From RICE UNIVERSITY: Earth’s carbon points to planetary smashup
Element ratios suggest Earth collided with Mercury-like planet
CREDIT A. Passwaters/Rice University based on original courtesy of NASA/JPL-Caltech at http://www.nasa.gov/multimedia/imagegallery/image_feature_1454.html
HOUSTON — (Sept. 5, 2016) — Research by Rice University Earth scientists suggests that virtually all of Earth’s life-giving carbon could have come from a collision about 4.4 billion years ago between Earth and an embryonic planet similar to Mercury.
In a new study this week in Nature Geoscience, Rice petrologist Rajdeep Dasgupta and colleagues offer a new answer to a long-debated geological question: How did carbon-based life develop on Earth, given that most of the planet’s carbon should have either boiled away in the planet’s earliest days or become locked in Earth’s core?
“The challenge is to explain the origin of the volatile elements like carbon that remain outside the core in the mantle portion of our planet,” said Dasgupta, who co-authored the study with lead author and Rice postdoctoral researcher Yuan Li, Rice research scientist Kyusei Tsuno and Woods Hole Oceanographic Institute colleagues Brian Monteleone and Nobumichi Shimizu.
Dasgupta’s lab specializes in recreating the high-pressure and high-temperature conditions that exist deep inside Earth and other rocky planets. His team squeezes rocks in hydraulic presses that can simulate conditions about 250 miles below Earth’s surface or at the core-mantle boundary of smaller planets like Mercury.
“Even before this paper, we had published several studies that showed that even if carbon did not vaporize into space when the planet was largely molten, it would end up in the metallic core of our planet, because the iron-rich alloys there have a strong affinity for carbon,” Dasgupta said.
Earth’s core, which is mostly iron, makes up about one-third of the planet’s mass. Earth’s silicate mantle accounts for the other two-thirds and extends more than 1,500 miles below Earth’s surface. Earth’s crust and atmosphere are so thin that they account for less than 1 percent of the planet’s mass. The mantle, atmosphere and crust constantly exchange elements, including the volatile elements needed for life.
If Earth’s initial allotment of carbon boiled away into space or got stuck in the core, where did the carbon in the mantle and biosphere come from?
“One popular idea has been that volatile elements like carbon, sulfur, nitrogen and hydrogen were added after Earth’s core finished forming,” said Li, who is now a staff scientist at Guangzhou Institute of Geochemistry, Chinese Academy of Sciences. “Any of those elements that fell to Earth in meteorites and comets more than about 100 million years after the solar system formed could have avoided the intense heat of the magma ocean that covered Earth up to that point.
“The problem with that idea is that while it can account for the abundance of many of these elements, there are no known meteorites that would produce the ratio of volatile elements in the silicate portion of our planet,” Li said.
In late 2013, Dasgupta’s team began thinking about unconventional ways to address the issue of volatiles and core composition, and they decided to conduct experiments to gauge how sulfur or silicon might alter the affinity of iron for carbon. The idea didn’t come from Earth studies, but from some of Earth’s planetary neighbors.
“We thought we definitely needed to break away from the conventional core composition of just iron and nickel and carbon,” Dasgupta recalled. “So we began exploring very sulfur-rich and silicon-rich alloys, in part because the core of Mars is thought to be sulfur-rich and the core of Mercury is thought to be relatively silicon-rich.
“It was a compositional spectrum that seemed relevant, if not for our own planet, then definitely in the scheme of all the terrestrial planetary bodies that we have in our solar system,” he said.
The experiments revealed that carbon could be excluded from the core — and relegated to the silicate mantle — if the iron alloys in the core were rich in either silicon or sulfur.
“The key data revealed how the partitioning of carbon between the metallic and silicate portions of terrestrial planets varies as a function of the variables like temperature, pressure and sulfur or silicon content,” Li said.
The team mapped out the relative concentrations of carbon that would arise under various levels of sulfur and silicon enrichment, and the researchers compared those concentrations to the known volatiles in Earth’s silicate mantle.
