Posts Tagged ‘origin of life’

Two Clues to the Origin of Life

November 17, 2017

Two big CLUES to how life began on Earth.

1. There had to be continual energy.

Because of the energetic continuity requirement – which follows from the Darwinian evolutionary continuity principle (see Lahav (1999); Wolf and Koonin
(2007) and references therein) – the energy flows that deserve attention in evolu-
tionary context are those that remain constant on the evolutionary relevant, geolog-
ical timescale. This consideration essentially discounts the evolutionary importance of occasional energy inputs from impact bombardment, atmospheric electric
discharges, shock waves, volcanic explosions, and so on. It is also unlikely that life could notably depend on the chemical compounds that were produced or delivered during such occasional events. It seems implausible that the first life
forms could wait from one occasional event (e.g., volcanic explosion) to another to get energy and nourishment. There are no known organisms that obligatorily depend on such irregular sources of energy and matter.

2. Bases and UV.

The exclusive feature of natural
nucleobases is their unique photostability (Cadet and Vigny 1990). Since this trait is not related to the storage of genetic information, several authors (Skulachev 1969; Sagan 1973; Cadet and Vigny 1990) have noted that this property could have
been of some use when the UV flux at the surface of primordial Earth – owing to the absence of the ozone layer – was much stronger than it is now. Nucleobases apparently can absorb excess energy quanta from sugar-phosphate moieties and protect them from photo-dissociation (Goossen and Kloosterboer 1978). This feature explains why the UV damage to the backbones even of modern RNA and DNA molecules is 103–104 times less frequent than the destruction of nucleobases proper (Cadet and Vigny 1990). Under the assumption that the unique photostability of nucleobases could hardly be incidental, we have argued that
natural nucleotides should have been selected within the reach of solar light and that nucleobases may have protected the first RNA-like polymers from photo- dissociation (Mulkidjanian et al. 2003).

Both quotes from Mulkidhanian papers.

My suggestion is that life is the most stable chemical system under daily UV radiation. The problem with most origin of life scenarios is that there is nothing forcing the change except fate or fluke events. That problem is solved when the origin of live is a response to a daily cycle of UV. Then chemical systems have to change and adopt or they are destroyed.

Which is more probable, a one time pop up of 5 or so linked chemical steps that each have to occur in the proper order in a hostile environment that they are not protected in and that would quickly destroy each step, OR a chemical selection over millions of years of UV radiation?

My paper:
http://www.daviddarling.info/encyclopedia/U/UV_origin_of_life.html

For everything else see the website
tomhendricks.us

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Volcanic Moon and Bombardment Phase

October 20, 2017

Saw this about the Moon having a thin atmosphere 3.5 to 4 bya.

https://www.sciencedaily.com/releases/2017/10/171009091908.htm

I always wondered why the half of the moon facing earth was so cratered while the other side was not.

Could it be that this volcanic outgassing was pulled out of the Moon by the gravity of the Earth?

Then, if that is true, does that suggest that the bombardment, was not asteroids as much as it was the Earth forcing volcanic activity from the near side of the Moon?

Then, if there was not the severe bombardment phase, we can move back the OOL (origin of life) to an earlier time?

The Origin of Life – Difficult or Easy?

September 2, 2017

IF the origin of life was difficult then we are most likely not here.

If the origin of life was not difficult then we are most likely here.

The fact that we ARE here suggests that the origin of life was most likely not difficult.

The Lab

See tomhendricks.us

Life Origin Hypotheses

March 24, 2017

Life popped out of nothing in a one in a billion fluke event. Then with the least amount of defenses in its genetic structure it survived one of the most harsh environments in Earth’s history. That makes sense?
No the opposite does. Life is the chemical system that was the most adapted to that environment. It was chemically selected as the most stable response to the environment and that kept it from being destroyed, allowed it to continue and then to prosper.

Report – O2 on earth earlier than thought

October 7, 2015

Life is not a fluke one-time assembly, of chemicals that popped up out of nothing in one place. It’s a reaction to the environment over millions of years.

My ideas on the origin of life, are based on the idea that life was a reaction to UV and sunlight, in a daily cycle. That gets some support by this article showing how far back photosynthesis goes – much further than many had thought.

http://www.sciencedaily.com/releases/2015/10/151006192107.htm

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My paper:
UV PAPER http://www.daviddarling.info/encyclopedia/U/UV_origin_of_life.html
Catabolic and Anabolic evolved, but they did not blend.

Photo 3


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