Michael J. Behe's Blog, page 36
September 29, 2022
At Sci News: Dogs Can Detect when Humans are Experiencing Stress
Odors emitted by the body constitute chemical signals that have evolved for communication, primarily within species.
A sense of smell of dogs and other canines provides critical information, essential for being aware of potential predators, locating food, identifying conspecifics, and enabling recognition of familial members.
Research on chemical signals has extended to explore inter-specific communication, such as that between mice and humans, cows and humans, horses and humans, and canines and humans.
Image credit: Wilson et al., doi:10.1371/journal.pone.0274143.
Given domestic dogs’ remarkable sense of smell, and their close domestication history with humans, it is possible that they are detecting odors associated with changes within the human body beyond those that have already been established.
The use of dogs to support human psychological conditions such as anxiety, panic attacks and post traumatic stress disorder (PTSD) is growing in popularity, with waiting lists for PTSD service dogs being months-to-years long in some instances.
Such dogs have been reported to improve an individual’s quality of life, social connections, and reduce the number of panic attacks or PTSD symptoms, with the tasks of ‘calming’ and ‘interrupting anxiety’ reported as the most helpful part of their behavioral repertoire.
However, empirical evidence for what mechanisms dogs may be utilizing to respond to their owner’s psychological experience is currently lacking.
“Our findings show that we, as humans, produce different smells through our sweat and breath when we are stressed and dogs can tell this apart from our smell when relaxed — even if it is someone they do not know,” said lead author Clara Wilson, a Ph.D. student in the School of Psychology at Queen’s University Belfast.
Overall, dogs could detect and perform their alert behavior on the sample taken during stress in 675 out of 720 trials, or 93.75% of the time, much greater than expected by chance.
The first time they were exposed to a participant’s stressed and relaxed samples, the dogs correctly alerted to the stress sample 94.44% of the time. Individual dogs ranged in performance from 90% to 96.88% accuracy.
“Dogs can detect an odor associated with the change in volatile organic compounds produced by humans in response to stress, a finding that tells us more about the human-dog relationship and could have applications to the training of anxiety and PTSD service dogs that are currently trained to respond predominantly to visual cues,” the authors said.
“This finding tells us that an acute, negative, psychological stress response alters the odor profile of our breath/sweat, and that dogs are able to detect this change in odor.”
The study was published in the journal PLoS ONE.
Full article at Sci News.
The first sentence of this article includes an (obligatory?) genuflection to the putative powers of “evolution.” As a scientist, it seems unscientific to ascribe an effect as complex as communication/signaling via odor detection and interpretation to evolution, when the naturalistic mechanisms to generate the novel information for such a feat is questionable at best.
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At Evolution News: An Optimistic Solution to the Mystery of Life’s Origin
Walter Bradley and Casey Luskin write:
Image credit: Geralt, via Pixabay.Nobel Prize-winning biologist Jack Szostak: “It is virtually impossible to imagine how a cell’s machines, which are mostly protein-based catalysts called enzymes, could have formed spontaneously as life first arose from non-living matter…Thus, explaining how life began entails a serious paradox.”1Harvard chemist George Whitesides: “Most chemists believe, as do I, that life emerged spontaneously from mixtures of molecules in the prebiotic Earth. How? I have no idea… We need a really good new idea.”2 “I don’t understand how you go from a system that’s random chemicals to something that becomes, in a sense, a Darwinian set of reactions that are getting more complicated spontaneously. I just don’t understand how that works.”3“Origin of Life” entry in the Springer Encyclopedia of Astrobiology by Mexican biologist Antonio Lazcano: “A century and a half after Darwin admitted how little was understood about the origin of life, we still do not know when and how the first living beings appeared on Earth.”4Richard Dawkins, leading evolutionary biologist and New Atheist: “The universe could so easily have remained lifeless and simple…The fact that it did not — the fact that life evolved out of nearly nothing, some 10 billion years after the universe evolved out of literally nothing — is a fact so staggering that I would be mad to attempt words to do it justice.”5Eugene Koonin, a prestigious biologist at the National Center for Biotechnology Information: “The origin of life is one of the hardest problems in all of science, but it is also one of the most important. Origin-of-life research has evolved into a lively, inter-disciplinary field, but other scientists often view it with skepticism and even derision. This attitude is understandable and, in a sense, perhaps justified, given the ‘dirty’ rarely mentioned secret: Despite many interesting results to its credit, when judged by the straightforward criterion of reaching (or even approaching) the ultimate goal, the origin of life field is a failure — we still do not have even a plausible coherent model, let alone a validated scenario, for the emergence of life on Earth. Certainly, this is due not to a lack of experimental and theoretical effort, but to the extraordinary intrinsic difficulty and complexity of the problem. A succession of exceedingly unlikely steps is essential for the origin of life, from the synthesis and accumulation of nucleotides to the origin of translation; through the multiplication of probabilities, these make the final outcome seem almost like a miracle.”6An Alternative SolutionOne might think that, in this series, we have been overly pessimistic in our analysis of the current status of origin-of-life research. But consider what five prestigious origin-of-life thinkers say about the current status of origin-of-life research:
But there is an alternative solution to the information sequence problem and the mystery of life’s origin — and it has the benefit of being based upon our uniform experience with how information arises. I (Walter Bradley) and my coauthors hinted at this solution in the original edition of The Mystery of Life’s Origin, published in 1984, wherein we observed, “We know by experience that intelligent investigators can synthesize proteins and build genes” and concluded that “intelligence is the authentic source of the information in the biological world.”7 In 2020, Discovery Institute published an updated edition of The Mystery of Life’s Origin, and all involved in the project were struck by how few changes were needed, owing to the fact that little meaningful progress had been made in the field of origin-of-life research over the previous 35 years.