“One scenario that explains the carbon-to-sulfur ratio and carbon abundance is that an embryonic planet like Mercury, which had already formed a silicon-rich core, collided with and was absorbed by Earth,” Dasgupta said. “Because it’s a massive body, the dynamics could work in a way that the core of that planet would go directly to the core of our planet, and the carbon-rich mantle would mix with Earth’s mantle.
“In this paper, we focused on carbon and sulfur,” he said. “Much more work will need to be done to reconcile all of the volatile elements, but at least in terms of the carbon-sulfur abundances and the carbon-sulfur ratio, we find this scenario could explain Earth’s present carbon and sulfur budgets.”
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The research was supported by NASA and the National Science Foundation.
If only this collision hadn’t happened, we wouldn’t have that terrible “carbon pollution” that environmentalists wail about today.
And everyone dismissed Velikovsky as a nut case. This sounds to me very similar to his worlds in collision theory. Is this going to turn out to be another case of someone getting rubbished and ridiculed only to find out long afterwards their ideas had some justification after all?
Please note, I am not supporting Velikovsky’s theory, simply pointing out a surprising similarity. I also note an earlier comment in this thread pointing out that Venus has a lot of carbon (mainly in its atmosphere) so I guess it might be plausible that in a close encounter some of that carbon got transferred to Earth.
First off, Velikovsky is a nut case. His date for this collision was off by about 4 billion years. If it had been correct, the earth would still not have cooled off enough to reform a solid crust.
Off topic.
Anthony – you are advertising this product on the site.
https://www.amazon.com/dp/B01EUEIL3E?ref=aap_7528418470701&me=ATVPDKIKX0DER
Soylent Green next? 🙂
Nibiru!?
Is there any data that shows that life couldn’t have started here on Earth?
Tom,
No. It’s just that it arose rapidly enough that some serious scientists have proposed panspermia as real possiblity.
Since all the constituent components of life exist in meteorites, plus water ice, it’s not outside the realm of possibility that they also delivered simple organisms to earth. Or that life got started on Mars and arrived here from there, as per the “nanobes”, allegedly nanobacteria, found in the Martian rock collected on the Antarctic ice sheet.
Panspermia moves timing and locus of life’s origins, but not the several fundamental conundra. The only hypothesis that does is Cairn-Smith’s clay hypothesis. The shoet version still available at Amazon as an ebook.
Ristvan,
The eutectic phase of ice is a more probable cradle for life than clay soils on earth, which means it could have happened just as easily in space as on our planet. Not that the two incubators are mutually exclusive.
In fact, mixing some minerals in with the RNA components in water pockets within ice would speed up the prebiotic reactions.
Experiments and discoveries in this century have greatly advanced understanding of the origin of life. The RNA World hypothesis has gained a lot of support, but has also undergone refinement. I hesitate to use the word “consensus”, but there is an emerging trend from various lines of research toward an RNA-peptide world rather than RNA alone. This despite the fact that RNA has the wonderful ability to act both as a storehouse of genetic information and as an enzyme (ribozymes), thus serving both in replication and metabolism.
In time, DNA replaced RNA in the info storage function. Meanwhile, proteins (long amino acid polymer chains) took over from short peptides (oligomers of a few amino acids) the enzymatic and structural work. RNA maintained its role in translating the genetic code into instructions for making proteins and in actually assembling them in the ribosome, which is 2/3 RNA and 1/3 protein, but its active core is RNA.
A key breakthrough has been understanding the degree to which the ribosome is a ribozyme.
So, life appears to have started as RNA strands capable of both replication and catalyzing reactions, perhaps aided by peptides. It then progressed to a ribosome-like stage, then (if not previously) got encased in a lipid bilayer membrane, to create a protocell. The membrane evolved toward active transport along the lines discovered and demonstrated by Nobel Laureate Szostak’s lab, while DNA replaced RNA as the genetic info storage mechanism and proteins replaced RNA and peptides as enzymes. The evolving cell also enclosed key biochemical reactions like the Krebs Cycle.
