components
are missing, or if the processes themselves are interrupted in some fashion,
then life ceases. For the very simplest life-forms, the replication process may
well be the ultimate end in itself. Thus, their fullest meaning of life
is to exist, and through that existence to cause more of their kind to exist.
We’re hard pressed to say that this is not also the basic meaning of life for
more complex species as well. The question of whether a meaning of life should
be attached to the grown organism or to its origin is examined in depth by
Richard Dawkins in The Selfish Gene. Actually, the question can be
extended to any aspect of the organism during its development. Beyond the
basics, a meaning of life will have to be found elsewhere than, for example, in
the need for the individual to exist and reproduce through a hosting organism.
Through DNA’s
blueprint facility, a construction pattern is passed from one generation to the
next. If the pattern is changed, then the new generation is different from the
old generation. This feature can be used to extract a history of sorts regarding
the changes among different generations of a species or between one species and
its precursor species. Specifically, relatively minute changes within certain
sections of the genome of a species when compared to similar sections in the
genome of a precursor species can give an indication of the time lapse since
the divergence of the two species. With an assignment of a value of good
to the quantity of a specific living entity (or collection of similar entities)
then it is indeed good for a particular common genome to propagate and bad if
it terminates. Continued propagation translates into more living material and
termination of propagation translates into less. This could be innocently
rendered as the purpose of living entities at its most basic level.
Once we move
beyond the simplest forms of life, purpose becomes a more abstract concept to
apply and to interpret. To some extent, the more simplistic purpose still
applies; we see at least the tinge of this logic applied in the highest and
most esoteric levels of sentient life. Through complex groups of people, for
example, evolutionary principles to a large extent play out just as they do
with simpler life forms. With such groups, however, the mechanisms of change
and selection are also more complex than those found for simple and/or single
organisms. But similarly, the social structures that are effected through the
grouping of individuals are largely about ensuring that they propagate to the
superiority of other similar structures at best, and at the very least survive
in the face of these other structures. However, it seems likely that this isn’t
the complete story of the interaction of complex groups, as we’ll consider a
little later on.
The principle of
evolution involves two distinct phases: first, the introduction of an organism
with new characteristics into an environment and second, the process of natural
selection through which the efficacy of the new organism, or, perhaps more
appropriately, its new characteristics within the environment are judged to be beneficial. Just what constitutes
beneficial will be considered in the following section. For the moment, in
considering the first of these phases, that is, the introduction of a new
organism into an environment, we find two generally accepted mechanisms for
change. Living organisms can be significantly altered in form through a change
process call mutation. A mutation is a
change in the base-pair sequencing within a DNA molecule. Any such change can
impact the subsequent production of proteins. This might result in the
production of altered proteins or changes in the operational instructions
regarding the amount, location and functional purpose of the proteins produced.
If the change occurs in the germ cells or zygote that are so central in the
earliest stages of reproduction and the mutation is not lethal, then the
resultant change will be propagated throughout the entire new individual. Genetic
variability is also introduced into organisms as a result of genetic recombination, also called chromosomal
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