The Origins Of Life On Earth

[INT21]

As such, the cell is the most commonly cited elemental or canonical example of a living system.

Reproduction is not an essential element for qualifying as a living system. Reproduction is an essential element of the network(s) of processes definitive of a species rather than an individual organism.

However, that doesn't explain how a cell nucleus can divide and branch of into different cells, not straight copies of itself.
What programs the DNA ?

 

[Mythopoeika]

However, that doesn't explain how a cell nucleus can divide and branch of into different cells, not straight copies of itself.
What programs the DNA ?

A combination of fractal branching and probability.
See snowflakes? They're all different. Crystalline ordering from chaos.

 

[INT21]

Never liked the snowflake idea. Simply because it is not possible to confirm it.

At best one can say that every snowflake we have examined so far appears to be different. Is there a World Wide Snowflake data base ? How do they check ?

It's rather like the claim that there MUST be other civilisations out there. We just don't know.

 

[EnolaGaia]

Agreed - But from where or why would any other of the inorganic processes occurring throughout the universe suddenly, or even over time, begin to
"self-organized / self-sustaining networks of processes" .

Given the proper conditions, combination of ingredients, and arrangement there are a number of inorganic compounds that can spontaneously initiate and even sustain cyclical processes or transformations. See: auto-catalytic (reactions; processes)

- What kick-starts such a self organization and self-sustaining process? .

There is no intrinsic requirement for an external inducement if the conditions and participating components (see above) are present and interact.

{Crystals might organize and sustain but there is no living life process in a crystal}.

Crystallization is a good example of a process which plays out deterministically with respect to a substance's molecular form, lattice structure, and envirionmental conditions. In this sense, and in this sense alone, crystals "self-organize" in terms of their aggregate or gross geometrical form. They do not, however, recursively self-organize themselves in terms of their internal constitution, and they do not sustain themselves by proactively maintaining and / or replacing their own components.

- Can the 'spark of life' be a possibility in the random chemical/physical events
of nature? - You could say yes, but still 'self organization' sounds like an external process or intelligence not inherent to inorganic reactions..

Uh, no ... The "self" in "self-organization" means that an entity's course of action / interaction / transformation is governed by the structure, arrangement(s), and transformational possibilities afforded by these first two things - all in or from the self-organizing entity itself.

 

[EnolaGaia]

However, that doesn't explain how a cell nucleus can divide and branch of into different cells, not straight copies of itself.
What programs the DNA ?

The issue at hand is what constitutes "biological life". As I already stated, reproduction is not a necessary requirement for the operation of a single "living" organism.

 

[Comfortably Numb]

Geologists Determine Early Earth Was a 'Water World'

Source: ancient-origins.net
Date: 4 March, 2020

The Earth of 3.2 billion years ago was a "water world" of submerged continents, geologists say after analyzing oxygen isotope data from ancient ocean crust that's now exposed on land in Australia.

And that could have major implications on the origin of life.

"An early Earth without emergent continents may have resembled a 'water world,' providing an important environmental constraint on the origin and evolution of life on Earth as well as its possible existence elsewhere."

So wrote geologists Benjamin Johnson and Boswell Wing in a paper just published online by the journal Nature Geoscience.

https://www.ancient-origins.net/news-general/water-world-0013372

 

[AlienView]

The issue at hand is what constitutes "biological life". As I already stated, reproduction is not a necessary requirement for the operation of a single "living" organism.

But wasn't reproduction necessary for it to exist?

Yes, I've read about so called created lifeforms in the lab - But are they alive?

Or this answer found on Quora:

Has life been created in the laboratory?
"No, we can not and it will never happen.

No matter what kind of XNA, RNA or DNA we create in a lab, and no matter what kind of synthetic surroundings we give it, the materials will not reproduce UNLESS we insert the materials in vivo (in an already living organism). All synthetic materials sit there lifelessly. People have tried zapping them with electricity and causing all sorts of chemical reactions to animate the synthetic matter, but the movements caused are random and destructive, not functional and efficient like matter movements in living organisms.