The Last Universal Common Ancestor was thus a bacterium containing all these components, simple yet more complex than its ancestral protocell.
Anyone who doubts the reality of common descent ought to study not just the universality of the genetic code, but the ubiquity of ribosomes. Those of prokaryotes are smaller than eukaryotic ribosomes, but ours are clearly descended from those of bacteria and our closer prokaryotic relatives, archaea (except for our mitochondria, which we eukaryotes acquired symbiotically from bacteria).
Not to mention the hundreds of vital proteins which have been conserved by natural selection for billions of years. Nor the essential biochemical pathways all life on earth shares, such as the aforementioned Krebs or Citric Acid Cycle, which also has RNA at its heart.
And of course the molecular biological and biochemical evidences for common descent and evolution only reinforce the older anatomical, organismal, biogeographical, embryological and other lines of evidence for these scientific facts.
Hubble is really an exiting quest. Thx.
The Earth formed from the same dust gas and rock cloud that the rest of the solar system formed in.
Why does everything important have to come from “outside” of that formation process and “outside” of the early Earth.
Stick some hydrogen and some oxygen in a newly forming planetoid called Earth and what do you get. Yes, you guessed it – water. Why? Because hydrogen loves its oxygen and strongly bonds with it so that it is a stable molecule for tens of billions of years. Any hydrogen coming into contact with oxygen in the gas/dust clouds forms water within milliseconds. And then it stays that way for billions upon billion of years (give or take a few that get hit by a stray ion or x-ray or gamma ray).
Carbon? Well the dust/rock cloud that formed the solar system was made up from several/dozens of previous supernova stars. All the heavy metals like uranium in the solar system prove that point. The gas/dust cloud was made by or added to by several or dozens of supernovas which occurred in the last 12 billion years or so Those supernova stars went through stages where Carbon was forming in the core furiously, and even after the supernova, huge amounts of Carbon atoms remained in the outward exploded supernova remnant. If the star does not get to supernova stage, the Carbon remains inside the now white dwarf star for the next trillion years. Carbon comes from supernova stars as well as uranium as well every other element beyond lithium.
It was all here long ago. Another planetoid hit the early smaller-sized Earth about 4.4 billion years ago, but the early Earth had all the elements that we have now. The gas cloud was probably a light year across while the rings forming planetoids are minescule compared to that. There is no way Carbon was favoured in one planetoid versus another in this huge gas/dust cloud collected together into a very small space by gravity..
The water did not come from comets and asteroids only, it was here already. The Carbon, the Iron and the Uranium was already here. The early Earth lost some hydrogen and some helium but everything else is still here. The radioactive elements which have less than 100 million year half lives are gone having radiated into other elements but everything else is still here or on the moon.
Bill,
Water on early, molten earth’s surface was lost to space, as it was on Venus. Clearly, the crust was also impoverished of C, since that element is now such a minor portion of it.
Molten Carbon reached escape velocity how exactly?
Several thousand tons probably reached escape velocity through asteroid impacts but that leaves 99.9999% still here. Carbon does not transmute into other elements except inside of large stars.
C is a tiny fraction of earth’s crust, despite being common in the universe. It went somewhere.
The C didn’t reach escape velocity. It sank into the core. Or so it seems.
Dogmatic speculation masquerading as science continues to run rampant:
Undirected Evolution: The False Religious Dogma Strangling True Science
Heh. “Irreducible complexity iiiiin SPAAAAAAAAACE!” 🙂
…And where in hell did the other planet get all that carbon?
Being small, it was supposedly as yet less differentiated than the proto-earth, whose C had descended into the core and/or mantle. As with my reply to the estimable Dr. Illis, I’m merely restating the hypothesis.
Carbon is around and about……it’s the 4th most abundant element in the universe [or what we know of it]
From Wikipedia…
According to current physical cosmology theory, carbon is formed in the interiors of stars by the collision and transformation of three helium nuclei. When those stars die as supernova, the carbon is scattered into space as dust. This dust becomes component material for the formation of second or third-generation star systems with accreted planets.The Solar System is one such star system with an abundance of carbon, enabling the existence of life as we know it.
