It’s easy to mistake nature’s efficient processes of recycling
energy and nutrients for the eastern concept of ‘balance’. However, nature doesn’t
exist in a balance or ‘harmony’ - it is a constant battle resulting in
continual allelic flux. An war ongoing since the very first self-replicating
molecule, and this constant struggle for survival and proliferation isn’t just
happening on a species or an ecosystem level, it’s also happening both within
organisms and on a gene level. Most likely the layer cake goes even further; and
this struggle for replication is also occurring on a DNA level, including non-coding
regions.
Addressing balance through constant war
We see a snippet of the natural world during our short lives
and can mistakenly equate it to balance and order. In reality, what we are
seeing is just a tiny slice in time during the ongoing process of evolution.
Evolution is basically organisms adapting to or carving out new niches, filling
any gap that proves successful. This is what makes evolution so efficient at
recycling energy and creatively and non-directionally rerouting entropy. Nothing can actually slow entropy, not even extremely cold temperatures! It's not
just the bug eating the leaves, then the bird eating the bug, then the bird dying,
and the bacteria and fungi eating the bird, turning it into soil for the plant
to grow leaves. Bugs that avoid predation better than others are being selected
for, as they are slowly acquiring genetic elements that may change their
behaviour, or become more camouflaged, or produce noxious chemicals making them
unattractive to eat. In turn, birds that have genes or have mutations in genes,
for example that improve their eyesight keenness or depth of colour vision will
be able to keep up with the shifting allelic frequencies of their prey. When
the bird dies, the bacteria and fungi battle themselves, not just other
species, but their own progeny and daughter cells for colonisation priority and
therefore energy acquisition.
This is colloquially known as the Red Queen hypothesis, which
occurs on multiple fronts. Organisms are constantly co-evolving to one up each
other. Think the cheetah vs the gazelle. Over time, the cheetah has evolved a
specialised body to increase speed and acceleration to catch the gazelle, as
faster cheetahs catch gazelles and therefore survive to pass their genes on. In
turn, gazelles have evolved to be hyper-aware of predation, and have greater
stamina than the cheetah, as gazelles with greater stamina survive at a higher
rate than those with lower stamina. A local, within lifetime example of this is
if your adaptive immune system develops antibodies to surface markers of a
particular pathogen. Individuals within that population that invariably have
mutations in those surface markers will have greater fitness as they will now
be flying under the radar of your adaptive immune system detection. They will
therefore have greater opportunity and time to proliferate. This is similar to
how antibiotic resistance works; variation within the population caused by random
mutations eventually may eventually provide a selective advantage under
particular circumstances and will therefore proliferate. Antibiotic resistance
is of particular gravity, because the genes themselves are so useful at
increasing genetic fitness of bacteria that they been selected for on mobile
genetic elements, or plasmids. Many of these are transferred horizontally
between bacteria via mating, or via natural transformation.
Nothing is easy, and
everything is always changing. But make no mistake, this isn’t balance. This is
war.
Niche acquisition
Evolution by its non-directional temper will find ways to
select for new niche acquisition, and reward the new king of the new, unutilised
hill. Think of a small but ground-breaking tweak to the infinite
monkey-typewriter theorem; only monkeys that make any progress in writing
Shakespeare get paid in food. Now you have selection for monkeys that make
progress in writing Shakespeare. Let’s hope their success is influenced by genetic
element/s!
If an energy source is currently being unused, then evolution
will favour organisms that can utilise that niche more effectively than those
which can’t. It is such an elegant motor by which the universe nondirectionally
propels itself and matter into complexity, capable of self-replication. That is
what we are really talking about on a fundamental level – replication and the
ability to pass on information. If something can replicate, it has another
crack at existence, and therefore a greater chance at continued existence, when
compared to something that can’t replicate. Life eventually blooms as these
self-replicating molecules proliferate and accumulate over time, like a
billion-year PCR. That’s a pretty simple and elegant process which births the
biosphere and all it’s highly complex and competitive inter- and intra-relationships,
as some of these self-replicating molecules can replicate better than others,
depending on a myriad of complex situational factors. Basically, if it works,
it survives, generally speaking. There are obvious exceptions such as when
genes proliferate despite an organism’s best interest. But hey, if it still
works, and the organism still has enough fitness to replicate itself, then it
doesn’t really matter. Even domesticated animals fall into this; they had genes
which were selected for (by humans), and have continued to proliferate, despite
humans being responsible for the extinction of ninety-nine percent of all living
species on the planet. Yet gourmet herbivores outnumber us over a hundred-fold.
Sure, it’s not the traditional evolutionary path, but it’s still evolution
nonetheless. We’re not exempt.
The battle within organisms
Looking inward, we also find the war occurs within organisms;
within yourself. An example of this is development of cancers, which are a
result of a build-up of just the right mutations that mess with cellular
replication. Cancer is interesting, because you get cancers all the time, but your
body will correctly dispose of it. It’s when your body doesn’t get to it, it
can proliferate and get out of hand, developing the pathology we know as
cancer. Evolution within an organism is tricky, because in the case of cancer,
cancers that can feed via nutrient silk roads (blood vessels) while avoiding
immune system detection, can grow happily while weaker cancers are destroyed.
