Ok … found these words … they seem to encapsulate what we've collectively said however, I personally disagree that
all genetic mutations are purely random, because there is clear recent evidence to the contrary. This aspect is important when considering the minimal subset of environmental conditions we think are necessary for the emergence of exo-life.
I also find that these words (and the concept), also assumes we know intimately beforehand, what is required for the survival of the organism and then conclude that if an organism survives over the long haul, it must therefore possess the survival characteristics we assumed in the first place.
In Darwin's day, this was obvious at the macro functional/feature level of a species. However, in modern times, we have discovered way more about the complexity of genetic interactions, their influences at the micro (DNA) level and what causes mutations. (Molecular Genetics).
For me, a large proportion of the diversity we see amongst life-forms, may be more a characteristic of not necessarily survival associated, but none-the-less, environmentally induced mutations. Perhaps its my own lack of knowledge, but I'm not sure Darwinian Evolution Theory addresses the reasons for propagation of what could easily be mutationally induced, non-essential characteristics (??)
As a result, I feel that there are other processes which run in parallel, (ie: not necessarily contrary to Darwinian Evolution), which have clearly operated since life emerged from the chaos.
What does this perspective tell us about the chances of life emerging elsewhere ? Frankly, I have no supportable ideas, other than I can see this thinking
does support the concept that diversity, (which includes the superset encompassing the 'null' no-life outcome), may be way more susceptible to the
initial environmental conditions from which life originally emerged
once, than perhaps we can envisage. It also lends legitimacy to the possibility of extreme rarity of more than once instance of it.
There is a Hypothesis called 'Differential Susceptibility' which speculates that individuals vary in the degree they are affected by experiences, or qualities of the environment they are exposed to. These characteristics are then linked to susceptibility factors which can range from emotional states like temperamental anxiousness all the way 'down' to the protein/DNA level. (Mind you, it remains as a 'considered' hypothesis
).
Having made these statements, I find that the following words, do fairly describe the classical biological definitions pertaining to the role randomness plays in classical, traditional, Darwinian Evolution Theory:
Quote:
Randomness in biology:
The modern evolutionary synthesis ascribes the observed diversity of life to natural selection, in which some random genetic mutations are retained in the gene pool due to the non-random improved chance for survival and reproduction that those mutated genes confer on individuals who possess them.
The characteristics of an organism arise to some extent deterministically (e.g., under the influence of genes and the environment) and to some extent randomly. For example, the density of freckles that appear on a person's skin is controlled by genes and exposure to light; whereas the exact location of individual freckles seems to be random.
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Cheers
