Uncommon Descent Serving The Intelligent Design Community

At Science Daily: Fossil overturns more than a century of knowledge about the origin of modern birds

Share
Facebook
Twitter
LinkedIn
Flipboard
Print
Email

Fossilised fragments of a skeleton, hidden within a rock the size of a grapefruit, have helped upend one of the longest-standing assumptions about the origins of modern birds.

Researchers from the University of Cambridge and the Natuurhistorisch Museum Maastricht found that one of the key skull features that characterises 99% of modern birds — a mobile beak — evolved before the mass extinction event that killed all large dinosaurs, 66 million years ago.

This finding also suggests that the skulls of ostriches, emus and their relatives evolved ‘backwards’, reverting to a more primitive condition after modern birds arose.

Using CT scanning techniques, the Cambridge team identified bones from the palate, or the roof of the mouth, of a new species of large ancient bird, which they named Janavis finalidens. It lived at the very end of the Age of Dinosaurs and was one of the last toothed birds to ever live. The arrangement of its palate bones shows that this ‘dino-bird’ had a mobile, dexterous beak, almost indistinguishable from that of most modern birds.

For more than a century, it had been assumed that the mechanism enabling a mobile beak evolved after the extinction of the dinosaurs. However, the new discovery, reported in the journal Nature, suggests that our understanding of how the modern bird skull came to be needs to be re-evaluated.

Each of the roughly 11,000 species of birds on Earth today is classified into one of two over-arching groups, based on the arrangement of their palate bones. Ostriches, emus and their relatives are classified into the palaeognath, or ‘ancient jaw’ group, meaning that, like humans, their palate bones are fused together into a solid mass.

All other groups of birds are classified into the neognath, or ‘modern jaw’ group, meaning that their palate bones are connected by a mobile joint. This makes their beaks much more dexterous, helpful for nest-building, grooming, food-gathering, and defence.

“This assumption has been taken as a given ever since,” said Dr Daniel Field from Cambridge’s Department of Earth Sciences, the paper’s senior author. “The main reason this assumption has lasted is that we haven’t had any well-preserved fossil bird palates from the period when modern birds originated.”

Two of the key characteristics we use to differentiate modern birds from their dinosaur ancestors are a toothless beak and a mobile upper jaw. While Janavis finalidens still had teeth, making it a pre-modern bird, its jaw structure is that of the modern, mobile kind.

“Evolution doesn’t happen in a straight line,” said Field. “This fossil shows that the mobile beak — a condition we had always thought post-dated the origin of modern birds, actually evolved before modern birds existed. We’ve been completely backwards in our assumptions of how the modern bird skull evolved for well over a century.”

The researchers say that while this discovery does not mean that the entire bird family tree needs to be redrawn, it does rewrite our understanding of a key evolutionary feature of modern birds.

Full article at Science Daily.

Assumptions seem to have played a large role in the evolutionary story of birds. When assumptions turn out to not match reality, then either the theory is wrong, or extrapolations made from the theory are unjustified.