NotesAlonso Ricardo and Jack W. Szostak, “Life on Earth,” Scientific American (September 2009), 54-61.George M. Whitesides, “Revolutions in Chemistry: Priestley Medalist George M. Whitesides’ Address,” Chemical and Engineering News 85 (March 26, 2007), 12-17.Conor Myhrvold, “Three Questions for George Whitesides,” MIT Technology Review (September 3, 2012), https://www.technologyreview.com/2012... (accessed November 18, 2020).Antonio Lazcano, “Origin of Life,” Encyclopedia of Astrobiology, eds. M. Gargaud et al. (Berlin, Germany: Springer, 2011), 1184.Richard Dawkins, The Ancestors Tale: A Pilgrimage to the Dawn of Evolution (New York: Houghton Mifflin, 2004), 613.Eugene V. Koonin, The Logic of Chance: The Nature and Origin of Biological Evolution (Upper Saddle River, NJ: FT Press, 2011), 391.Charles B. Thaxton, Walter L. Bradley, and Roger L. Olsen, The Mystery of Life’s Origin: Reassessing Current Theories (Dallas, TX: Lewis and Stanley, 1984), 193, 197.Stephen C. Meyer, “Evidence of Intelligent Design in the Origin of Life,” The Mystery of Life’s Origin: The Continuing Controversy (Seattle, WA: Discovery Institute Press, 2020), 455-456.ID theorists thus propose that the action of an intelligent agent was required for the origin of the first living cell. In keeping with their materialistic outlook, meanwhile, mainstream origin-of-life theorists still maintain, as they must, that a self-replicating cell arose naturally. Darwinian evolution then took things the rest of the way and allowed the grand diversity of living organisms to evolve.
Full article at Evolution News.
It’s fairly evident that non-theistic origin-of-life researchers, while seeing the daunting obstacles to any conceivable naturalistic pathway for abiogenesis, nevertheless believe that life arose naturally, not based on scientific evidence, but due to their nearly absolute determination that God’s creative agency not be considered. What plays a greater role in their convictions, the evidence of nature or their predilections?
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At Evolution News:
Walter Bradley and Casey Luskin write:
Image credit: Geralt, via Pixabay.Nobel Prize-winning biologist Jack Szostak: “It is virtually impossible to imagine how a cell’s machines, which are mostly protein-based catalysts called enzymes, could have formed spontaneously as life first arose from non-living matter…Thus, explaining how life began entails a serious paradox.”1Harvard chemist George Whitesides: “Most chemists believe, as do I, that life emerged spontaneously from mixtures of molecules in the prebiotic Earth. How? I have no idea… We need a really good new idea.”2 “I don’t understand how you go from a system that’s random chemicals to something that becomes, in a sense, a Darwinian set of reactions that are getting more complicated spontaneously. I just don’t understand how that works.”3“Origin of Life” entry in the Springer Encyclopedia of Astrobiology by Mexican biologist Antonio Lazcano: “A century and a half after Darwin admitted how little was understood about the origin of life, we still do not know when and how the first living beings appeared on Earth.”4Richard Dawkins, leading evolutionary biologist and New Atheist: “The universe could so easily have remained lifeless and simple…The fact that it did not — the fact that life evolved out of nearly nothing, some 10 billion years after the universe evolved out of literally nothing — is a fact so staggering that I would be mad to attempt words to do it justice.”5Eugene Koonin, a prestigious biologist at the National Center for Biotechnology Information: “The origin of life is one of the hardest problems in all of science, but it is also one of the most important. Origin-of-life research has evolved into a lively, inter-disciplinary field, but other scientists often view it with skepticism and even derision. This attitude is understandable and, in a sense, perhaps justified, given the ‘dirty’ rarely mentioned secret: Despite many interesting results to its credit, when judged by the straightforward criterion of reaching (or even approaching) the ultimate goal, the origin of life field is a failure — we still do not have even a plausible coherent model, let alone a validated scenario, for the emergence of life on Earth. Certainly, this is due not to a lack of experimental and theoretical effort, but to the extraordinary intrinsic difficulty and complexity of the problem. A succession of exceedingly unlikely steps is essential for the origin of life, from the synthesis and accumulation of nucleotides to the origin of translation; through the multiplication of probabilities, these make the final outcome seem almost like a miracle.”6An Alternative SolutionOne might think that, in this series, we have been overly pessimistic in our analysis of the current status of origin-of-life research. But consider what five prestigious origin-of-life thinkers say about the current status of origin-of-life research:
But there is an alternative solution to the information sequence problem and the mystery of life’s origin — and it has the benefit of being based upon our uniform experience with how information arises. I (Walter Bradley) and my coauthors hinted at this solution in the original edition of The Mystery of Life’s Origin, published in 1984, wherein we observed, “We know by experience that intelligent investigators can synthesize proteins and build genes” and concluded that “intelligence is the authentic source of the information in the biological world.”7 In 2020, Discovery Institute published an updated edition of The Mystery of Life’s Origin, and all involved in the project were struck by how few changes were needed, owing to the fact that little meaningful progress had been made in the field of origin-of-life research over the previous 35 years.
