THE LIFE ARC
OUTLINE of evolution
Life arose in the ocean. It remains wet.
Water, carbon, oxygen, boundary skin, one cell formed in a bubble but then contained a smaller bubble with a code-plan and that changed everything.
NUCLEUS: Mapping, variation
in/out, backward/forwards, the cell basics
THROUGHLINE: notochord, spine, bilateral
quadrapod, organizing principles
PASSTHROUGH: gi tract, the world made internal molecularly
secondary passthrough of gases to provide oxygen-in toxins-out
BRAIN: Fish/amphibian/dino/bird/reptile/
MAMMAL: primates, hominin
MUTATION/EVOLUTION
If it were not for the pressure of environment and occasional internal gene glitches, variations would not exist. The mechanism of evolution is that when variety develops, some versions will be slightly better in that environment and will persist, gradually becoming a prevalent new creature. This is not necessarily a matter of force or superior strength. A better use of water in the body or a different habit of rhythm in the day might be better adapted for survival.
These days there are MANY books that describe the long evolution of life on this planet. Your grandpa was not a monkey, but a one-celled microbe in the sea. However, there were interesting developments along the way, some of which have become semi-psychological but also actual physiological functions and concepts. Here are a few:
1. To be alive is to change. Failure to change is the same as dying. A corpse changes because it is not a composite of cooperating cells anymore, but disintegrating cells at the mercy of other entities (microbes, carrion eating animals and insects). Dryness can cause death or result from death because the process of circulation inside the body must not stop. Only the most primitive creatures can go completely dry and then come back to life, usually insects or plants, a few fish.
2. The first step towards “being” is the creation of a boundary between the guts of the cell and the sea at large. (This is also a psychological concept, all about psychic boundaries.) A living cell with a nucleus and other inclusions is very complex. Its primal ability is movement toward food and away from danger. This is always true of creatures unless the environment brings food and washes away debris, like a barnacle in the tide. The boundary itself must invent ways to take in food and throw out excesses, so there are ports in the cell-skin. It is not impermeable, but controls what goes in and out.
One layer of the brain cortex, which has several layers pushed against the skull and wrapped around the other parts, is concerned with mapping the body, on which it notes the plurality of neuron intakes by size on the map so that faces and hands are outsized big. Another set of neurons (I’m not sure where) remembers directions, speed and kinds of movement, position of the body, which is head and which is bottom and which goes “up”, whether one is next to a drop-off or a wall. This collection of operational information is acquired through experience but some of it seems to have become genetic. Earlier we did not know that learned experience could become preserved in a genome. Of course, we didn’t know we could insert genes or delete genes, entirely changing the results in the entity, the phenotye.
The development of the gastro-intestinal tract which leads from the mouth-inport to the anal-export presents the fact that the world is constantly passing through us. En route it encounters digestive squeezing and dissection into molecules that can travel in the blood to the cells. This world-within is also teeming with microbes and worms, sharing our food sources and producing their own molecules with DNA.
The great hard-to-swallow truth is that in-skin reality is quite different from what is out-skin. Neurons can only accept and carry code from the out-skin world. Much information in-skin takes the form of molecular code in solutions like hormones created by organs to regulate what those organs do. These exist in the blood and lymph. Blood differs by also including red blood cells that specialize in oxygen and immune cells that fight intruder.
Neuron systems are in two major systems, autonomic or smooth and striated, the latter likely to be voluntary. Autonomic nervous systems were once apparently divided into two parts, sympathetic and parasympathetic but more recently the third autonomic branch, which goes directly from brain to parts of the body that are expressive. I’m much influenced by polyvagal theory but will discuss it later.
THE DARK SIDE
The dark side of this upbeat theory of adapting (improving) mutation/selection is very dark indeed. The new versions of a creature would not be able to replace the old versions, less well-adapted, unless the old ones die. Selection means survival. Quite aside from environmental change, like the gradual change of temperature we’re experiencing worldwide or the sudden impact of an asteroid like the one that evidently ended the dinosaurs, each individual creature has a life-arc of new-mature-aging-senile-death. Something in living creatures is a clock that will expire.
In addition, generations have a rhythm of childhood-maturing-birthing-raising that creates a new kind of person, each raised in a different environment and therefore “mutated.” Society becomes “shingled” with overlapping generations and some of them will qualify as more “fitting” than their progenitors. The levels of attachment, achievement and separation will determine much of what happens over the centuries as we creatures react to their surroundings. Today’s teenagers will vote in the next election after this one.
In some times and places humans lived barely long enough to create and raise children. If they didn’t manage that, their genealogical sequence would stop. In the end there were not enough surviving dinosaurs, except some adapted to be birds. But creatures like sharks were so enduring that their kind is aeons old though we haven’t found any that are eternal. We are living in the midst of ending species due to environmental changes that were often made by us. A great extinction comes just as we are discovering many exotic living things, just as we are attaching to species not our own, elephants and koala bears. We realize that we might end our own sequence of hominins before a new one could emerge from genetic or generational sources. We may be the end of this line, though life would go on.
CONTINUITY
Genomes are persistent and continue through the additions, subtractions and adaptations of time. They are invasive so that babies send their cells into their mothers, dog-owners exchange genes with their pets, and elements are still present even after millennia of evolution. When humans are intimate when taking care or having sex, they begin to share microbes. We can talk about our “inner fish” in terms of how structures and functions like gill arches can become the nasopharyngeal apparatus of hearing and speech in humans.
Genomes are cumulative so that early bits of protein mapping will simply be overlain by new instructions. This is apparent during gestation when it once was thought that every fetus went through the stages of evolution. Once in a while something installed more recently can buckle, allowing the old function to come back, particularly when the function is psychological like items in the autonomic nervous system that are connected to the brain. The reaction to primal threats is particularly impactful.
LIFE WANTING TO LIVE
The major drive of creatures is to survive. In order to do this it is necessary to maintain homeostasis, which is a matter of keeping the business of being alive within limits -- not too much and not too little, whether that’s about salt or sugar, blood pressure, shelter, or any of a myriad of other necessities for life. These functions are most often described in single terms as a kind of thermostat. In larger more abstract terms it is portrayed as a stream with two banks, one for too much and one for too little. But most of it is unconscious and must be accessed through instruments or chemical analysis. Thermometers, glucose monitors and measures of blood pressure.
The deepest continuous part of the stream is geologically called the “thalwag” which might not be obvious from the surface of the water, but it makes a nice metaphor for most basic impelling force of the desire to survive and the creature’s ability to feel it. There are psychological words for that. When the person is following his thalwag, in harmony and “in the zone,” he is contented. For a human, conscious awareness of it may be a precursor for whatever it is that triggers the feeling of Holiness, which is not just feeling one’s insides but also feeling the world beyond the skin. Some feel that origin of religious systems and institutions is in a search for meaning in life and consolation for the knowledge of death.
When I’ve posted a complete rough of this thesis, I’ll add a bibliograpy.
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