Reproduction of any kind requires some very precise movement. Molecules don't just reproduce because they are near a molecule they want to resemble. In the synthetic lab, nothing moves with the efficient, precise, coordinated, perfectly timed and placed functional animation of life.

People need to understand that life is intelligent and conscious, not automatonic or mechanistic. "
- Tyke Morris
https://www.quora.com/Has-life-been-created-in-the-laboratory

 

[EnolaGaia]

But wasn't reproduction necessary for it to exist?

Already asked and answered - No.

Yes, I've read about so called created lifeforms in the lab - But are they alive?

Not unless they can autonomously maintain their own structure as a result of their own actions (processes) and interactions with the environment.

Or this answer found on Quora ...

That's not an answer - it's a declaration that reproduction must require an already living organism. It says nothing about what qualifies an entity as a living organism in the first place.

 

[Xanatic*]

Years ago some scientists created a polio virus from dead matter stitched together. It seemed to work.

https://www.sciencemag.org/news/2002/07/poliovirus-baked-scratch

 

[Comfortably Numb]

Process that might have led to first organic molecules

New research could have relevance to search for extraterrestrial life, green chemistry

Source: sciencedaily.com
Date: 8 September, 2020

New research led by the American Museum of Natural History and funded by NASA identifies a process that might have been key in producing the first organic molecules on Earth about 4 billion years ago, before the origin of life. The process, which is similar to what might have occurred in some ancient underwater hydrothermal vents, may also have relevance to the search for life elsewhere in the universe. Details of the study are published this week in the journal Proceedings of the National Academy of Sciences.

All life on Earth is built of organic molecules -- compounds made of carbon atoms bound to atoms of other elements such as hydrogen, nitrogen and oxygen. In modern life, most of these organic molecules originate from the reduction of carbon dioxide (CO2) through several "carbon-fixation" pathways (such as photosynthesis in plants). But most of these pathways either require energy from the cell in order to work, or were thought to have evolved relatively late. So how did the first organic molecules arise, before the origin of life?

To tackle this question, Museum Gerstner Scholar Victor Sojo and Reuben Hudson from the College of the Atlantic in Maine devised a novel setup based on microfluidic reactors, tiny self-contained laboratories that allow scientists to study the behavior of fluids -- and in this case, gases as well -- on the microscale. Previous versions of the reactor attempted to mix bubbles of hydrogen gas and CO2 in liquid but no reduction occurred, possibly because the highly volatile hydrogen gas escaped before it had a chance to react. The solution came in discussions between Sojo and Hudson, who shared a lab bench at the RIKEN Center for Sustainable Resource Science in Saitama, Japan. The final reactor was built in Hudson's laboratory in Maine.

[...]

https://www.sciencedaily.com/releases/2020/09/200908170535.htm

 

[EnolaGaia]

This is news to me - the impact origin of life hypothesis. Extrapolating backward from evidence of subterranean hydrothermal regions as havens for microbes after the Chicxulub impact event has led some researchers to suggest such impact-induced environments were the original birthplace(s) for terrestrial life.

Biologists Discover Ancient Microbial Ecosystems Beneath The Dinosaur-Killer Crater

How did life arise on Earth? How did it survive the Hadean eon, a time when repeated massive impacts excavated craters thousands of kilometres in diameter into the Earth's surface? Those impacts turned the Earth into a hellish place, where the oceans turned to steam, and the atmosphere was filled with rock vapour. How could any living thing have survived?

Ironically, those same devastating impacts may have created a vast subterranean haven for Earth's early life. Down amongst all those chambers and pathways, pumped full of mineral-rich water, primitive life found the shelter and the energy needed to keep life on Earth going. And the evidence comes from the most well-known extinction event on Earth: the Chicxulub impact event.
A new study presents evidence that the Chicxulub crater was host to an enormous subterranean network of hydrothermal vents that could have provided a sanctuary for microbial life.

By extension, much earlier impact craters likely provided the same sanctuary. The study is titled 'Microbial Sulfur Isotope Fractionation in the Chicxulub Hydrothermal System'. The lead author is David Kring from the Lunar and Planetary Institute. It's published in the journal Astrobiology.

The idea that life could have arisen and persisted in the network under impact craters is called the impact origin of life hypothesis. David Kring is a leading scientific voice supporting that hypothesis.