NotesAlonso Ricardo and Jack W. Szostak, “Life on Earth,” Scientific American (September 2009), 54-61.George M. Whitesides, “Revolutions in Chemistry: Priestley Medalist George M. Whitesides’ Address,” Chemical and Engineering News 85 (March 26, 2007), 12-17.Conor Myhrvold, “Three Questions for George Whitesides,” MIT Technology Review (September 3, 2012), https://www.technologyreview.com/2012... (accessed November 18, 2020).Antonio Lazcano, “Origin of Life,” Encyclopedia of Astrobiology, eds. M. Gargaud et al. (Berlin, Germany: Springer, 2011), 1184.Richard Dawkins, The Ancestors Tale: A Pilgrimage to the Dawn of Evolution (New York: Houghton Mifflin, 2004), 613.Eugene V. Koonin, The Logic of Chance: The Nature and Origin of Biological Evolution (Upper Saddle River, NJ: FT Press, 2011), 391.Charles B. Thaxton, Walter L. Bradley, and Roger L. Olsen, The Mystery of Life’s Origin: Reassessing Current Theories (Dallas, TX: Lewis and Stanley, 1984), 193, 197.Stephen C. Meyer, “Evidence of Intelligent Design in the Origin of Life,” The Mystery of Life’s Origin: The Continuing Controversy (Seattle, WA: Discovery Institute Press, 2020), 455-456.ID theorists thus propose that the action of an intelligent agent was required for the origin of the first living cell. In keeping with their materialistic outlook, meanwhile, mainstream origin-of-life theorists still maintain, as they must, that a self-replicating cell arose naturally. Darwinian evolution then took things the rest of the way and allowed the grand diversity of living organisms to evolve.
Full article at Evolution News.
It’s fairly evident that non-theistic origin-of-life researchers, while seeing the daunting obstacles to any conceivable naturalistic pathway for abiogenesis, nevertheless believe that life arose naturally, not based on scientific evidence, but due to their nearly absolute determination that God’s creative agency not be considered. What plays a greater role in their convictions, the evidence of nature or their predilections?
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September 28, 2022
Live Radar feed on Hurricane Ian as it tracks across Florida
Here:
We need to recognise that Atlantic Hurricanes have a Season June to November, and that in the Pacific, they are a year-round phenomenon. END
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At Science Daily: Why whales don’t get brain damage when they swim
There are many theories as to the exact use of these networks of blood vessels cradling a whale’s brain and spine, known as ‘retia mirabilia’, or ‘wonderful net’, but now UBC zoologists believe they’ve solved the mystery, with computer modeling backing their predictions.
Credit: Todd Cravens
Land mammals such as horses experience ‘pulses’ in their blood when galloping, where blood pressures inside the body go up and down on every stride. In a new study, lead author Dr. Margo Lillie and her team have suggested for the first time that the same phenomenon occurs in marine mammals that swim with dorso-ventral movements; in other words, whales. And, they may have found out just why whales avoid long-term damage to the brain for this.
In all mammals, average blood pressure is higher in arteries, or the blood exiting the heart, than in veins. This difference in pressure drives the blood flow in the body, including through the brain, says Dr. Lillie, a research associate emerita in the UBC department of zoology. However, locomotion can forcefully move blood, causing spikes in pressure, or ‘pulses’ to the brain. The difference in pressure between the blood entering and exiting the brain for these pulses can cause damage.
Long-term damage of this kind can lead to dementia in human beings, says Dr. Lillie. But while horses deal with the pulses by breathing in and out, whales hold their breath when diving and swimming. “So if cetaceans can’t use their respiratory system to moderate pressure pulses, they must have found another way to deal with the problem,” says Dr. Lillie.
Dr. Lillie and colleagues theorized that the retia use a ‘pulse-transfer’ mechanism to ensure there is no difference in blood pressure in the cetacean’s brain during movement, on top of the average difference. Essentially, rather than dampening the pulses that occur in the blood, the retia transfer the pulse in the arterial blood entering the brain to the venous blood exiting, keeping the same ‘amplitude’ or strength of pulse, and so, avoiding any difference in pressure in the brain itself.
The researchers collected biomechanic parameters from 11 cetacean species, including, fluking frequency, and input these data into a computer model.
