Evolution
is a theory fraught with difficulties – so much so that I'm
genuinely surprised that people still take it seriously. I'm not
talking about answers we don't have – like, a plausible explanation
for the origin of the first common ancestor or not finding any
fossils for the “innumerable” transitional species Darwin
understood must have existed if his theory were true; I'm talking
about things that we do know, scientifically, that make evolution
impossible.
Let me
give you a thumbnail sketch of how the theory is supposed to work.
Some people conflate evolution with natural selection. Natural
selection is the opposite of evolution. If you start with a
population of light and dark moths, and birds continuously eat (i.e.
“select”) the light moths, you will eventually have a population
of only dark moths. Natural selection can only “select” from
traits already present in the population. You cannot add new colors
by continuously removing colors no matter how long it continues. For
evolution to be possible, you have to add new traits to a population.
To turn a dinosaur into a bird, for example, you would have to add
feathers. Get it? Natural selection is not a mechanism that can add
new features to a population.
The
only candidate for a mechanism that adds new features to a population
is genetic mutation. Mutations are an observed phenomenon where
duplication errors in the DNA of a the parent creature are passed
along to its offspring. Most of these errors are neutral and are not
expressed in the offspring. Even though they aren't expressed,
though, they still exist in the genome. Sometimes, the mutations are
expressed and can be harmful or fatal to the host. On very rare
occasions, a mutation can convey a benefit to its host.
One
example of an observed, beneficial mutation is tusk-less elephants.
Ivory poachers will shoot elephants for their tusks. However, due to
a genetic mutation, some elephants are born without tusks and so
poachers won't shoot them. This is a benefit to the elephant. These
elephants tend to live longer and pass the “tusk-less” mutation
onto its offspring. In recent years, there has been a noticeable
surge in the numbers of elephants born without tusks. But this type
of mutation is not the trait-adding kind of mutation that could make
evolution possible. Elephants being born without tusks does not
explain how dinosaurs could acquire feathers.
The
supposed first ancestor did not have feathers, hair, skin, scales,
bones, blood, eyes, or organs of any kind. To turn a molecule into a
man would require a billions of years long parade of novel features
being added generation after generation. If evolution has happened,
we should have many examples of observed, trait-adding mutations. We
don't. In all my years of asking for examples of novel features
appearing in a species, I continuously hear the same 3-4 questionable
examples.
Trait-adding
mutations are either astonishingly scare or non-existent.
Evolutionists, however, are not deterred by the glaring lack of
examples. Time is the hero of their fairy tale. In a 4 billion year
old world, a new feature every million years or so is enough to
rescue their theory. I'll tell you why it doesn't.
Are we
agreed that trait-adding mutations are infrequent? OK. How often
can we agree that they happen? Is it once every hundred mutations?
Surely, it's not that often. I don't think it happens at all but,
for the sake of argument, I could say it's more like 1 in 10,000 or
even 1 in 100,000. Actually, in a moment you'll see why higher
numbers are worse for evolution but I'm going to be very, very
generous and say it's 1 in 1,000. Now, let's look at some math.
If 1
in every 1,000 mutations is a beneficial, trait-adding mutation for
the host, then for the host to inherit 2 beneficial mutations means
there will have been 1,000,000 neutral or harmful mutations (1,000 x
1,000). To inherit only 3 means there will have been 1,000,000,000
neutral or harmful mutations in the genome (1,000 x 1,000 x 1,000).
Can you see where this is going? The genome is deteriorating 1,000
times faster than it is improving. To inherit even a handful of
successful mutations comes at the great expense of billions and
billions of unsuccessful mutations. How many successful mutations
would it take to turn a molecule into a man? How long could such a
wasteful process continue before the entire genome becomes too
corrupted to sustain life? Remember, this is assuming 1 beneficial
mutation in every 1,000. If it were 1 in 10,000, then 2 successful
mutations comes with the burden of 100,000,000 other mutations!
In
1995, A.S. Kondrashov published a paper in the Journal
of Theoretical Biology where
he discussed contamination of the genome by very slightly deleterious
mutations. Over time, the ratio of harmful mutations to good
mutations should become unbearable and he says, “This
paradox cannot be resolved by invoking beneficial mutations or
environmental fluctuations.”
In
the title, he asks, “Why
have we not died 100 times over?”
Can you see now the problem that he saw? Any small success a
mutation might mean for a species comes with many more mutations that
should eventually kill it. It's a numbers game... and evolution is
losing!
1 comment:
Some people conflate evolution with natural selection. Natural selection is the opposite of evolution. If you start with a population of light and dark moths, and birds continuously eat (i.e. “select”) the light moths, you will eventually have a population of only dark moths.
Given that "evolution" is defined as a change in the frequency of inheritable traits in a population over time, natural selection is obviously not the opposite of evolution. In any case, it is obfuscation rather than explanation to treat natural selection and mutation as though they were not simultaneous and interacting phenomena.
n 1995, A.S. Kondrashov published a paper in the Journal of Theoretical Biology where he discussed contamination of the genome by very slightly deleterious mutations. Over time, the ratio of harmful mutations to good mutations should become unbearable and he says, “This paradox cannot be resolved by invoking beneficial mutations or environmental fluctuations.” In the title, he asks, "Why have we not died 100 times over?"
Having dismissed two possible solutions to the paradox, he goes on to consider some others, including "soft selection and synergistic epistasis among very slightly deleterious mutations."
Soft selection is basically natural selection grading on a curve -- the fittest individuals in a population pass on their genes, rather than only those above some hard minimum level of fitness. Synergistic epistasis means that [a] genes interact in ways that can't be predicted simply from their individual effects, and [b] in the case of mildly deleterious mutations, these joint effects often mitigate the harmful effects of the individual mutations (this is an observed effect in genetics).
Kondrashov has also written on the effects of sexual reproduction in mitigating the effects of accumulated mildly deleterious genes -- the recombination of genes during sex improves the weeding out of harmful genes.
The paper cited in your post noted that these effects arise when population sizes (individuals in a species) are smaller than than the number of base pairs in the species' genome (the number of mutations, of course, tends to go up with the number of base pairs available to mutate, while the effects of selection are greater with greater population size). This is probably relevant to why asexual reproduction is more common in microscopic forms with small genomes and immense populations, while most familiar species reproduce sexually.
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