Comments
All, Coincidentally, this wide-ranging and mind-blowing interview/conversation at a conference between chemist Dr. James Tour and cosmologist Dr. Brian Keating was posted a few hours ago. Did Aliens Seed Life on Earth? Dr Tour & Astrophysicist Brian Keating on Science, Faith & Evolution https://www.youtube.com/watch?v=gIhzqMQSIzc It's well worth watching. I learned several new things and I loved it! -QQuerius
December 14, 2022
December
12
Dec
14
14
2022
08:58 AM
8
08
58
AM
PST
Asauber @93,
PyrrhoManiac1: Did the Holocaust happen? Do we know what caused the French Revolution? What led up to the Peloponnessian War?” Asouber: These attempted diversionary questions have no relevance to my point. BUZZZZT! Wrong!
Exactly! This is an attempt to create a parallel or an analogy between historical human events over the past several thousand years and an extrapolation of evolution for up to about 4 billion years. This is time factor of about a million to one in the case of the OOL problem. Human history is replete with human witnesses, interlocking histories, and artifacts, while there are no human witnesses to the OOL and subsequent evolution. Even changing the analogy to hypothesizing that the Greek gods had corporeal existence, is not an equivalent extrapolation. After watching James Tour's videos, the incredible speed attributed to the origin of life, and the probable environmental conditions of the earth and its atmosphere, I'd agree with Alan Fox that an extraterrestrial source for life on earth is far less complex and far more plausible for the simple reason that planets in other solar systems had far more time available, commonly accepted to be about 13.8 billion years, a factor of 3 times as long. If it took about a half billion years for life to evolve on earth, which is commonly accepted among researchers in the subject, then intelligent extraterrestrial life among billions and billions of stellar systems has had about 13 billion years MORE time to develop into something that could locate and seed suitable planets such as the earth with a massive spectrum of life forms. It seems like a mathematical slam dunk that life on earth was seeded by an unknown agent or agents. -QQuerius
December 13, 2022
December
12
Dec
13
13
2022
05:55 PM
5
05
55
PM
PST
"Why are they irrelevant?" PM1, Different issues. The issue is Imaginary Evolution. Stick to the issue. Andrewasauber
December 13, 2022
December
12
Dec
13
13
2022
12:40 PM
12
12
40
PM
PST
@93
These attempted diversionary questions have no relevance to my point. BUZZZZT! Wrong!
Why are they irrelevant?PyrrhoManiac1
December 13, 2022
December
12
Dec
13
13
2022
12:36 PM
12
12
36
PM
PST
"Did the Holocaust happen? Do we know what caused the French Revolution? What led up to the Peloponnessian War?" PM1, These attempted diversionary questions have no relevance to my point. BUZZZZT! Wrong! Andrewasauber
December 13, 2022
December
12
Dec
13
13
2022
12:34 PM
12
12
34
PM
PST
@91
Which makes it entirely imaginary. A fantasy about the past. *POOOOOOOOF*
Did the Holocaust happen? Do we know what caused the French Revolution? What led up to the Peloponnessian War? If you think that historians can answer those questions, what's the criterion that leads you to put historians in one category and archeologists and paleontologists in a different category?PyrrhoManiac1
December 13, 2022
December
12
Dec
13
13
2022
12:21 PM
12
12
21
PM
PST
“Macro-evolution” is accumulation of small evolutionary steps over up to four billion years." Which makes it entirely imaginary. A fantasy about the past. *POOOOOOOOF* Andrewasauber
December 13, 2022
December
12
Dec
13
13
2022
12:16 PM
12
12
16
PM
PST
Alan Fox @86,
Querius: What’s not observed is the macroevolution of novel features… Alan Fox: Well, of course not. “Macro-evolution” is accumulation of small evolutionary steps over up to four billion years.
And this is the magician’s cape draped over macroevolution, which has not been observed but extrapolated contrary to both the fossil record and the limited DNA analysis that’s been done (and NOT applied to taxonomies for the most part). The counter-argument is that evolution has NOT magically stopped, so it MUST be the case that among the billions and billions of organisms on earth right now, many are in process of evolution considering slow environmental changes including ALL features in stages of evolutionary change and MANY novel features must be occurring in hundreds of organisms. So where is the current evidence for contemporary recurrent evolution? Are there any mice that are starting to develop wings or becoming aquatic by developing gills? Adaptation but not any NEW features https://phys.org/news/2020-10-species-aquatic-mice-cousins-world.html Back to Origin of Life, James Tour just released this video devastating current science fantasy: https://youtu.be/aUOZh4zmrXo Again, his primary point is that current OOL hypotheticals are grossly inadequate. We shouldn’t exaggerate by claiming “while we don’t yet have all the precise details,” but rather be honest in admitting “we are completely clueless.” Honest admissions of ignorance are the first step in advancing scientific knowledge. Collecting unprejudiced, unfiltered observations and data are a second step. Anything else is puffery and dogmatism. -QQuerius