“Our hypothesis that swimming generates internal pressure pulses is new, and our model supports our prediction that locomotion-generated pressure pulses can be synchronized by a pulse transfer mechanism that reduces the pulsatility of resulting flow by up to 97 per cent,”says senior author Dr. Robert Shadwick, professor emeritus in the UBC department of zoology.
The model could potentially be used to ask questions about other animals and what’s happening with their blood pressure pulses when they move, including humans, says Dr. Shadwick. And while the researchers say the hypothesis still needs to be tested directly by measuring blood pressures and flow in the brain of swimming cetaceans, this is currently not ethically and technically possible, as it would involve putting a probe in a live whale.
“As interesting as they are, they’re essentially inaccessible,” he says. “They are the biggest animals on the planet, possibly ever, and understanding how they manage to survive and live and do what they do is a fascinating piece of basic biology.”
“Understanding how the thorax responds to water pressures at depth and how lungs influence vascular pressures would be an important next step,” says co-author Dr. Wayne Vogl, professor in the UBC department of cellular and physiological sciences. “Of course, direct measurements of blood pressure and flow in the brain would be invaluable, but not technically possible at this time.”
Science Daily
The mechanism that protects a whale’s brain from potentially harmful blood pressure pulses while swimming, ‘retia mirabilia,” could be translated, “miraculous net”. It’s certainly “wonderful” in its unique benefit to whales, but its origin and integration into the whale’s physical being is an example of something consistent with a miraculous instance of intelligent design.
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At Medical Xpress: Breaks in ‘junk’ DNA give scientists new insight into neurological disorders
The research from the University of Sheffield’s Neuroscience Institute and Healthy Lifespan Institute gives important new insights into so-called junk DNA and how it impacts on neurological disorders such as Motor Neuron Disease (MND) and Alzheimer’s.
Until now, the repair of junk DNA, which makes up 98% of DNA, has been largely overlooked by scientists, but the new study published in Nature found it is much more vulnerable to breaks from oxidative genomic damage than previously thought. This has vital implications on the development of neurological disorders.
The researchers also identified the pathway of how oxidative breaks are formed and repaired. Repairing these breaks in junk DNA is essential for producing proteins that protect us from disease.
Oxidative stress is an unavoidable consequence of cellular metabolism and can be influenced by factors such as diet, lifestyle and environment. In the long term, oxidative stress can cause damage to the body’s cells, proteins and DNA, accelerating the aging process and contributing to the development of neurological diseases such as dementia.
It is hoped this study could pave the way for further research that may potentially help speed up the detection of biomarkers of disease, and allow for earlier intervention to help prevent the onset or progression of neurological disorders such as Alzheimer’s and MND in those who have the relevant gene.
Copyright © 2022 Uncommon Descent . This Feed is for personal non-commercial use only. If you are not reading this material in your news aggregator, the site you are looking at is guilty of copyright infringement UNLESS EXPLICIT PERMISSION OTHERWISE HAS BEEN GIVEN. Please contact legal@uncommondescent.com so we can take legal action immediately.“Until now the repair of what people thought is junk DNA has been mostly overlooked, but our study has shown it may have vital implications on the onset and progression of neurological disease.
“The research also shows that it could have implications for making cancer treatments more effective.”
Full article at Medical Xpress.
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September 27, 2022
At Evolution News: Theoretical Physicist Sabine Hossenfelder on the Deficiency of Alternative Models to Big Bang Cosmology
Physicist Brian Miller writes:
Theoretical physicist Sabine Hossenfelder recently posted a very informative video asking “Did the Big Bang happen?” She explains why alternative theories to the Big Bang model fail to better explain the cosmological data. She also unintentionally affirms the fine-tuning argument for design in the universe.
Image credit: Rick Bolin, via Flickr (cropped)Success of the Big Bang Theory
Hossenfelder begins by summarizing the evidence for Big Bang cosmology based on Einstein’s theory of relativity and the observed expansion of space. She also explains why the exact details of the early universe remain a mystery. Cosmologists have a limited understanding of the physics of this time when the energy of particles exceeded what the Large Hadron Collider at CERN could generate. In addition, elucidating the dynamics of the universe’s earliest epoch requires a theory of quantum gravity, which does not currently exist.
Even given these limitations, the Big Bang theory represents the best model since it is founded on general relativity, and Einstein’s theory is supported by numerous pieces of observational evidence such as the bending of light around stars. In addition, the standard model (i.e., Big Bang model with a cosmological constant and cold dark matter) predicts many observations such as the Cosmic Microwave Background and the galactic filaments using simple initial conditions. The universe’s initial state is assumed to approximate a uniform distribution of mass-energy.
Deficiency of Other ModelsThe standard model thus provides a “simple” explanation for the current state of the universe since it requires few variables. These include the variables in the relatively simple equations for the expansion of the universe, the initial mass-energy density, and the initial expansion rate.