OMG! Panspermia meets Velikovski.
One little problem though. If life came from outspace, how did it get into outer space?
It’s turtles all the way down..
https://en.wikipedia.org/wiki/Turtles_all_the_way_down
Ed Zuiderwijk,
“If life came from outspace, how did it get into outer space?”
According to the panspermacist Richard Duh-kins it would have to be consistent with his view of evolution, by some natural process that didn’t work here on earth…that MUST have worked somewhere, somehow, regardless of the total absence of a hint of scientific evidence that there is life anywhere else. See “Science”. It has all the right answers for ya if you just ask the right scientismist..
Ed, the first rule of scientismist investigation is: 1) don’t ask questions, the priests of scientism have it all worked out. There can’t be a natural process that conflicts with their existing model, there can’t be a supernatural (above nature) action, nature that is, as of yet, not understood. The problem is you. You are too curious and therefore unsuitable for scientismist participation.
🙂
Paul, once again you misrepresent Dawkins. You’ve had this pointed out before, yet persist. Argument-by-smear does you no credit.
gary hladik and gabro have the same IP, same person… and if you look above they are having a fake conversation….
We are not the same person. I don’t know how we could possibly have the same IP address.
In comment after comment you show yourself a liar. I would urge you to seek exorcism of the demon which possesses your soul, making you bear false witness against men and blaspheme your God, whom you charge with being deceptive, cruel and incompetent.
“gary hladik and gabro have the same IP, same person…”
YESSSS! Thank you, Thor, mighty god of thunder! I am now officially the subject of a conspiracy theory! Or rather, only half the subject (or AM I?), but that’s good enough for me! O frabjous day!
I gotta admit, at times I almost lost hope. All those hours of surfing the web, commenting here, commenting there, looking for just the right combination of controversial subject and gullible/paranoid commenters, and…nothing. But now…IT WAS WORTH IT!
Hey, maybe now Ben Stein will make a conspiracy documentary about me, too! Alright, Mr. Stein, I’m ready for my closeup:
I’m with Paul on this one.
First, natural mutation occurs through the effects of ionizing radiation in the environment (terrestrial radioactivity, cosmic rays). In other words, it is RADIATION DAMAGE. There have been fruit fly mutations produced this way, and they are all ugly and come to a bad end. So, this is no mechanism to “improve” any species.
Second, there is no natural selection. If mutations are supposed to be gradual, then the first mutagenic step is so small, it is swamped by NATURAL VARIATION. There is no selection in nature; everything thrives. Have you ever perused an encyclopedia of biology? The most prolific form of life on the planet is bacteria, but why does humanity exist? So we can argue that natural selection drives in the direction of proliferation?
“Natural selection” is considered a spontaneous process, but it is tantamount to the collection of information out of sheer noise. It is like a drunkard’s walk, where the drunkard somehow becomes sober. In a word, it is impossible according to information theory (which is simply a subset of thermodynamics). (This is not to say that entropy-reducing processes don’t exist in nature, but one is obliged to point out exactly what the mechanism is, such as ice caves formed by natural refrigeration of air gusts through a narrow passage.)
Dismissing Darwinism is NOT the same thing as dismissing evolution. Only a Darwinist would think so. I can open a coffee table book on automobiles and flip the pages to observe the evolution of the Pontiac brand of cars from first appearance to extinction. It may rightfully be called an evolution. But what is really going on? There is something to be said for Lamarckian evolution, for example.
The Darwinist implores the universe, “Give me a cell, and everything will begin!”
And the universe replies, “Ask in the name of God.”
“First, natural mutation occurs through the effects of ionizing radiation in the environment…”
That’s overly simplistic. Point mutations can also arise from chemical exposure and errors in replication. Genetic information can also be lost or added through deletions, recombination, and partial or complete gene or genome duplication.
“…it is RADIATION DAMAGE.”