December 13, 2022
December
12
Dec
13
13
2022
10:54 AM
10
10
54
AM
PST
AF, predictable, and predictably failed. Take wings for instance, said to have separately evolved four times: arthropods, reptiles, birds, bats. You need not only aerodynamics and all sorts of coordinated body changes but motors, nerve controls, brain wiring plus underlying metabolic and genetic structures far beyond 500 - 1,000 bits of complexity. You are resorting to poof magic, information and organisation from nowhere on claims about niches and incrementalism. Flight is brutally, lethally exacting and demands fine tuned function. The problem is you have to first get to fine tuned shorelines of function before hill climbing can even begin. This and many other glided over issues -- and the hostility to those who point them out -- tell us we are looking at ideologically driven just so stories pronounced in a posh accent while dressed in a lab coat. KFkairosfocus
December 13, 2022
December
12
Dec
13
13
2022
02:38 AM
2
02
38
AM
PST
blockquote>...no mechanisms adequate to account for blind force body plan level transformations have been actually observed. HOX genes are a powerful piece of circumstantial evidence which bolster the fossil record.Alan Fox
December 13, 2022
December
12
Dec
13
13
2022
12:16 AM
12
12
16
AM
PST
AF, what is more to the point is, no mechanisms adequate to account for blind force body plan level transformations have been actually observed. Newton's rules obtain. KFkairosfocus
December 13, 2022
December
12
Dec
13
13
2022
12:09 AM
12
12
09
AM
PST
What’s not observed is the macroevolution of novel features...
Well, of course not. "Macro-evolution" is accumulation of small evolutionary steps over up to four billion years.Alan Fox
December 12, 2022
December
12
Dec
12
12
2022
10:42 PM
10
10
42
PM
PST
P.S.
Extinction is both a loss and an opportunity. I see space left by broken teeth as previously-occupied empty niches that allow existing neighbouring species to exploit. Chicxulub was a disaster for dinosaurs but an opportunity for cynodonts.
Or encroachment by neighboring species in a global Survival World Cup that selects for adaptability over long periods of time. Here's a great example. Panthera tigris has become so specialized that its variability is almost nil. This alone is sufficient to make it a candidate for extinction in the face of inevitable environmental changes. Similarly, Wheat has become such an agricultural monoculture that a single pathogen could wipe out all wheat. This is why seed banks for obscure varieties of wheat have been established. The threat is as real as the Irish Potato Famine and banana extinction. Here's an excellent article on the subject: https://ourplnt.com/bananas-extinction/ -QQuerius
December 12, 2022
December
12
Dec
12
12
2022
02:49 PM
2
02
49
PM
PST
Alan Fox @83,
Distinguishing between micro and macro evolution is unnecessary and misleading.
I disagree. Microevolution HAS BEEN OBSERVED in the disabling of certain features for a survival benefit. There are many instances of this. For example - Wing loss of insects on windy islands - Sickle cell mutation in humans to combat malaria - Eye loss in cave fish However, epigenetic changes in Darwin's finches between large and small beaks in a single generation is built-in genetic programming for adaptability. What's not observed is the macroevolution of novel features, biochemical improvements, or dare I say, new body plans along the lines of Echinodermata with a hydrostatic vascular system functioning for locomotion, predation, and respiration (and they also have pincers to move food along their body surface to their mouth). This combination of features is so unusual, one might think they were aliens. What's not known about Echinoderata is as fascinating as what is known: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3308324/ What becomes apparent is that some elements in Echinoderata are considered "primitive" (lack of blood cells, light-sensitive eye spots) while other elements are considered "advanced" (DNA, immune system with factors found only in vertebrates and chordates). To an unbiased scientific observer, such variety of characteristics seem like a Frankenstein of features. To put it another way, I could imagine alien AI/robotic entities finding a destroyed planet earth having intense arguments over whether motorcycles evolved from cars or cars evolved from motorcycles based on their design features. This is why microevolution and macroevolution are often considered separately (as is abiotic OOL). -QQuerius