Hossenfelder then provides a deeply insightful exposition on the inferiority of other models. All other models rely on different equations for the dynamics of the early universe. But these equations can only generate our current state by choosing far more complex initial conditions:
…Einstein’s equations together with their initial values in the early universe provide a simple explanation for the observations we make today. When I say simple, I mean simple in a quantitative way you need few numbers to specify. If you used a different equation, then the initial state would be more difficult. You’d need to put in more numbers. And the theory wouldn’t explain as much.
The key problem is that nearly any set of equations could yield the current state of the universe with the right choice of initial conditions. But neither the theory’s underlying equations nor the initial conditions can be independently verified. And the alternative theories provide no additional knowledge. Hossenfelder summarizes as follows:
The God HypothesisAnd then they also need a different initial state, so you might no longer find a Big Bang. As I said earlier, you can always do this, because for any evolution law there will be some initial state that will give you the right prediction for today. The problem is that this makes a simple explanation more complicated, so these theories are not scientifically justifiable. They don’t improve the explanatory power of the standard cosmological model. Another way to put it is that all those complicated ideas for how the universe began are unnecessary to explain what we observe.
Hossenfelder lists several theories that fall under her critique including Penrose’s cyclic cosmology, the ekpyrotic universe that postulates colliding membranes, and the no-boundary proposal by Jim Hartle and Stephen Hawking. Stephen Meyer also critiqued these theories in his book Return of the God Hypothesis. But Meyer came to starkly different conclusions.
Hossenfelder concludes that “we are facing the limits of science itself.” And the question of the universe’s origin “we’ll never be able to answer.” In contrast, Meyer argues that the evidence for a beginning and the required fine tuning of the universe to support life point to a mind behind our world. The fact that all alternative cosmological theories require highly specific initial conditions to explain our present life-friendly universe only reinforces the fine-tuning argument and by extension the God Hypothesis.
Evolution News
The conclusion, “we are facing the limits of science itself,” is supportive of the thesis derived from scientific evidence presented in my book, Canceled Science, the idea that there are “boundaries of science”. We observe phenomena in this universe that are beyond the known constraints imposed by the laws of nature, implying that natural explanations are insufficient to explain their existence. The origin of this universe is one of those observed realities that transcend the abilities of nature. But it’s not the only one. The knife-edge fine-tuning of the laws and parameters of physics to support life, the origin of life on Earth, the multiplicity of finely-tuned conditions on Earth that allow millions of species to thrive, the origin of consciousness, the human mind, our sense of morality, and others all point beyond nature to a transcendent origin – what Meyer calls the God Hypothesis.
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September 26, 2022
At Universe Today: Life can Thrive Around Even the Smallest Stars
BRIAN KOBERLEIN writes:
Photosynthesis is probably the most important chemical reaction for life on Earth. It is the process plants use to transform sunlight into energy it can use. Through it, plants can produce carbohydrates they can use (and we can eat when we harvest plants), generating oxygen as a by-product. Photosynthesis is why Earth’s atmosphere is about 20% oxygen. No photosynthesis, no life on Earth as we know it.
It’s also the reason so many plants are green. Most plants use chlorophyll as part of the photosynthesis process, which reflects green light while absorbing red and blue light through photosynthesis. If you think about it, that’s a bit odd, since the Sun gives off its most intense light in the green range of the spectrum. There is actually a photosynthesis chemical known as retinal which absorbs green and reflects red and blue. If plants used retinal instead of chlorophyll, then most plants would be purple. Some bacteria use retinal, but it turns out for sunlight that chlorophyll is more efficient, so overall it gives more bang for your buck. It’s possible that early life used retinal, which is a simpler molecule, before figuring out how to use chlorophyll.
Habitable zone comparison: Sun vs. red dwarf. Credit: T Roger/Europlanet 2024 RI.Of course, photosynthesis evolved to take advantage of a bright yellow star that emits most of its light in the visible spectrum. But Sun-like stars make up less than 8% of main sequence stars in our galaxy. Red dwarfs, on the other hand, make up 75% of main sequence stars. Statistically, the vast majority of potentially habitable planets orbit a red dwarf. And red dwarfs are much smaller and cooler than our Sun. Most of the light they emit is in the infrared. Infrared light is nice and warm, but does it have the kick you need to power photosynthesis? In a recent study, a research team tried to find out.
To do this they created a starlight simulator. It’s an array of LEDs set up to mimic the spectrum of a red dwarf. The device can mimic the spectra of various types of stars, but since red dwarfs are so common they studied that first. They then created an atmosphere that might be typical for an early habitable world, tossed in some bacteria, and illuminated it with simulated starlight.
They started with cyanobacteria, which were among the first type of organisms on Earth to use photosynthesis to produce oxygen. They are particularly good at surviving in harsh environments. The cyanobacteria thrived and grew under the infrared glow of a red dwarf, so the team repeated the experiment with red and green algae. Both of them thrived as well. So even though red dwarfs don’t emit the type of light which drove the evolution of photosynthesis, terrestrial organisms could live under a red dwarf sun. This is great news for everyone wanting to find extraterrestrial life.
