Life starts with viruses

I remember, in school, being told a definition of what life that had clearly been designed to exclude viruses – it incidentally excludes some sub-types of bacteria, and can be critiqued in various ways because it takes for granted that the environment in which the parent was able to survive is available to the child, in which to grow up – and finding myself uncomfortable about the being like us is better than the alternatives prejudice this contained. I have since paid some attention to differnt theories of the origin of life, which have reinforced that initial naïve discomfort.

Clay crystal blooms

In particular, somewhere in the intervening decades, I read an account of a possible class of pathways for life to arise that – instead of the story all happening in the oceans – noted that certain clays, when found in puddles, as the puddle dries out, form (inorganic) crystal flowers whose physical form and chemical structure cause them function as catalysts for various chemical reactions, some of them organic. In particular, such blooms can catalyse the creation of some of the building blocks of life, from chemistry we have reasonable grounds to suppose existed in the air and water of Earth not long after its mess settled down from the process of formation.

The other thing clay crystals can do, when they dry out and are broken by wind and sand into dust, is produce fragments of dust that – when they land in a saturated broth of chemistry containing the ions of which the crystal was formed, – can serve as seeds from which the broth shall grow new crystal blooms of the same kind. This might not be life (at least by the definition I was taught in school) but it is something whose existence tends to catalyse the creation of more of the same stuff, later. That has some important things in common with life – indeed, one could even use it as an alternate (albeit certainly broader) definition of what constitutes life. If we were to broaden the definition in this way, we would have to admit that this is far from life as we know it; yet it has one important property that is central to what we think of as life.

This means it's possible that, whererver the muck of Earth collected in pools whre land was roughly level and below higher land from which rain ran off on its way towards sea, such clay crystal blooms could have served to increase reaction rates (that's what a catalyst does) between chemicals – known to be present in Earth's early air and water – that lead to chemicals that are pre-requisites of the chemistry of life. Indeed, the same process could conceivably have applied during the formation of the solar system, as clumps of muck in the swirl around a central nexus (which became The Sun, eventually) were warmed and cooled by their movement between warmer and coooler regions of muck orbiting that centre (near which more stuff collided, causing more warmth; further away, there were fewer collisions, so it was cooler), to cause such clay crystal flowers to seed the muck of which Earth was formed with interesting chemistry.

No matter how soon that process began, it clearly provides a channel for inorganic chemistry to catalyse organic chemstry, in ways that can lead to complex organic (i.e. carbon-dominated) molecules to arise. Furthermore, the places where this could arise (puddles in sporadically-flooded level land, or lumps of muck in the nascent solar system) would be prone to repeated cycles of wet/warm and dry/cold; in they drying from a wet phase, the crystals blooms get to be where much of the water-miscible chemistry is concentrated, allowing its chemistry to be catalysed efficiently; in th edry phases, complex organic products of that catalysis – and results of reactions among such products, when somewhat concentrated by the drying puddle – are apt to be physically attached to fragments of clay crystal flowers. Though the earlier puddle may be disrupted, that attachment is apt to lead to the non-trivial organic chemistry hanging around with organic clay fragments that are, in their turn, capable of serving as seeds for the formation of later clay-crystal blooms of the kinds that catalyse the precursors of the organic chemistry that's physically stuck to the fragment of clay crystal that strated the new bloom.

Now, if that organic chemistry is capable of catalysing – from the simpler organic chemistry whose formation the clay crystals catalyse – more of itself, that'll stick to the fresh crystal bloom, then we have a self-replicating pattern in the behaviour of matter. (We might be inclined to think of this as, at least, a precursor of life.) Flakes of the new crystal flower, carrying organic dirt with self-catalyzing capabilities, shall blow on the wind and land in later puddles. Such flakes of gunky clay-crystal flower shall thus propagate, in so far as there are suitable puddles. In so far as the crystal flower is one apt to arise as long as the right chemistry is present (regardless of whether a suitable flake of crystal lands just as the puddle dries out to saturation; if the flake arrives before that it just disolves, losing its prior crystal structure and hence its ability to be a seed), the organic gunk can still do its job once the puddle does dry out, as long as the right (common) crystal flowers do arise (and create the right precursors).

Puddles as precursors of cells

Whether the initial puddles of organic interesting goo arise from clay crystal flowers or some other process, I suppose early precursors of life begin with some recurrent pattern of chemical activity in which a natural process, that can produce the preccursors of interesting biochemistry, is apt to be polluted with some organic chemistry that is apt to catalyze imperfect copies of itself out of the natural products of the recurrent process in question.

As long as that is happening, consider what happens to the organic component of those recurrent puddles.

Goo invents proteins, including enzymes

Viruses invent RNA

Viruses record libraries of recipies in pudddles, as DNA

Viruses teach their puddles how to not work for other viruses

Renegated puddles defend themselves against even the viruses that made them

Life (as we know it)

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