It’s a chemical change. Whether it’s “damage” or not depends on circumstances. Due to redundancy in the genetic code, a base pair mutation may not even change the amino acid the codon specifies. Or it may change the amino acid at a place in the protein where several different ones would be just as good. Or the mutation may be lethal only if two copies are inherited (in humans, cystic fibrosis and sickle cell anemia, for example). Some “damage”, like that conferring antibiotic resistance on bacteria, is even beneficial.
“Second, there is no natural selection.”
Don’t be an idiot. You yourself wrote above this statement that “ugly” mutated fruit flies “come to a bad end.” If there were no selection, they’d survive. Come on, Michael, you’re smarter than this.
“There is no selection in nature; everything thrives.”
Define “thrive”. The vast majority of all species that ever lived on Earth are extinct. Even “thriving” species produce many more offspring than survive to reproduce, e.g. turtles:
” In a word, it is impossible according to information theory…”
Nope.
http://www.sciencemeetsreligion.org/evolution/information-theory.php
“I can open a coffee table book on automobiles and flip the pages to observe the evolution of the Pontiac brand of cars from first appearance to extinction.”
EXCELLENT example! Note how even a product of “intelligent design” mimics elements of the classic Darwinian process, including variation (new models & features), conservation (gasoline engine, four wheels, steering wheel, components in common with related “species”), selection (some “species” sell better than others) and eventual extinction. The Firebird didn’t just POOF! into existence in 1967, it had a long lineage behind it.
That’s why I’ve never understood why some people think “Darwinian” evolution is incompatible with theism. As far as I’m concerned, all the species that ever lived on Earth COULD have been “intelligently designed”, with the single stipulation that it was all done in a way indistinguishable from “Darwinian” evolution. Since a supernatural designer(s) can “design” any damn way it/they wants, then why wouldn’t “Darwinian” evolution be an option? Kumbaya, y’all! 🙂
Dear Gary,
1) Radiation damage IS chemical damage. This was known since the 1970s or earlier. Ionizing radiation causes hydrolysis of water molecules, and the hydroxyl free radicals recombine into hydrogen peroxide, which is a Bad Actor inside living cells. One of the reasons we are urged to take antioxidants. This hypothesis was tested by subjecting cells to hydrogen peroxide. It created all the observed signs of radiation damage. (Sometimes a cosmic ray proton will hit a biological molecule. Wipeout.)
2) Yeah, there might be tinkertoy combinations possible, but how do you explain the occurrence of the tinkertoy pieces? That should give you pause.
3) So, your proof of the existence of “natural selection” is that it kills off mutated species? Kind of defeats the Darwinian process, doesn’t it. But it is better to say that radiation exposure is life-damaging, if it exceeds the hormesis level. I mean, volcanoes happen, and we get eaten by lions. Just because EVERYTHING dies does not mean life does not flourish. Look at the huge VARIETY of living forms. What is the single common denominator that constitutes the selection principle? Height? Weight? Color? Metabolism? It is all over the map. Life is virtually everywhere (excepting portions of Antarctica, I suppose).
4) And, since everything does die, what is the meaning of “extinction”? How is it possible for “natural selection” to be on a winning jag at the Craps of Life table, and then suddenly lose the stakes? Sometimes, one species eats the population of another species. But how does this square with the premise of natural selection? We wiped out the passenger pigeon…but is humanity the big winner in the natural selection department? We, and just about any other higher form of life, are outnumbered and outmassed by bacteria. They are obviously the winner if proliferation is the measure (which is the usual example for natural selection)…which provides no explanation for why we can talk about “higher” forms of life, or even ourselves, since (according to Darwinism) there is no good reason for us to be “selected.”
5) As for information theory, reference to Dembski is beside the point. The theory originated with Claude Shannon. I’ve read (and understood) his original paper. It is not based on any silly notion that information is conserved. It IS based on the notion that information is directly representable as entropy (as defined by Ludwig Boltzmann) and vice versa (and is interpreted as that which reduces the entropy–or uncertainty–of a signal). According to this, information is prone to be lost over time and the action of randomness, or noise. Moreover, it totally precludes the emergence of information from a random equilibrium environment. Drop a bit of ink in a bucket of water; it will disperse and taint the water. Can the ink reassemble in such a way as to spell out a message? The believers in random magic will say yes, but it is flat out impossible, because to do so would be to spontaneously reduce the entropy of the water/ink combination. And this can be calculated, not just arm-waved (though the calculation is not trivial).