While massive repeated impacts made Earth's surface uninhabitable during the Hadean eon, the same wasn't likely true of the region under the impact craters.

According to Kring, those same impact events "…were producing vast subsurface hydrothermal systems that were perfect crucibles for pre-biotic chemistry and habitats for the early evolution of life." ...

FULL STORY: https://www.sciencealert.com/biolog...ecosystems-beneath-the-dinosaur-killer-crater

 

[EnolaGaia]

Here are two overviews of the development of this impact hypothesis.

The Inner Solar System Impact Cataclysm Hypothesis & The Impact-Origin of Life Hypothesis
(Date unknown)
https://www.lpi.usra.edu/science/kring/Kring_Cataclysm_ConceptDevelopment.pdf

UPDATED STATUS OF THE IMPACT – ORIGIN OF LIFE HYPOTHESIS.
(2019)
https://www.hou.usra.edu/meetings/habitability2019/pdf/1037.pdf

The primary person for this hypothesis is David Kring. His webiste is at:
https://www.lpi.usra.edu/science/kring/

 

[Comfortably Numb]

Hoping this is the most appropriate thread:

This Simple 3-Minute Video Will Change Your Perception of Time Forever

Source: sciencealert.com
Date: 25 December, 2020

We all know that Earth is old, but it's hard to put into perspective just how old it is.

After all, what does 4.5 billion years really mean? How do you even comprehend that amount of time with our short-lived human brains?

Well, Business Insider has done a pretty incredible job of it in this 3-minute animation, by displaying the timeline of Earth if time was the distance from Los Angeles to New York. And, oh boy, our world-view will never be the same.

[...]

https://www.sciencealert.com/this-simple-3-minute-video-will-change-your-perception-of-time-forever

 

[gordonrutter]

Hoping this is the most appropriate thread:

This Simple 3-Minute Video Will Change Your Perception of Time Forever

Source: sciencealert.com
Date: 25 December, 2020

We all know that Earth is old, but it's hard to put into perspective just how old it is.

After all, what does 4.5 billion years really mean? How do you even comprehend that amount of time with our short-lived human brains?

Well, Business Insider has done a pretty incredible job of it in this 3-minute animation, by displaying the timeline of Earth if time was the distance from Los Angeles to New York. And, oh boy, our world-view will never be the same.

[...]

https://www.sciencealert.com/this-simple-3-minute-video-will-change-your-perception-of-time-forever

If the entire history of the planet is the length of your arm, if you take a nail file and drag it once across the nail of your longest finger you have just erased the entire existence of humans.

 

[feinman]

If the entire history of the planet is the length of your arm, if you take a nail file and drag it once across the nail of your longest finger you have just erased the entire existence of humans.

It's that easy?! I'll be right back... Doing it for the other animals.... Done! Waitaminit, still here... Oh.. "If the entire history..."

 

[EnolaGaia]

Newly published research proposes a novel resolution to previous issues relating to DNA vs. RNA and how they arose to serve as the key components for life on earth.

Discovery Supports a Surprising New View of How Life on Earth Originated

Chemists at Scripps Research have made a discovery that supports a surprising new view of how life originated on our planet.

In a study published in the chemistry journal Angewandte Chemie, they demonstrated that a simple compound called diamidophosphate (DAP), which was plausibly present on Earth before life arose, could have chemically knitted together tiny DNA building blocks called deoxynucleosides into strands of primordial DNA.

The finding is the latest in a series of discoveries, over the past several years, pointing to the possibility that DNA and its close chemical cousin RNA arose together as products of similar chemical reactions, and that the first self-replicating molecules — the first life forms on Earth — were mixes of the two.

The discovery may also lead to new practical applications in chemistry and biology, but its main significance is that it addresses the age-old question of how life on Earth first arose. In particular, it paves the way for more extensive studies of how self-replicating DNA-RNA mixes could have evolved and spread on the primordial Earth and ultimately seeded the more mature biology of modern organisms.

“This finding is an important step toward the development of a detailed chemical model of how the first life forms originated on Earth,” says study senior author Ramanarayanan Krishnamurthy, PhD, associate professor of chemistry at Scripps Research.