December 12, 2022
December
12
Dec
12
12
2022
02:22 PM
2
02
22
PM
PST
@ Querius (81) That's a lot to respond to so let me initially pick up on a couple of points that stood out as needing a reply. Distinguishing between micro and macro evolution is unnecessary and misleading. Evolution (involving sexual reproduction) can only occur in steps small enough so that reproductive isolation of an individual does not prevent those genes spreading through a population. Macroevolution does not involve additional processes, only more time. Regarding the comb analogy, it misses an important point if your teeth represent populations of species sharing a planetary environment. Extinction is both a loss and an opportunity. I see space left by broken teeth as previously-occupied empty niches that allow existing neighbouring species to exploit. Chicxulub was a disaster for dinosaurs but an opportunity for cynodonts.Alan Fox
December 12, 2022
December
12
Dec
12
12
2022
12:07 AM
12
12
07
AM
PST
Incidentally, you have a very nicely written and reasonable article on the subject! Yes, this is a compliment.
Thank-you. Much appreciated.Alan Fox
December 11, 2022
December
12
Dec
11
11
2022
11:41 PM
11
11
41
PM
PST
Alan Fox, As another alternative to a non-terrestrial OOL scenario, let’s speculate that (1) the earth was seeded from an unknown extraterrestrial source with a complete spectrum of life forms early on. Let’s also speculate that (2) micro but not macro evolution took place for millions of years. And finally, let’s speculate that (3) there are no “primitive” features or simpler, less-evolved organisms, just different ones. Considering what’s actually OBSERVED in fossil strata, what would you expect to support these speculative assumptions? Here’s my list: 1. Rapid appearance of all major body plans without evidence of a common origin (Cambrian). 2. A plethora of fossils of extinct organisms among contemporary ones (or nearly so, considering microevolution). 3. Mass extinctions tied to catastrophic events such as floods or tsunamis, meteorite impacts, "supervolcanoes (https://www.sciencealert.com/new-study-suggests-the-threat-of-supervolcano-eruptions-lingers-for-thousands-of-years), and the resulting climate change. 4. A lack of smooth sets of “transitional” forms, since there were no significant transitions, only extinctions. As an analogy, think of the teeth in a massively long comb arranged from smallest to largest teeth. Then, randomly break off 99% of the teeth as extinctions. 5. “Living fossils” that mysteriously survived. Any observed fossils, if reconstructed could conceivably survive on earth today. For example, consider trilobites versus triops: http://www.arizonafairyshrimp.com/triops.html 6. Fossil beds with many mixed and disarticulated remains, coal seams, animals killed during birth or during predation, and fossils in death poses identical to those in drowned chickens. 7. Out-of-place fossils and polystrate fossils. To the contrary, what’s actually OBSERVED in fossil strata that weakens the speculation? 1. -QQuerius
December 11, 2022
December
12
Dec
11
11
2022
07:07 PM
7
07
07
PM
PST
P.P. Did you have a chance to view the 10-minute Sabine Hossenfelder interview? Even though she holds a deterministic materialism worldview, I respect her not trying to cover up the current problems with the "standard model" of physics, fine tuning, the multiverse, and the role of improbabilities. This interview has to do with the Anthropic principle applied to a speculated multiverse and the problem of the unlikelihood of fine-tuning (or the chance hypothesis of the OOL). Sabine Hossenfelder - What's the Deep Meaning of Probability? https://www.youtube.com/watch?v=XVNtM0XFTaE -QQuerius
December 11, 2022
December
12
Dec
11
11
2022
06:24 PM
6
06
24
PM
PST
Alan Fox @78,
Then he asserts too much. “Origin-of-Life” ideas are not yet testable hypotheses.
I think what Dr. Tour is pointing out are three massive obstacles to the current crop of terrestrial hypotheses: • Racemic environment • Chemical purity and concentration of the reagents • Critical timing at each step
I risk making myself look foolish by making a prediction that OoL research will only advance when plausible evidence emerges from elsewhere than Earth.
No, I wouldn’t at all say foolish. After all, that’s what Francis Crick initially proposed. https://www.liquisearch.com/francis_crick/directed_panspermia But I’d also point out in the above article, when the author writes the following about the 1960s:
Many molecular biologists were puzzled by the problem of the origin of a protein replicating system that is as complex as that which exists in organisms currently inhabiting Earth.
When I took high school biology at the time, there wasn’t even a hint at any scientific doubt at what MUSTA happened! From the Miller-Urey experiment, it was a short hop to “coacervates,” and then it was another easy hop to coelenterates, followed by kangaroos. Absolutely NOTHING in our Biology textbook indicated any doubt that everything was well-understood. Only trivial details and refinements were left. Geology was frequently cited in support of the tree of life. Similarly, the tree of life was frequently cited in support of the geological column. I noticed this and resulted in the first cracks in my faith in Darwinian evolution. Subsequently, I noticed similar dogmatism in many of the college science courses that I took, a lot of which is no longer considered correct. Except Darwinism, of course.
For example, Mars is being studied closely. Evidence could show that Mars is incontrovertibly sterile, supporting the idea that emergence of life is rare or unique to Earth.
However, note that “The presence of moon and Mars rocks on Earth forces us to conclude that there must be Earth rocks on Mars, and such rocks could have carried primitive life to the Red Planet.” https://www.jpl.nasa.gov/news/martian-soil Thus, I don’t think it would be impossible that carved stone structures ejected from earth by meteorite impacts might eventually be found on Mars or the moon. Or remnants of once-living organisms for that matter.
For example, Mars is being studied closely. Evidence could show that Mars is incontrovertibly sterile, supporting the idea that emergence of life is rare or unique to Earth. Or we find evidence of life that suggests it had/has features that suggest relatedness to Earth life, supporting panspermia. Or we find evidence of living organisms utterly unlike Earth life, supporting life can get going anywhere there is an opportunity. http://theskepticalzone.com/wp/abiogenesis-the-second-data-point/
Currently, the odds seem to favor panspermia over a terrestrial OOL. Incidentally, you have a very nicely written and reasonable article on the subject! Yes, this is a compliment. -Q
Querius
December 11, 2022
December
12
Dec
11
11
2022
06:13 PM
6
06
13
PM
PST
And that’s exactly Dr. Tour’s position.
Excellent.
He never says we can’t know. He asserts that current OOL hypotheses are far off the mark.
Then he asserts too much. "Origin-of-Life" ideas are not yet testable hypotheses. I risk making myself look foolish by making a prediction that OoL research will only advance when plausible evidence emerges from elsewhere than Earth. For example, Mars is being studied closely. Evidence could show that Mars is incontrovertibly sterile, supporting the idea that emergence of life is rare or unique to Earth. Or we find evidence of life that suggests it had/has features that suggest relatedness to Earth life, supporting panspermia. Or we find evidence of living organisms utterly unlike Earth life, supporting life can get going anywhere there is an opportunity. http://theskepticalzone.com/wp/abiogenesis-the-second-data-point/Alan Fox
December 10, 2022
December
12
Dec
10
10
2022
11:52 PM
11
11
52
PM
PST
Alan Fox,
Querius: You can’t present and “evolve” from the previous step.
To clarify what I mean by "present," I mean "go back to an earlier version." Also pertinent to probabilities, multiverse, and fine tuning is this provocative 10-minute interview of Dr. Sabine Hossenfelder, a theoretical physicist and atheist. https://www.youtube.com/watch?v=XVNtM0XFTaE -QQuerius
December 10, 2022
December
12
Dec
10
10
2022
05:41 PM
5
05
41
PM
PST
Alan Fox @74,
You (and Tour, if this is his view) are not seeing this is a feature, not a bug.
No, not a feature, but a serious obstacle to overcome! That "time is not your friend" is precisely the view of Dr. Tour, an organic synthetic chemist whose expertise is in assembling molecules.
Nothing is a contaminant, all are ingredients.
Not if you want to get life. It's like asserting "everything in cooking is an ingredient" (poisons and dog poop immediately come to mind). I would dare say that if OOL chemistry was within our scientific grasp, Dr. Tour would be among the first to find out how. One of his more significant recent discoveries was how to convert waste plastic into graphene. Graphene has amazing applications (the strongest material known, the best heat conductor, can be used instead of lithium in batteries, etc.) but currently costs over $1,000 per Kg. See https://www.graphene-info.com/graphene-applications
Temperature is crucial but gradients occur.