But there is an underlying premise: before there can be information, there must be a message (or signal). If there is no message, there is only noise. This is the miracle of life: that we depend on the accurate transmission of an exceedingly high-information-content message in order to procreate. This is not something that can be mediated by random processes.
6) The example of evolving (and extinct) Pontiacs was an example of INTELLIGENT DESIGN evolution. Without intelligence, the Pontiacs would never “evolve” beyond iron ore. Shoot all the engineers and see what does not happen. Yes, when we have intelligence at the root of things, we can see “evolution” (progression from simple forms to complex forms, or assemblage of information into a greater message)…but not when we play billiards. Or are you trying to say that intelligence is nothing other than Darwinian random events? It wouldn’t surprise me, but it would be absurd. Tell it to Beethoven.
(“Natural selection” is a bogus notion, not even a concept. “Selection” is a concept that requires (1) criteria, (2) observation, (3) judgment, and (4) enforcement. To refer to “natural” selection is, at best, a figure of speech; it does not involve the literal concept of selection.)
7) The funny thing about all this is that I, personally, take the view that the random process is “God’s auto-pilot.” it is perfectly reliable and predictable when at the scale of large ensembles (e.g., kinetic theory of gases). You can turn your back on it with perfect confidence. But it can’t assemble a living cell…and that’s what Darwinism requires for a starting point. It turns out that a living cell is a tough cookie to justify by randomness.
Full disclosure: I’m not speaking as an enthusiast. I’ve been trained and work in this field.
“Radiation damage IS chemical damage.”
Yup, but you explicitly linked it to mutation, and mutation by radiation or other means is not always “damage”, as I illustrated. If you want to discuss chemical “damage” per se, leave mutation out of it.
“…how do you explain the occurrence of the tinkertoy pieces?”
If you’re referring to abiogenesis, take it up with Gabro–my alter ego, according to Paul. 🙂
“So, your proof of the existence of “natural selection” is that it kills off mutated species?”
To be more accurate, natural selection results in “differential reproductive success”, for example when your mutated fruit flies fail to survive long enough to reproduce.
“What is the single common denominator that constitutes the selection principle?”
Why would only one trait be selected? There are many ways an organism or group of organisms can fail to reproduce as well as their competitors, as you hinted in your “VARIETY” statement.
“How is it possible for “natural selection” to be on a winning jag at the Craps of Life table, and then suddenly lose the stakes?”
Easy peasy: The species’ environment (including all the life around it) changes too fast or too drastically for the species to adapt. Maybe it’s a hundred-year drought, or maybe one of its predators (e.g. germs, hawks, “cavemen”) gets too good at hunting it.
“…since (according to Darwinism) there is no good reason for us to be “selected.”
And according to “Darwinism”, apparently no good reason not to be. 🙂
“[Shannon information] IS based on the notion that information is directly representable as entropy”
Popular misconception. NOT thermodynamic entropy.
http://www.talkorigins.org/faqs/information/shannon.html
In fact Shannon information theory doesn’t prove “Darwinian” evolution is impossible, which is why Dembski and other creationists have to invent bogus new “theories” of information.
Michael, here’s a common sense question I sometimes ask of pseudoscience advocates here at WUWT (for example, those who insist the so-called “greenhouse effect” is incompatible with the 2nd Law): If information theory really proved “Darwinian” evolution impossible, it would be a scientific revolution; those responsible would earn at least one Nobel Prize plus many other honors. Yet, inexplicably, mathematicians (many of them deists, according to surveys), who have no vested interest in “Darwinism”, have failed to jump on the anti-evolution bandwagon and claim their supposed rewards. WUWT?
“The example of evolving (and extinct) Pontiacs was an example of INTELLIGENT DESIGN evolution.”
