Tuesday, September 01, 2020


If the basic “religious” question of people is how to defeat death, then ideas like another world where existence goes after death or reincarnation that brings everyone back to life make sense.  Modern science makes both of those ideas impossible to make actual, though there are attempts to freeze people and restore life later or to figure out which genes cause aging so as to knock them out.

The most blunt humanist knows that at death the body goes back to being the basic molecules and elements of the flesh and bone, to be recycled by insects, gases, fertility, and so on.  Never to be human again as that unique human being who died.

But most students of organic chemistry will admit that carbon-based traces can arrive on asteroids and that the earth has spontaneously created the ordering bits of inert rock and muck that support life, defined by the use of DNA (double strand helix) or RNA (single strand helix), which are four basic molecular configurations (differing from each other by one out of four of the basic molecules) arranged in long spirals and contained in cells which are separated from everything else by a cell wall.  There are also bits of this code that float outside cells but try to get in — we are currently very aware of these viruses.  Barely in our awareness are little circles of DNA in human cells that have puzzling purposes.  There is still a lot of mystery.

But there is also a lot of continuousness:  dogs and their masters, infants and their mothers, caregivers and their charges, all share bits of DNA in breath and blood.  Traces of unique DNA have become crime-solving clues because they were left behind, particularly in body fluids.  It is this ease of transfer that makes viruses contagious, but also makes it possible to send particular genes into cells that damage code.

We tend to think of survival in terms of force and control, survival of the big and powerful, instead of fittingness, which allowed the little mammals to live after the dinos were extinct because the little creatures fit the conditions better.  The traditional depiction of evolution through mutation is as a tree, branching as it goes “higher” — which therefore carries the notion that “higher” is “better.”  More like us.  But it is more helpful to picture evolution as the branching rivulets of a river delta before reaching the sea.  Crossing, merging, separating, following the contours of the larger environment but always in process — these are more characteristic of evolution.  A stream can dry up, go extinct.

The little rivulets of time and change through mutations of DNA are interrupted by living creatures, both tiny and primitive, and pooled elaborate creatures with bodies defined by each one having a skin that contains all the cells sharing the same DNA.  As time goes on, outsider DNA can also creep in, but every creature has a skin that contains it.  Humans can be thought of as co-operatives of cells using the same DNA but elaborate enough to specify which DNA operates which cells: some dictating bone, some creating a liver, some making guts, and so on.  The genome is joined by the epigenome, which can change genes by “methylating” and which can carry over generations after a major event.  Also, the micronome, little bacterial or viral beings with separate DNA, join the body and participate in its operation, sometimes for better and sometimes for ill.  

The proteome, the kinds of proteins that interact, also has its own identity and influence.  It is possible for a molecule to mis-fold for some reason, creating disease.  Strangely these molecules can make others be like them.  I used to have a running argument with a geologist that a person in a part of the country with one isotope (version) of an element would be subtly different than one different because from a different place.  The whole system is tight but loose — wobbly but functional.  Good enough or gone.

This is a blog — a weblog — and therefore I include a lot of quotes and links.  Like this one:

How Life Could Continue to Evolve, On the origin of an interstellar species.”  by Caleb Scharf,a British-born astronomer and the director of the multidisciplinary Columbia Astrobiology Center at Columbia University, New York.”  http://www.calebscharf.com

In our times research and possibilities dance together and the music is from science, fiction, poetry, and the facts — so far — which accrue to a kind of religious platform, not based on a proclaimed certainty, but rather a search for the other side of the horizon of what we know already.

At the same time the human access to transportation anywhere on the planet, plus the loosening of moral codes and unlimiting of access to variations, means that an individual may carry much “horizontal” genetic change that was never possible before.  The pressures of the environment are also new, for instance the universal existence of plastic or manmade chemicals.  We can expect humans to vary much more and more quickly than before.

Scharf, being a trained astrophysicist, is interested in the known exchange of materials between planets, perhaps carried by asteroids, and the acquisition of new materials through asteroids and comets.  New materials mean new forms.  Scharf is generous enough to allow machines (which in his mind is more like technology) to join the party, citing the ability to create a new person based on material from three individuals: father, mothergenome and ovumhome.  Not enough time has passed to know how such a composite will turn out eventually, but so far, so good.

But this wide-sight scientist does not tackle the near-genetic forces of culture that award some babies extra care but possibly also limits them.  This is where fiction, particularly sci-fi picks up the threads.  Also, a moral component comes out of fiction: who can exchange genes with whom, and what will come of it, and why we should allow that particular strategy. 

So you’ll remember this, I’ll tell the old joke about the WWII Nazi intention to mess with the genome by urging their soldiers to rape women.  In one such instance, the Aryan in question stood up, saluted and said, “In nine months, you will have a fine blonde baby!”

The French resistance woman, resting on her back and elbows, answered, “Much sooner than that you will have a fine case of venereal disease.” 

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