Of course, there are other challenges with red dwarfs that might rule out life on their worlds. The stars are known to emit powerful flares that might strip the atmospheres of close worlds, and they might not have the elemental resources necessary for complex organisms. But it is a great study that has shined a little light on our understanding of life on other planets.*
Note: Red dwarf stars have their habitable zone too close for orbiting planets to avoid being gravitationally locked so that their day (rotational period) becomes similar to their year (orbital period). This means that the planets disparate temperature zones would become highly unfavorable to life, especially any sort of advanced life.
*Also, “our understanding of life on other planets” should include the realization that no evidence has ever been observed for life on other planets, and that decades of origin-of-life research has only reinforced the conclusion that natural processes seem entirely insufficient to produce life of any kind, here or elsewhere.
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At Evolution News: Origin of the First Self-Replicating Molecules
Walter Bradley and Casey Luskin write:
In an undergraduate seminar taught by Stanley Miller that I (Casey Luskin) took as a student at the University of California, San Diego, Dr. Miller taught us that “making compounds and making life are two different things.”1 Many variants of Stanley Miller’s experimental setup have been used in attempting to demonstrate the conversion of energy-rich, gaseous-phase chemicals into amino acids and other biomolecular monomers. But this is not nearly sufficient to generate life. Any origin-of-life explanation must include plausible biochemical paths from individual bio-building blocks like amino acids or nucleic acids to functional polymers such as proteins and DNA. The origin-of-life explanation must also include ways to speed up chemical reactions that are naturally slow. In living cells, long chains of amino acids fold up into 3-D structures that allow them to function as enzymes that greatly accelerate chemical reactions.
Image: RNA, via Illustra Media’s documentary Origin.The Most Popular ProposalMore importantly, any origin-of-life model must account for the very particular sequencing of the molecules — i.e., the ordering of amino acids in proteins and nucleotide bases in RNA and DNA that allows them to function properly. This means explaining a crucial aspect of life: the origin of its information, or what proponents of intelligent design (ID) call the “information sequence problem.”
For some theorists, the origin of life is defined as the natural origin of a self-replicating system capable of undergoing Darwinian evolution.2 The most popular proposal for the first self-replicating molecule is RNA — where life was first based upon RNA carrying both genetic information (akin to modern DNA) and performing catalytic functions (akin to modern enyzmes), in what is termed the RNA world. Before we delve deeply into that, it is instructive to use the proceedings of a conference organized by the International Society for the Study of the Origin of Life (ISSOL) at the University of California, Berkeley, in 1986 to measure the progress that has been made in origin-of-life research from 1952-1986.
I (Walter Bradley) attended this conference and watched one of the plenary sessions devoted to a spirited debate between scientists who believed that the first life was made of DNA (“DNA-first”) and those who believed that the first biomolecules were proteins (“protein-first”). Neither group had yet been able to synthesize under plausible conditions either protein or DNA. Proteins can act as a chemical catalyst. DNA is the repository of information that is used to make functional protein. One of the outcomes from the conference was the sense that neither protein-first nor DNA-first were promising pathways to explaining the origin of life.
Five Huge BarriersAt the concluding plenary session, leading origin-of-life researcher Robert Shapiro addressed the RNA world and traced citations in the biochemical literature of the synthesis of RNA molecules under conditions thought to represent the early Earth conditions. The results were shocking. He cited a 1986 paper indicating RNA synthesis under prebiotic conditions had been demonstrated repeatedly, citing a 1985 paper and alluding to others. But that 1985 paper did not present original work — rather, it cited a 1984 paper and went all the way back to 1968 without any original work cited. A close reading of the 1968 paper indicated that the authors thought that they might have synthesized RNA molecules under prebiotic conditions but had not actually found any.
Shapiro’s talk subsequently presented five huge barriers to this biochemical pathway from prebiotic chemistry to the first living systems. At the end of his dramatic presentation, the room of most of the world’s most active origin-of-life researchers fell silent. The chair of the session, who was also the editor of the premiere journal Origins of Life and Evolution of Biospheres, repeatedly invited questions from the stunned audience. It was the only time in my (Walter Bradley) professional lifetime that I attended a plenary session of scientists and engineers where there were no questions. The chair closed the session without any questions offered, and he closed with the comment, “Robert, do you have to be so pessimistic?” Robert did not reply, but might have said he was letting the data do the talking, and the data told a very pessimistic story.
History has confirmed Shapiro’s pessimism. Despite these difficulties, to this day, the RNA world remains the most popular model for the origin of life. But there are major problems with the RNA world hypothesis and claims that a self-replicating RNA molecule appeared by pure chance.