Exactly my point, but I see I have to clarify. I’ll try again.
Some creationists point to a watch and say (I’m paraphrasing), “See? We know this complex thing was designed, therefore all complex things must have a designer!” Unfortunately, they miss the most important lesson of the watch, which is the long, involved, “evolutionary” process that led from celestial timekeeping to clocks to watches to atomic clocks. If they did understand that, maybe they’d see that “Darwinian” evolution isn’t in principle incompatible with deism. You know, kind of like the Pope:
http://www.usatoday.com/story/news/world/2014/10/28/pope-francis-evolution-big-bang/18053509/
“Selection” is a concept that requires…”
Nope. No intelligence required. A desert tends to select, in the “Darwinian” sense, for organisms that manage water differently than organisms living in a jungle. Bubonic plague “selects” for humans resistant to it (see Jared Diamond’s Guns, Germs, and Steel. Note, however, that non-human “intelligence” may operate; for example lions tend to “select” the slowest/weakest members of a herd. And sometimes it’s just dumb luck, as in that sea turtle video I linked: the babies escaped predatory seagulls because humans happened to be present.
“…the random process is “God’s auto-pilot.”
If you include non-random natural selection in your autopilot, the Pope says you’re good to go! 🙂
Michael,
Those of us working in synthetic biology and directed evolution actually use evolution to develop and improve the enzymes and other chemicals which we discover to treat diseases and improve the environment.
In this century, we’ve found out that it’s more cost-effective to let evolution find the macromolecules we want, rather than trying to design them, which involved, guessing, trial and error.
https://www.newscientist.com/article/mg21028181-700-evolution-machine-genetic-engineering-on-fast-forward/
Speaking of the origin of cells, a recent breakthrough by the Scripps team, which I cite in these comments, was achieved using just these tools and techniques, ie the same way that cells first arose, via selection operating on hundreds of trillions or more competing molecules and biochemical processes.
Even the simplest modern cells are indeed complex. But the first cells, as I’ve written above, weren’t. And before them was extracellular life. The simplest form of life will soon be made in a lab in America, Europe or Asia. That would be a strand of RNA capable of acting both as a storehouse of genetic information, ie in replication, and as an enzyme, ie in metabolism, such that it can reproduce itself through endless cycles and evolve. These capabilities define life.
The Scripps team has showed that RNA alone is capable of replicating itself with the same mechanisms it uses to assemble amino acids into peptides, the bulding blocks of proteins. IOW, it can assemble nucleotides and bond them together to make an RNA copy of itself in the same way that it assembles and bonds amino acids to make peptides and polypeptides, ie proteins.
Other researchers have concluded that the development of life from prebiotic near-life required the cooperation of peptides (precursors of today’s protein enzymes) and RNA. And that may indeed have been how life arose. But the recent Scripps result, achieved thanks to evolution machines, shows that RNA might have sprung into life all on its own.
The functioning and structure of ribosomes, the protein factories in every cell, reinforce this conclusion. In 2000 a Yale researcher discovered that the active part of the large subunit of the ribosome is all RNA, although the whole ribosome is a third protein. Last year, workers further showed that ribosomal RNA consists of transfer RNA. The most parsimonious explanation for this fact is that the ribosome is a big ribozyme (RNA with enzymatic function). Hence the first living things were the ancestors of transfer RNA.
A young lady researcher also recently showed that a ribozyme could be as short as an oligomer of only five nucleobases.
The lipid bilayer membrane came later. Lipid bilayers, like RNA, self-assemble in water. The trick is getting RNA to grow before the nucleotide bonds dissolve. The Scripps team has shown that RNA can promote its own polymerization. But it needs more runs through the evolution machine to improve this enzymatic function even more. Then, Bingo! Life!
Maybe you have to work with RNA to appreciate what a powerful molecule it is.
Even short, ephemeral strands of it, like the pentamer I mentioned, are pregnant with life.
The theory that the moon is the result of a collision between a Mars sized planet and the Earth, right about the same time, has gained wide acceptance.
