Page 52 - The Origin of Life and the Universe - International Conference 2016

The Origin of Life and the Universe
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The last category is that of macro-
evolution. And be very careful here
because this is where equivocation
takes place most often. Macroevolution
refers to a series of naturalistic process-
es. It’s occurring over long stretches
of time, that account for all of life’s
history, forms, and complexity resulting
from descent with modification under
pressures of natural selection, acting
upon unguided changes in population
genetics, in a contingent and non-
teleological fashion. It is supposed
that macroevolution involves multiple
different mechanisms for achieving
its end goals.
One mechanism is that of genome
duplication. But genome duplication
is simply replicating a genome that you already have, you now have twice as
much that genome. And it provides no new information, just greater amounts
of DNA. In current observation, genome duplication in human cells is most
frequently associated with cancer. And so this type of genetic increase in in-
formation is actually deleterious. Similarly with translocation or jumping
genes for some segments of DNA can be transferred and copied into new po-
sitions in the chromosome or different positions in the genome, this type of
mechanism can shuffle DNA, information within a genome and replicate
some portions of the DNA, it’s not providing new DNA. And in current ob-
servations these two is associated with human diseases.
Horizontal gene transfer, although it occurs by viral mediated mecha-
nisms, it is not the same as that occurs in single cellular organisms. For
horizontal gene transfer, to even take a hold in a human population, it ab-
solutely must occur in the germ line, in the egg of the female or the sperm
of the male. Two other mechanisms, co-option or symbiogenesis are often
appealed to as well, to account for some of the diversity. But each of
these has its own hurdle.