The finding also nudges the field of origin-of-life chemistry away from the hypothesis that has dominated it in recent decades: The “RNA World” hypothesis posits that the first replicators were RNA-based, and that DNA arose only later as a product of RNA life forms. ...

FULL STORY:
https://scitechdaily.com/discovery-supports-a-surprising-new-view-of-how-life-on-earth-originated/

INFO ABOUT THE PUBLISHED REPORT:
https://onlinelibrary.wiley.com/doi/10.1002/anie.202015910

 

[EnolaGaia]

As if locating and analyzing the evidence for earth's earliest life wasn't difficult enough ... Recent research demonstrates that what appear to be microbial fossils may instead represent the products of abiotic chemical processes - i.e., 'false positives' with respect to being biotic fossils.

Organic Biomorphs: Experiments Show the Record of Early Life Could Be Full of “False Positives”

For most of Earth’s history, life was limited to the microscopic realm, with bacteria occupying nearly every possible niche. Life is generally thought to have evolved in some of the most extreme environments, like hydrothermal vents deep in the ocean or hot springs that still simmer in Yellowstone. Much of what we know about the evolution of life comes from the rock record, which preserves rare fossils of bacteria from billions of years ago. But that record is steeped in controversy, with each new discovery (rightfully) critiqued, questioned, and analyzed from every angle. Even then, uncertainty in whether a purported fossil is a trace of life can persist, and the field is plagued by “false positives” of early life. To understand evolution on our planet—and to help find signs of life on others—scientists have to be able to tell the difference.

New experiments by geobiologists Julie Cosmidis, Christine Nims, and their colleagues, published on January 28, 2021, in Geology, could help settle arguments over which microfossils are signs of early life and which are not. They have shown that fossilized spheres and filaments—two common bacterial shapes—made of organic carbon (typically associated with life) can form abiotically (in the absence of living organisms) and might even be easier to preserve than bacteria. ...

“One big problem is that the fossils are a very simple morphology, and there are lots of non-biological processes that can reproduce them,” Cosmidis says. “If you find a full skeleton of a dinosaur, it’s a very complex structure that’s impossible for a chemical process to reproduce.” It’s much harder to have that certainty with fossilized microbes. ...

FULL STORY: https://scitechdaily.com/organic-bi...-early-life-could-be-full-of-false-positives/

 

[EnolaGaia]

Here are the bibliographic particulars and abstract from the published research paper. The full paper (in PDF format) can be accessed from the page linked below.

Organic biomorphs may be better preserved than microorganisms in early Earth sediments
Christine Nims; Julia Lafond; Julien Alleon; Alexis S. Templeton; Julie Cosmidis
Geology (2021)
https://doi.org/10.1130/G48152.1

The Precambrian rock record contains numerous examples of microscopic organic filaments and spheres, commonly interpreted as fossil microorganisms. Microfossils are among the oldest traces of life on Earth, making their correct identification crucial to our understanding of early evolution. Yet, spherical and filamentous microscopic objects composed of organic carbon and sulfur can form in the abiogenic reaction of sulfide with organic compounds. Termed organic biomorphs, these objects form under geochemical conditions relevant to the sulfidic environments of early Earth. Furthermore, they adopt a diversity of morphologies that closely mimic a number of microfossil examples from the Precambrian record. Here, we tested the potential for organic biomorphs to be preserved in cherts; i.e., siliceous rocks hosting abundant microbial fossils. We performed experimental silicification of the biomorphs along with the sulfur bacterium Thiothrix. We show that the original morphologies of the biomorphs are well preserved through encrustation by nano-colloidal silica, while the shapes of Thiothrix cells degrade. Sulfur diffuses from the interior of both biomorphs and Thiothrix during silicification, leaving behind empty organic envelopes. Although the organic composition of the biomorphs differs from that of Thiothrix cells, both types of objects present similar nitrogen/carbon ratios after silicification. During silicification, sulfur accumulates along the organic envelopes of the biomorphs, which may promote sulfurization and preservation through diagenesis. Organic biomorphs possessing morphological and chemical characteristics of microfossils may thus be an important component in Precambrian cherts, challenging our understanding of the early life record.

