular templates are considerably complex molecules that hardly must have appeared before the evolution of
autonomous systems simple kinds of templates also probably played an important role in previous stages. For
instance, certain mineral surfaces would probably have played a role as catalysts in noncellular protometabolic
systems, or the very membrane in encapsulated systems.