Again, one has to bring components together with different temperature requirements within a limited amount of time before they fall apart. Try going to Restaurant Random (tm) where random ingredients are combined randomly from a chemistry lab and the back alley at different gradients of temperatures for different amounts of time. How long would you need to wait for a perfectly cooked dinner of your choosing, let's say beef bourguignon? Dr.Tour's point is that one has to start from scratch at each failure! You can't present and "evolve" from the previous step. Or to put it more bluntly, once there's dog poop in your beef bourguignon, you have to throw it out. Well, I would, anyway (into our compost heap, actually). -QQuerius
December 10, 2022
December
12
Dec
10
10
2022
04:09 PM
4
04
09
PM
PST
Alan Fox @73,
I go with number 6, we don't know.
And that's exactly Dr. Tour's position. He never says we can't know. He asserts that current OOL hypotheses are far off the mark. Not even close. From his scientist's point of view, we need to think outside the box. -QQuerius
December 10, 2022
December
12
Dec
10
10
2022
04:06 PM
4
04
06
PM
PST
In a prebiotic chemical environment, time is not your friend–it’s your enemy. Large organic molecules rapidly fall apart depending on temperature and tend to combine with other molecules to form polymeric “junk” that poisons the products of the reactions. Plus, your “lab” is very dirty with contaminants and temperatures are not cooperative.
You (and Tour, if this is his view) are not seeing this is a feature, not a bug. Nothing is a contaminant, all are ingredients. Temperature is crucial but gradients occur. Water emerges from thermal vents at temperatures up to around 400°C, yet the surrounding water can be near freezing. Junk is opportunity.Alan Fox
December 10, 2022
December
12
Dec
10
10
2022
02:19 PM
2
02
19
PM
PST
Take your pick.
That's not an exhaustive list. But, I'll play along. We know for sure that water-based life cannot exist without liquid water. The very early Earth's surface was initially molten rock and therefore sterile. We know it cooled enough for there for water to condense, and we know life got started not much later. So my choices are: 1, Life's origin on Earth happened on Earth due to extremely rare and fortuitous events. 2, Life's origin on Earth happened inevitably because the emergence of life is a common occurence throughout this universe. 3, Life on Earth was imported from elsewhere. 4, God (the Christian one, for argument's sake) created the universe, the Earth, and us for reasons and using supernatural power. 5, A god created the universe in such a way that life emerged on Earth without violation of the natural laws. 6, We don't know. I go with number 6, we don't know.Alan Fox
December 10, 2022
December
12
Dec
10
10
2022
02:12 PM
2
02
12
PM
PST
Alan Fox @70,
Querius: Another problem Dr. Tour points out is that in organic synthesis, “nature doesn’t keep a lab notebook.” That means if an abiotic evolutionary step is a failure, nature doesn’t get to go back a step, but rather it must start over from scratch each time. Alan Fox: The lab was the whole prebiotic Earth (or elsewhere if panspermia is evidenced by data from future or current space exploration) and maybe a billion years of trials.
Here's the problem according to another one of Dr. Tour's videos: In a prebiotic chemical environment, time is not your friend--it's your enemy. Large organic molecules rapidly fall apart depending on temperature and tend to combine with other molecules to form polymeric "junk" that poisons the products of the reactions. Plus, your "lab" is very dirty with contaminants and temperatures are not cooperative. So, where does this leave OOL researchers? It leaves them the following possibilities: 1. Life was emerged fully formed in a single incredibly improbable event. It was all luck. The problem is that this luck is so improbable that we need to hypothesize an infinite number of multiverses over an infinite amount of time to make it probable to happen somewhere. Another problem is that the existence of multiverses is not testable (thus not scientific). 2. Life originated somewhere else under completely different conditions. This still leaves open the issue of the origin of information, which hasn't been solved--we can't even define information, Shannon notwithstanding. This "somewhere else" can even be gases in space, since protein synthesis cannot occur in water. 3. Life originated from intelligent abiotic sources. Life on earth might have been a classroom project or maybe the result of a single abiotic intelligent agent. 4. We live in an ancestor or other type of computer simulation like the movie, "The Matrix" but without the brain hookups. This simulation is limited in processing speed by the speed of light. Its voxels (3D pixels) are the Planck lengths in size. It's computations are similar to those in a spreadsheet (explaining the mystery of entanglement in quantum mechanics), and probability waves (aka psi) can flow through the data, being manifested (aka wavefunction collapse) as particles. Take your pick. -QQuerius