SOURCE: https://pubs.geoscienceworld.org/gs...rganic-biomorphs-may-be-better-preserved-than

 

[EnolaGaia]

Aren't we the lucky ones! :smug:

We've Found The Best Time And Place to Live in The Milky Way... And It's Not Here

More and more, it seems that the existence and persistence of life on Earth is the result of sheer luck. According to a new analysis of the history of the Milky Way, the best time and place for the emergence of life isn't here, or now, but over 6 billion years ago on the galaxy's outskirts.

That specific location in space and time would have afforded a habitable world the best protection against the gamma-ray bursts and supernovae that blasted space with deadly radiation.

As of about 4 billion years ago, the central regions of the galaxy (which include the Solar System) became safer than the outskirts - safe enough for life to emerge, if not quite as safe as the outskirts had been. ...

FULL STORY: https://www.sciencealert.com/when-w...-in-the-milky-way-not-where-we-are-apparently

 

[EnolaGaia]

... The Earth of 3.2 billion years ago was a "water world" of submerged continents, geologists say after analyzing oxygen isotope data from ancient ocean crust that's now exposed on land in Australia. ...

Subsequent and newly-published geological research further supports the idea that the earth was nearly or wholly water-covered during the Archaen Eon. Where did all that extra water go? The cooling mantle absorbed it.

Ancient Earth Really Was a Serene Water World, New Evidence Confirms

According to a new analysis of the features of Earth's mantle over its long history, our whole world was once engulfed by a vast ocean, with very few or no land masses at all. It was an extremely soggy space rock.

So where the heck did all the water go? According to a team of researchers led by planetary scientist Junjie Dong of Harvard University, minerals deep inside the mantle slowly drunk up ancient Earth's oceans to leave what we have today.

"We calculated the water storage capacity in Earth's solid mantle as a function of mantle temperature," the researchers wrote in their paper.

"We find that water storage capacity in a hot, early mantle may have been smaller than the amount of water Earth's mantle currently holds, so the additional water in the mantle today would have resided on the surface of the early Earth and formed bigger oceans.

"Our results suggest that the long‐held assumption that the surface oceans' volume remained nearly constant through geologic time may need to be reassessed." ...

FULL STORY:
https://www.sciencealert.com/we-just-got-even-more-evidence-that-ancient-earth-was-a-water-world

PUBLISHED RESEARCH REPORT:
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020AV000323

 

[Comfortably Numb]

Subsequent and newly-published geological research further supports the idea that the earth was nearly or wholly water-covered during the Archaen Eon.

Wow!! Thanks for this update.



Just something which came to mind!

"In the beginning God created the heavens and the earth. Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters...".

Genesis 1:1-3

 

[EnolaGaia]

Newly published research involving analysis of the currently prevalent estimate of early earth's atmosphere has determined that atmospheric chemistry would have made it more difficult for lightning to occur. If true, this means certain estimates for how long it took the "primordial soup" to begin generating prebiotic molecules will have to be re-thought.

Primordial Earth Had a Major Difference in Its Skies We Didn't Realize Until Now

Standing on Earth almost 4 billion years ago would have been an incredibly hot, desperately lonely, and very short experience – what with there being no oxygen. Now, new research suggests there would have been less lightning around than there is in modern times as well.

This could make a difference to any of the hypotheses that suggest lightning may have been involved in sparking the earliest life on our planet. If lightning strikes were actually less common on the early Earth than previously thought, that affects those calculations.

To dig deeper, researchers examined how streamer discharges – the sparks that start lightning – might have formed in an atmosphere dense in carbon dioxide and molecular nitrogen, as the atmosphere of the primordial Earth is now thought to have been. ...


To complicate matters, we're not exactly certain what the atmosphere of early Earth was like. Here, the scientists used the carbon dioxide and nitrogen hypothesis first put forward in the 1990s by geoscientist James Kasting.

An older proposal from Stanley Miller and Harold Urey, published in the 1950s, suggests that methane and ammonia were actually dominant in the atmosphere during the first billion years of Earth. ...