Oh, well. I have to put in a word for the “hydridic Earth” hypothesis of Vladimir Larin (see https://www.amazon.com/Hydridic-Earth-Geology-Primordially-Hydrogen/dp/0969450621).
Synopsis: The Earth condensed from a composition of elements that were mostly hydrides (lots of hydrogen available). Hydrides can be compressed to higher densities than elemental metals, so our core consists of such hydrides. Heat, as from natural radioactivity (or maybe a natural uranium reactor), causes the breakdown of the hydrides into hydrogen and base elements. The hydrogen migrates upward through the core and mantle. Along the way, it reduces oxygen to water, nitrogen to ammonia, sulfur to hydrogen sulfide, phosphorous to phosphine, and carbon to methane, and brings them all to the crust through vulcanism. There are other implications, but all this is very intriguing.
He is no crank and he tests his hypothesis against terrestrial geology and the known “geology” of the Moon.
I agree that we must exercise reserve when pondering ideas that are presented simply because the idea’s creator could think of no better idea. That’s a pretty conceited basis for speculation, once you think about it.
While I find evidential support for/against the Giant Impact Theory of the moon’s formation, I can’t say this qualifies. This is based on an argument ad ignorantium: “we don’t know how the earth could have had it’s own carbon supply, so it must have come from somewhere else.” There is no *evidence* for the compositions of the Proto-Earth or of the Theia (the giant impact body) yet. This is all pure speculation at this point. Show me at least a carbon budget and prove it could not have come from cometary masses such as what Philae found on Comet 67B: 20% carbon-containing compounds.
More money well spent on a pointless “could” effort.
But but the solar system has been stable.. yadda yadda.
All the clues say the solar system was anything but stable. If everyone really believes all holes on all solar system bodies are crater impacts, then ask yourselves why they all seem to be strikes from directly above, relatively very few scraping impacts, there should be far more of those types.
I mean, Mars has one huge scorch mark across it, couldn’t be more obvious.
“… then ask yourselves why they all seem to be strikes from directly above, relatively very few scraping impacts…”
First result of a Google search:
http://www.scientificamerican.com/article/why-are-impact-craters-al/
Sumerians (about 6,000 years earlier) apparently knew about this & was found brought forward in Babylonian text “Epic of Creation” that was ritually read every spring. Pre- collision earth was called in Sumerian “Tiamat” (called “Tehom” in Babylonian epic) & after being struck (by what Sumerians called “Nibiru”, translated into English = “planet of the crossing”) parts broke off to form an asteroid belt, our moon & our earth (called “Ki” in Sumerian”). The epic specified “Nibiru” (in Babylonian version called “Marduk” due to revamped pantheon of the gods from Sumerian civilization) brought the “seed of life.”
Nibiru was made up by ancient astronaut advocate Sitchin. It’s not Sumerian.
https://en.wikipedia.org/wiki/Zecharia_Sitchin
Tiamat was the Mesopotamian goddess of the ocean, who mated with Abzu, the god of fresh water, to produce the generation of younger gods.
Genesis 1, the first of the two creation myths in the first book of the Bible, is based upon this Sumerian story, as filtered through Babylon, Assyria and Canaanites in Ugrit.
Gabro,
“Genesis 1, the first of the two creation myths in the first book of the Bible, is based upon this Sumerian story, as filtered through Babylon, Assyria and Canaanites in Ugrit.”
Or, you believed some stuff some people figure, but is not so.
If the story in Gen 1 were true, then is it not perfectly expectable that stories such as we can see from those other sources would exist, and bear at least some vague resemblance to it? If the Gen 1 account is true, it would be kinda unbelievable that no one who survived would tell stories about what happened to their kids, and those stories would not then echo through time in some form . . to me anyway. What we can see is actually rather consistent with what the Book presents, therefore, right?
I meant those who survived the great flood . . would tell such stories . .
Maybe our carbon came from the georeactor at earth’s inner core. That would explain the carbon, and many other things.
There is a theory that our moon, before it was the “moon”, collided with the Earth billions of years ago. That would account for the mineral exchange.