This is selection pressure within the organism which results in spread of
stronger, well-equipped cancers. The same thing applies to drug-resistant tumours;
only the strong survive, which will most likely go on consume the host. Cancer
also means, generally speaking that we beat life. The only thing left to kill
us, is our own shitty, mutation rate. Ageing in fact, is most likely caused by accumulation
of mutations. Someone fuse SSo7d to my polymerases please!
The case for DNA analysis
The battle is also occurring not just within the organism, but
on a gene level – and it’s more elegant than you’d think. Originally, evolution
was deciphered using comparative morphology with an alley-oop from the fossil
record. Comparative morphology is a crude tool which can often result in
incorrect classification and confuddlings, such as the turtle’s incorrect
classification as an anapsid due the lack of temporal fenestrae, or holes in
the skull near the temple region. They were correctly placed in the tree of
life as Diapsida by researchers, who looked at turtle DNA and worked out that
it was closely related to other diapsids (lizards and snakes), which have two
temporal fenestrae. This means it evolved much later than anapsids, which were
early-build reptiles. This is supported by the fossil record. It turns out that
part of the Testudine strategy was to armour up. Heavy bone growths covering
the two holes in their heads, along with development of a hard shell were selected
for, allowing them to outlast even the dinosaurs. Organisms that aren’t related
by a fairly recent common ancestor but share similar environments can develop
similar morphological traits. This is known as convergent evolution. This is a
key chink in the armour of morphological analysis, as the information required
to sort and organise higher organisms simply isn’t encoded.
However, that’s not to say morphology isn’t important; to be
able to divine the concept of evolution using the rough guide of morphology was
an amazing feat. What’s more amazing was the role synchronicity played, as it
was articulated by two men who’d never spoken or met, at around the same time,
Alfred Russel Wallace and Charles Darwin. The granularity of analysing DNA in
the perspective of evolution is mind blowing. There are issues with DNA
analysis, such as SNP reversions, horizontal gene transfer, convergent
evolution etc, so it makes sense that we are looking at all the evidence and
seeing what’s most likely true. We won’t ever really know for sure, unless we
were to rebuild a new Earth with all its original elements and compounds and
local star system environment and watch it in fast-forward, but even then…we’d
still need thousands of simulations to get a clear understanding of what most
likely happened. All that work to prove that turtles are diapsids, not
anapsids? Sure, why not. The future will be an interesting place, provided intelligence
isn’t selected against by The Great Filter.
The battle on a gene level
Genes don’t want to replicate themselves as they don’t really
want anything. However if they are capable of replicating, then they will.
Therefore, due to the nature of selection, if they provide advantages to an
organism, they will continue to hold their place within the replicating
organism. Early, self-replicating molecules gave up their individual autonomy
when they started working together with other self-replicating, to make
organisms. What we see when we look at an organism are the victors of a
GENErational war. The present genes (most likely but not always) provided an
advantage to an organism and allowed themselves to be replicated historically
all the way down through to the organism you are now looking at. They are
genetic remnants; palaeological artefacts passed down since the dawn of the
first self-replicating molecule over the last ~four billion years on this
planet. Therefore, these genes won their war, for now. But it’s a constant battle.
If they stop providing benefits, then they may be lost over time.
Alternatively, they can blackmail an organism into keeping them, by taking over
a role of another gene or attaching themselves to or near essential genes.
There are many strategies genes rely on which result in their continued
proliferation within the biosphere, and we probably don’t even understand one percent
of their unconscious tactics. Genes aren’t consciously doing these things, but
if they continue to persist within the organism without reducing its fitness too
detrimentally, we will continue to see those genes accumulate within a
population. Protein moonlighting is such strong
evidence for evolution and its ability to efficiently problem solve. Having one
gene perform multiple functions removes ancestral necessities such as gene
duplication events or multiple genes. It’s more efficient, and the gene itself
now has an insurance policy in case its original function becomes outdated.
Initially, the singular-function gene would have evolved, but over time, instead of evolving new
genes, current genes are re-purposed while still retaining their original
functional protein domains, therefore encoding more complex information into
the same amount of genetic material. Even crazier is that smaller genes can be
encoded within the same DNA sequence, running in either direction. The
efficiency is incredible, and unconsciously genius. It will take lifetimes to
tease the complexities apart.
Life as a consequence of entropy?
No matter what, all life is going to come to an end, it is
something we only truly experience in one direction, with the arrow of time.
Entropy demands it, and it is the price all life pays for existence. It is the
currency by which we measure life. Time is in all likelihood a consequence of
entropy. Life, in all probability is a consequence of time. As matter spreads and
energy runs out, we go from order to chaos. Atomic concentrations diffuse
outwards and decay. Energy flutters, and flourishes and dances around and
recollects parts of itself, increasing it’s already impressive efficient recycling
process. This isn’t an intelligent process. It’s just evolution, selecting for
and rewarding novel ways to obtain and utilise energy. It’s not balance, it’s
just entropy non-directionally finding more creative ways to recycle energy
over time through evolution. To fill as many niches and gaps as possible. If
there is an unutilised resource out there and enough time, evolution will
eventually select for organisms that can turn a once inhospitable environment,
unobtainable resource or indigestible compound into usable substrate.
How can you not be fascinated by the elegant, ever-changing,
violent nature of evolution? It’s fucking beautiful.
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