What all of this means is that the process of producing and building up the prebiotic molecules key to life, via lightning strikes, would have taken longer if recent ideas about the atmosphere of the early Earth are right.

The researchers don't specifically quantify how much longer; they only modeled one of the earliest stages in the process of lightning formation, and there remain a lot of unknowns. ...

FULL STORY: https://www.sciencealert.com/there-was-probably-less-lightning-on-the-early-earth-and-here-s-why

PUBLISHED RESEARCH REPORT:
Köhn, C., Chanrion, O., Enghoff, M. B., & Dujko, S. (2022).
Streamer discharges in the atmosphere of Primordial Earth.
Geophysical Research Letters, 49, e2021GL097504.
https://doi.org/10.1029/2021GL097504

FULL RESEARCH REPORT: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL097504

 

[Ronnie Jersey]

So supposedly the earth is billions of years old, dinosaurs lived through the Mesozoic Era, then went extinct 65 million years ago, and humans (or some type of human) sprang up around that time. apparently there are tracks of dinosaurs and 'humans' walking in the same areas.
Meanwhile the earth went through ice ages, etc. - so what could be next?

 

[Ascalon]

So supposedly the earth is billions of years old, dinosaurs lived through the Mesozoic Era, then went extinct 65 million years ago, and humans (or some type of human) sprang up around that time. apparently there are tracks of dinosaurs and 'humans' walking in the same areas.
Meanwhile the earth went through ice ages, etc. - so what could be next?

Are you serious? Hominids and dinosaurs coexisting? No credible source ever has made that assertion.
Jog on.

 

[Ronnie Jersey]

I've read about that many times, and if you notice I said 'apparently' -
Jog on yourself.

 

[Ronnie Jersey]

Well apparently meteorites helped start up life on earth?

Evidence suggests life on Earth started after meteorites splashed into warm little ponds​

Life on Earth began somewhere between 3.7 and 4.5 billion years ago, after meteorites splashed down and leached essential elements into warm little ponds, say scientists at McMaster University and the Max Planck Institute in Germany. Their calculations suggest that wet and dry cycles bonded basic molecular building blocks in the ponds' nutrient-rich broth into self-replicating RNA molecules that constituted the first genetic code for life on the planet.

https://phys.org/news/2017-10-evide...rsity and the Max Planck Institute in Germany.

 

[Tunn11]

Well apparently meteorites helped start up life on earth?

Evidence suggests life on Earth started after meteorites splashed into warm little ponds​

Life on Earth began somewhere between 3.7 and 4.5 billion years ago, after meteorites splashed down and leached essential elements into warm little ponds, say scientists at McMaster University and the Max Planck Institute in Germany. Their calculations suggest that wet and dry cycles bonded basic molecular building blocks in the ponds' nutrient-rich broth into self-replicating RNA molecules that constituted the first genetic code for life on the planet.

https://phys.org/news/2017-10-evidence-life-earth-meteorites-splashed.html#:~:text=Life on Earth began somewhere between 3.7 and,University and the Max Planck Institute in Germany.

Or could the wet/dry alternation be down to tides, meaning that the oversized moon was a factor in the origin of life?

 

[Ronnie Jersey]

Or could the wet/dry alternation be down to tides, meaning that the oversized moon was a factor in the origin of life?

I'm sure there were many things contributing to the start-up of life, probably much more than we know.
But it's interesting about the meteorite explanation, which would mean that many planets could be teeming with all sorts of life?

 

[Tunn11]

I'm sure there were many things contributing to the start-up of life, probably much more than we know.
But it's interesting about the meteorite explanation, which would mean that many planets could be teeming with all sorts of life?

If tidal forces were necessary it would cut the odds. If Venus had a moon the size of ours, life may have started and tectonics may have shifted the volcanoes.

 

[Ascalon]

This is an absolutely fascinating piece that argues that certain geological tendencies to form microtubes, combined with heat and chemical gradients may have been key to the formation of, and later combintation of, the building blocks of life.

Our chemical Eden*​

To figure out the origin of life might take a conceptual shift towards seeing it as a pattern of molecular energy

Via Aeon.co




*I think I have album somewhere. Bangin' tunes.