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Egr2 genes, activating β-promoter and LH secretion, whereas high pulses activate
the Nab repressor genes that suppress LH synthesis ( Lawson et al., 2007 ).
The processing of the stimuli in the CNS generates the epigenetic information for
signal cascades that control and regulate the expression of nonhousekeeping (sys-
temic) genes and individual development in animals. The evolution of the neural pro-
cessing in the CNS was a prerequisite for the increased morphological complexity
that characterized it.
The role of neural processing as a source of epigenetic information implies that
it is intended to figure out an adaptive response to an environmental challenge. It
tends to prevent, resist, or manage the anticipated harmful effects of environmental
actions/agents. This assertion may raise concerns on the teleological implications of
neural processing, because the words “intention” and “purpose” in everyday speech
invoke consciousness. However, despite whatever philosophical implication, it is
commonplace in scientific literature to speak of the purpose of animals, especially
when describing animal behavior. A sea gull's dive has as clear a purpose as that of
an eagle.
It may be argued that one cannot attribute intentions and purposes to the neural
processing taking place at electrical and chemical levels. But bear in mind, human
consciousness also results from the processes taking place at these “low” levels (see
page 79, Epigenetic Information and Signal Cascades ).
The Antientropic Demon and the Advent of Cambrian Biota—
Fine-Tuning Gene Expression
Multicellular animals are believed to have appeared between 110 and 60 million
years before the Cambrian period. By any account, this is a long period of evolution-
ary stasis that needs an explanation. Common sense says that a barrier existed at the
time and time was needed to break through it. In 1992, Steven M. Stanley came up
with an idea that the neuron evolution might have triggered the Cambrian explosion.
Insightful as it is, in hindsight, the idea was not accurate. Ediacaran eumetazoans of
the cnidarian sort existed at least 30 million years before the Cambrian phenomenon.
As mentioned earlier, the Cambrian diversification coincides not with the neuron but
with the transition to the centralization of the nervous system. Cnidarians that did not
venture out were evolutionary losers.
Why might the centralization of the nervous system have been such an indispen-
sable innovation for the further evolution of the animal world? The centralization
amplified the computational capabilities of the nervous system required for evolv-
ing, erecting, and maintaining more complex structures in the Cambrian biota. The
acquisition by the centralized control system of the craftsmanship to monitor, work
out instructions, and transmit them for restoring the normal state down to the cell
level, including the ability to reproduce the organism, enabled the major transition
to the higher stage of structural and functional complexity of the Cambrian biota.
The centralization of the nervous system provided animals with an unprecedented
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