A Second ProblemFirst, RNA has not been shown to assemble in a laboratory without the help of a skilled chemist intelligently guiding the process. Origin-of-life theorist Steven Benner explained that a major obstacle to the natural production of RNA is that “RNA requires water to function, but RNA cannot emerge in water, and does not persist in water without repair” due to water’s “rapid and irreversible” corrosive effects upon RNA.3 In this “water paradox,” Benner explains that “life seems to need a substance (water) that is inherently toxic to polymers (e.g., RNA) necessary for life.”4
The Origin of InformationToday, RNA is capable of carrying genetic information, but RNA world advocates claim that in the past, it also fulfilled the kinds of catalytic roles that enzymes perform today. A second problem with the RNA world is that RNA molecules do not exhibit many of the properties that allow proteins to serve as worker molecules in the cell. While RNA has been shown to perform a few roles, there is no evidence that it could perform all necessary cellular functions.8 As one paper put it, proteins are “one million times fitter than RNA as catalysts” and “[t]he catalytic repertoire of RNA is too limited.”9
The most fundamental problem with the RNA world hypothesis is its inability to explain the origin of information in the first self-replicating RNA molecule — which experts suggest would have had to be at least 100 nucleotides long, if not between 200 and 300 nucleotides in length.10 How did the nucleotide bases in RNA become properly ordered to produce life? There are no known chemical or physical laws that can do this. To explain the ordering of nucleotides in the first self-replicating RNA molecule, origin-of-life theorists have no explanation other than blind chance. As noted, ID theorists call this obstacle the information sequence problem, but multiple mainstream theorists have also observed the great unlikelihood of naturally producing a precise RNA sequence required for replication.
Elsewhere, Shapiro notes, “The sudden appearance of a large self-copying molecule such as RNA was exceedingly improbable” with a probability that “is so vanishingly small that its happening even once anywhere in the visible universe would count as a piece of exceptional good luck.”12 A 2020 paper in Scientific Reports similarly notes, “Abiotic emergence of ordered information stored in the form of RNA is an important unresolved problem concerning the origin of life” because “the formation of such a long polymer having a correct nucleotide sequence by random reactions seems statistically unlikely.”13
An Intractable ProblemThis suggest a grave theoretical difficulty where RNA world theorists are faced with a “chemical theory that makes destruction, not biology, the natural outcome.”15
The paper in Scientific Reports proposed a solution to these quandaries that showed just how intractable this problem is: It concluded that because the formation of a single self-replicating RNA molecule is prohibitively unlikely in the observable universe, and therefore the universe must be far larger than we observe — an “inflationary universe” that increases the probabilistic resources until such an unlikely event becomes likely. This is just like the materialist response to the fine-tuning of physics: When the observed specificity of nature appears to indicate design, they invent multiverses to overcome probabilistic difficulties. When RNA world theorists are appealing to the origin-of-life’s version of the multiverse to avoid falsification, it’s clear that their project has fatal problems.
Notes
Statements made by Stanley Miller at a talk given by him for a UCSD Origins of Life seminar class on January 19, 1999 (the talk was attended and notated by the author of this article).Steven A. Benner, “Paradoxes in the Origin of Life,” Origins of Life and Evolution of Biospheres 44 (2014), 339-343.Benner, “Paradoxes in the Origin of Life.”Benner, “Paradoxes in the Origin of Life.”Robert Shapiro, quoted in Richard Van Noorden, “RNA world easier to make,” Nature News (May 13, 2009), http://www.nature.com/news/2009/09051... (accessed November 18, 2020).James Tour, “Are Present Proposals on Chemical Evolutionary Mechanisms Accurately Pointing Toward First Life?,” Theistic Evolution: A Scientific, Philosophical, and Theological Critique, eds. Edited by J.P. Moreland, Stephen C. Meyer, Christopher Shaw, Ann K. Gauger, and Wayne Grudem (Wheaton, IL: Crossway, 2017), 165-191.Michael P. Robertson and Gerald F. Joyce, “The Origins of the RNA World,” Cold Spring Harbor Perspectives in Biology 4 (May 2012), a003608.See Stephen C. Meyer, Signature in the Cell: DNA and the Evidence for Intelligent Design (New York: HarperOne, 2009), 304.Harold S Bernhardt, “The RNA world hypothesis: the worst theory of the early evolution of life (except for all the others),” Biology Direct 7 (2012), 23.Jack W. Szostak, David P. Bartel, and P. Luigi Luisi, “Synthesizing Life,” Nature, 409 (January 18, 2001), 387-390; Tomonori Totani, “Emergence of life in an inflationary universe,” Scientific Reports 10 (2020), 1671.Robert Shapiro, “A Replicator Was Not Involved in the Origin of Life,” IUBMB Life 49 (2000), 173-176.Robert Shapiro, “A Simpler Origin for Life,” Scientific American (June 2007), 46-53.Totani, “Emergence of life in an inflationary universe.”Benner, “Paradoxes in the Origin of Life.”Benner, “Paradoxes in the Origin of Life.”Full article at Evolution News.
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September 24, 2022
From IAI News: How infinity threatens cosmology
Peter Cameron, Emeritus Professor Mathematics at Queen Mary, University of London, writes:
There are many approaches to infinity through the twin pillars of science and religion, but I will just restrict my attention here to the views of mathematicians and physicists.