December 10, 2022
December
12
Dec
10
10
2022
11:50 AM
11
11
50
AM
PST
Alan Fox @69,
If Dr. Tour is claiming that OoL is impossible -period- then that’s a reasonable philosophical opinion but not a scientific one. You can’t reject a hypothesis that doesn’t yet exist.
If you actually watched Dr. Tour's videos on the subject, you would know that's NOT what he claims. He claims that we're clueless about the OOL. Where does Dr. Tour claim that it's "impossible"? -QQuerius
December 10, 2022
December
12
Dec
10
10
2022
11:00 AM
11
11
00
AM
PST
Another problem Dr. Tour points out is that in organic synthesis, “nature doesn’t keep a lab notebook.” That means if an abiotic evolutionary step is a failure, nature doesn’t get to go back a step, but rather it must start over from scratch each time.
The lab was the whole prebiotic Earth (or elsewhere if panspermia is evidenced by data from future or current space exploration) and maybe a billion years of trials.Alan Fox
December 10, 2022
December
12
Dec
10
10
2022
01:41 AM
1
01
41
AM
PST
All Dr. Tour was trying to say was that we’re absolutely clueless about how to get from non-organic molecules to organic life.
But nobody is disputing that there is no testable hypothesis for explaining the origin of life on Earth (though there are plenty of ideas and speculations). If Dr. Tour is claiming that OoL is impossible -period- then that's a reasonable philosophical opinion but not a scientific one. You can't reject a hypothesis that doesn't yet exist.Alan Fox
December 10, 2022
December
12
Dec
10
10
2022
01:35 AM
1
01
35
AM
PST
Alan Fox @67,
I watched the zeroth video and was underwhelmed.
Glad you took the time to watch it. All Dr. Tour was trying to say was that we're absolutely clueless about how to get from non-organic molecules to organic life. Dr. Cronin agreed on this point--that we might not know "all the details"--but I'd say that's a GROSS overstatement. We know NONE of the details. In his other videos, Dr. Tour stated that he's not against honest research in OOL. In other words, it's definitely in the domain of science and in the interest of scientists to explore OOL. But Dr. Tour makes the emphatic point that we first have to admit we're clueless before honest research can proceed. Currently, most people think scientists have created life in a test tube, which is false. Researchers perform "series" reactions to produce racemic and contaminated results followed by scalemic and chemically pure concentrations at required temperatures, leaving the purification as an exercise for future generations. This is fundamentally dishonest. It's analogous to medieval alchemists being ever so close to turning lead into gold. https://www.discovermagazine.com/the-sciences/turning-lead-into-gold But current OOL results are more like this amazing demonstration: Experiment | Turning Lead into Gold Lead| Exploratorium https://www.youtube.com/watch?v=5POgg_Zvwc8 Another problem Dr. Tour points out is that in organic synthesis, "nature doesn't keep a lab notebook." That means if an abiotic evolutionary step is a failure, nature doesn't get to go back a step, but rather it must start over from scratch each time. As I've mentioned before, "thermodynamic equilibrium" doesn't come for free. Systems tend to want to crash. My experiments in ecosystem simulation made this frustratingly clear to me. And people concerned about climate change often talk about an irreversible "tipping point" in which our biome crashes. Dr. Cronin also makes the wild speculation that it MUSTA been easy for life to begin on earth because (a) it came into existence quite early in earth's history and (b) . . . Voilà, here we are after all! But this isn't science. AFAIR, Dr. Tour didn't talk about entropy, which as we all know increases in a closed system, but can temporarily reverse in open systems. He also didn't talk about whether the information content in a system can increase. As far as physics is concerned, information is "conserved" and cannot be spontaneously created or destroyed. For example, https://physics.stackexchange.com/questions/606674/how-is-information-conserved-over-time So, for the undisputed concentration of information in DNA, the information had to have come from somewhere else with a higher concentration of information. I think Dr. Cronin's position was that the appearance of life on earth was due simply to "luck." -QQuerius
December 9, 2022
December
12
Dec
9
09
2022
01:16 PM
1
01
16
PM
PST
1 2 3 4

Leave a Reply