springer | Most contemporary evolutionary biologists
consider perception, cognition, and communication just like any other
adaptation to the environmental selection pressures. A biosemiotic
approach adds an unexpected turn to this Neo-Darwinian logic and focuses
not so much on the evolution of semiosis as it does on the semiosis of evolution.
What is meant here, is that evolutionary forces are themselves
semiotically constrained and contextualized. The effect of environmental
conditions is always mediated by the responses of organisms, who select
their developmental pathways and actions based on heritable or
memorized past experience and a variety of external and internal
signals. In particular, recognition and categorization of objects,
learning, and communication (both intraspecific and interspecific) can
change the evolutionary fate of lineages. Semiotic selection, an effect
of choice upon other species (Maran and Kleisner 2010), active habitat preference (Lindholm 2015), making use of and reinterpreting earlier semiotic structures – known as semiotic co-option (Kleisner 2015), and semiotic scaffolding (Hoffmeyer 2015; Kull 2015), are some further means by which semiosis makes evolution happen.
Semiotic
processes are easily recognized in animals that communicate and learn,
but it is difficult to find directly analogous processes in organisms
without nerves and brains. Molecular biologists are used to talk about
information transfer via cell-to-cell communication, DNA replication,
RNA or protein synthesis, and signal transduction cascades within cells.
However, these informational processes are difficult to compare with
perception-related sign processes in animals because information
requires interpretation by some agency, and it is not clear where the
agency in cells is. In bacterial cells, all molecular processes appear
deterministic, with every signal, such as the presence of a nutrient or
toxin, launching a pre-defined cascade of responses targeted at
confronting new conditions. These processes lack an element of learning
during the bacterial life span, and thus cannot be compared directly
with complex animal and human semiosis, where individual learning plays a
decisive role.
The determinism of the
molecular clockwork was summarized in the dogma that genes determine the
phenotype and not the other way around. As a result, the Modern
Synthesis (MS) theory presented evolution as a mechanical process that
starts with blind random variation of the genome, and ends with
automatic selection of the fittest phenotypes. Although this theory may
explain quantitative changes in already existing features, it certainly
cannot describe the emergence of new organs or signaling pathways. The
main deficiency of such explanations is that the exact correspondence
between genotypes and phenotypes is postulated a priori. In other words,
MS was built like Euclidean geometry, where questioning the
foundational axioms will make the whole system fall, like a house of
cards.
The discipline of biosemiotics has generated a new platform for explaining biological evolution. It considers that evolution is semiosis,
a process of continuous interpretation and re-interpretation of
hereditary signs alongside other signs that originate in the environment
or the body.
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