IAI NewsAristotle was one of the most influential Greek philosophers. He believed that we could consider “potential infinity” (we can count objects without knowing how many more are coming) but that a “completed infinity” is taboo. For mathematicians, infinity was off-limits for two millennia after Aristotle’s ban. Galileo tried to tackle the problem, noting that an infinite set could be matched up with a part of itself, but in the end drew back. It was left to Cantor in the nineteenth century to show us the way to think about infinity, which is accepted by most mathematicians now. There are infinitely many counting numbers; any number you write down is a negligible step along the way to infinity. So Cantor’s idea was to imagine we have a package containing all these numbers; put a label on it saying “The natural numbers”, and treat the package as a single entity. If you want to study individual numbers, you can break open the package and take them out to look at them. Now you can take any collection of these packages, and bundle them up to form another single entity. Thus, set theory is born. Cantor investigated ways of measuring these sets, and today set theory is the commonest foundation for mathematics, though other foundations have been proposed.
One of Cantor’s discoveries is that there is no largest infinite set: given any set you can always find a larger one. The smallest infinite set is the set of natural numbers. What comes next is a puzzle which can’t be resolved at present. It may be the real (decimal) numbers, or maybe not. Our current foundations are not strong enough, and building larger telescopes will not help with this question. Perhaps in the future we will adopt new foundations for mathematics which will resolve the question.
These questions keep set theorists awake at night; but most mathematicians work near the bottom of this dizzying hierarchy, with small infinities. For example, Euclid proved that the prime numbers “go on for ever”. (Aristotle would say, “Whatever prime you find, I can find a larger one.”
While Kronecker (a fierce opponent of Cantor’s ideas) thought in the nineteenth century that “God created the natural numbers; the rest is the work of man”, we can now build the natural numbers using the tools of set theory, starting from nothing (more precisely the empty set).
Mathematicians know, however, that there is a huge gap between the finite and the infinite. If you toss a coin 100 times, it is not impossible (just very unlikely) that it will come down tails each time. But, if you could imagine tossing a coin infinitely often, then the chance of not getting heads and tails equally often is zero. Of course, you could never actually perform this experiment; but mathematics is a conceptual science, and we are happy to accept this statement on the basis of a rigorous proof.
Infinity in physics and cosmology has not been resolved so satisfactorily. The two great twentieth-century theories of physics, general relativity (the theory of the very large) and quantum mechanics (the theory of the very small) have resisted attempts to unite them. The one thing most physicists can agree on is that the universe came into being a finite time ago (about 13.7 billion years) — large, but not infinite.
The James Webb Space Telescope has just begun showing us unprecedented details in the universe. As well as nearby objects, it sees the furthest objects ever observed. Because light travels at a finite speed, these are also the oldest objects observed, having been formed close to the beginning of the Universe. The finite speed of light also puts limits on what we can see; if an object is so far away that its light could not reach us if it travelled for the whole age of the universe, then we are unaware of its existence. So Malunkyaputta’s question about whether the universe is finite or infinite is moot. But is it eternal or not? That is a real question, and is so far undecided.
Attempts to reconcile relativity and quantum theory have been made. The ones currently most promising adopt a very radical attitude to infinity. They deny that the infinitely small can exist in the universe, but prescribe a minimum possible scale, essentially the so-called Planck scale.
Such a solution would put an end to Zeno’s paradox. Zeno denied the possibility of motion, since to move from A to B you first have to move to a point C halfway to B, and before that to a point D halfway from A to C, and so on to infinity. If space is not infinitely divisible, then this infinite regress cannot occur. (This solution was already grasped by Democritus and the early Greek atomists.)
Of course, this leaves us with a conceptual problem similar to the one raised by the possibility that the university is finite. In that case, the obvious question is “If the universe has an edge, what is beyond it?” In the case of the Planck length, the question would be “Given any length, however small, why can’t I just take half of it?”
Perhaps because we have been conditioned by Zeno’s paradox, we tend to think of the points on a line to be, like the real numbers, infinitely divisible: between any two we can find another. But current thinking is that the universe is not built this way.
More important to physics, the atomist hypothesis also gets rid of another annoying occurrence of infinity in physics. Black holes in general relativity are points of spacetime where the density of matter becomes infinite and the laws of physics break down. These have been a thorn in the flesh of cosmologists since their existence was first predicted, since by definition we cannot understand what happens there. If space is discrete, we cannot put infinitely many things infinitely close together, and the paradox is avoided. We can still have extremely high density; the black hole recently observed and photographed at the centre of our own galaxy is (on this theory) just a point of such high density that light cannot escape, but does not defy our ability to understand it.
Time, however, remains a problem; current theories cannot decide the ultimate fate of the universe. Does it end with heat death, a cold dark universe where nothing happens? Does the mysterious “dark energy” become so strong that it rips the universe to shreds? Or does the expansion from the Big Bang go into reverse, so that the universe ends in a Big Crunch?
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None of this matters to us individually. The sun will expand and swallow the earth long before the universe reaches its end.
Full article at IAI News.
Although this article glosses over some concepts in physics and cosmology, it raises interesting points to ponder.
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