Principles and Mechanisms of Biological Evolution - Molecular Theory of the Living Cell - page 485

active in the sense that organisms expend free energy to actively complexify their
internal states (e.g., basal metabolic rates of cells being greater than the minimum
levels needed for survival under given environmental conditions, EEG waves in
resting brains), which must have been the consequence of biological evolution,
leading to the following two equivalent statements:
The biological evolution results from the greater probability of survival of those organisms
that are capable of actively complexifying their internal states. (14.10)
Organisms that are capable of actively complexifying their internal states have the greater
probability of surviving complex environment. (14.11)
Underlying Statements 14.10 and 14.11 are the basic assumptions that there are
two kinds of complexities in nature (Sect. 5.2.3 ) , namely, “passive complexity” that
does not require any expenditure of free energy to be maintained (e.g., random
molecular motions in a volume of gas at equilibrium, the nucleotide sequences of
DNA in dead cells, random mutations) and “active complexity,” the complexity
that disappears when free energy supply is blocked (e.g., facilitated variations of
Kirschner and Gerhart (2005), the diversity of nucleotide sequences of DNA
resulting from recombination in living cells). Just as active transport at the micro-
scopic level is a unique biological phenomenon, not observed in nonliving systems,
so active complexity at the molecular level may be unique to living systems, not
observable in nonliving systems which can exhibit only passive complexity .I
maintain that most, if not all, of the discussions on complexity in computer science
and physics is about passive complexity , ignoring active complexity , just as
physicists focused on studying passive transport (e.g., diffusion of gases and
molecules) before active transport was discovered in living systems. An evidence
for active complexity may be provided by the so-called Huynen-van Nimwegen
exponent in Eq. 14.31 discussed in Sect. 14.7 .
Combining Statements 14.9, 14.10, and 14.11 allows us to assert the following
relation:

SLT + LRV + ACSRS = Biological Evolution (14.12)

where SLT stands for the Second Law of Thermodynamics (Sect. 2.1.4 ) ; LRV stands
for the Law of Requisite Variety (Sect. 5.3.2); and ACSRS is the acronym for Actively
Complexifying Self-Reproducing Systems exemplified by the living cell theoretically
represented by the Bhopalator (Sect. 10.1 ) . In a certain sense, Eq. 14.12 can be said to
embody two “selection rules” and a connector: SLT represents what may be referred
to as the “external selection rule” or the “external filter” that is imposed on organisms
from outside, ACSRS as the “internal selection rule” or the “internal filter” that
allows only those organisms to develop that obey the genetic instructions encoded in
DNA, and LRV that acts as the connector between the external world and the internal
world of organisms. Stated in words, Eq. 14.12 asserts that:
The Second Law of Thermodynamics and the Law of Requisite Variety are the
necessary and sufficient conditions for actively complexifying self-reproducing systems
to evolve. (14.13)