Michael J. Behe's Blog, page 33

At Science Daily: Study finds unexpected protective properties of pain

Work in mice illuminates how pain neurons shield the gut from damage.

Pain has been long recognized as one of evolution’s most reliable tools to detect the presence of harm and signal that something is wrong — an alert system that tells us to pause and pay attention to our bodies.

Pain signals us that something’s wrong. Here, we also raise a signal that something’s wrong when evolution is given credit for a complex biochemical, systemic sensory and feedback process, without any research showing how unguided natural processes could accomplish such a task.

But what if pain is more than just a mere alarm bell? What if pain is in itself a form of protection?

A new study led by researchers at Harvard Medical School suggests that may well be the case in mice.

The research, published Oct. 14 in Cell, shows that pain neurons in the mouse gut regulate the presence of protective mucus under normal conditions and stimulate intestinal cells to release more mucus during states of inflammation.

The work details the steps of a complex signaling cascade, showing that pain neurons engage in direct crosstalk with mucus-containing gut cells, known as goblet cells.

“It turns out that pain may protect us in more direct ways than its classic job to detect potential harm and dispatch signals to the brain. Our work shows how pain-mediating nerves in the gut talk to nearby epithelial cells that line the intestines,” said study senior investigator Isaac Chiu, associate professor of immunobiology in the Blavatnik Institute at HMS. “This means that the nervous system has a major role in the gut beyond just giving us an unpleasant sensation and that it’s a key player in gut barrier maintenance and a protective mechanism during inflammation.”

Complete article at Science Daily.

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L&FP, 62a: Science can rightly — and usefully — be viewed as “reverse engineering of the natural world”

Here, it is helpful to headline an update to L&FP, 62, as we need to return to a rich vein of thought that allows us to approach science in light of systems engineering perspectives:

[[We may add a chart on a key subset of SE, reverse engineering, RE:

A summary of RE, HT: Global Spec (We may often start with step 2, and obviously Step 1 has a typo for purpose, a little RE exercise in itself.)

One of the most significant Reverse Engineering-Forward Engineering exercises was the clean room duplication of the IBM PC’s operating framework that allowed lawsuit-proof clones to be built that then led to the explosion of PC-compatible machines. By the time this was over, IBM sold out to Lenovo and went back to its core competency, Mainframes. Where, now, a mainframe today is in effect a high end packaged server farm; the microprocessor now rules the world, including the supercomputer space.

Here, let us add, a Wikipedia confession as yet another admission against interest:

Reverse engineering (also known as backwards engineering or back engineering) is a process or method through which one attempts to understand through deductive reasoning [–> actually, a poor phrase for inference to best explanation, i.e. abductive reasoning] how a previously made device, process, system, or piece of software accomplishes a task with very little (if any) [–> initial] insight into exactly how it does so. It is essentially the process of opening up or dissecting [–> telling metaphor] a system [–> so, SE applies] to see how it works, in order to duplicate or enhance it. Depending on the system under consideration and the technologies employed, the knowledge gained during reverse engineering can help with repurposing obsolete objects, doing security analysis, or learning how something works.[1][2]

Although the process is specific to the object on which it is being performed, all reverse engineering processes consist of three basic steps: Information extraction, Modeling, and Review. Information extraction refers to the practice of gathering all relevant information [–> telling word, identify the FSCO/I present in the entity, and of course TRIZ is highly relevant esp its library of key design strategies] for performing the operation. Modeling refers to the practice of combining the gathered information into an abstract model [–> that is, the inferred best explanation], which can be used as a guide for designing the new object or system. [–> guess why I think within this century we should be able to build a cell de novo?] Review refers to the testing of the model to ensure the validity of the chosen abstract.[1] Reverse engineering is applicable in the fields of computer engineering, mechanical engineering, design, electronic engineering, software engineering, chemical engineering,[3] and systems biology.[4] [More serious discussion, here.]

We can see that

one paradigm for science is, reverse engineering nature.

This directly connects to, technology as using insights from RE of nature to forward engineer [FE] our own useful systems. And of course that takes us to a theme of founders of modern science, that they were “thinking God’s thoughts after him.”]]

This approach is obviously design friendly and reflects commonplace views of many founders of modern science. For example, Johannes Kepler is commonly said to have written:

“I was merely thinking God’s thoughts after him. Since we astronomers are priests of the highest God in regard to the book of nature, it benefits us to be thoughtful, not of the glory of our minds, but rather, above all else, of the glory of God.”

Even were this apocryphal, it would be accurate to the views of many scientists then and now. However, the reverse engineering view is not merely of historical or philosophy of science interest. For, thanks to the works of such pioneers, we have a rich body of results that gives us confidence that such an approach builds on the framework of rational principles that have unfolded as we noted patterns in nature, inferred laws of nature and built explanatory models aka theories.

For telling instance, observe the ribosome in protein synthesis, showing a direct comparison to the role of punch paper tape and magnetic tape in the older generation of computers:

Such shows machine language in action. As Wikipedia confesses:

In computer programming, machine code is any low-level programming language, consisting of machine language instructions, which are used to control a computer’s central processing unit (CPU). Each instruction causes the CPU to perform a very specific task, such as a load, a store, a jump, or an arithmetic logic unit (ALU) operation on one or more units of data in the CPU’s registers or memory. Machine code is a strictly numerical language which is designed to run as fast as possible, and may be considered as the lowest-level representation of a compiled or assembled computer program or as a primitive and hardware-dependent programming language.

This is directly parallel — not merely, dismissibly loosely analogous to — the function of mRNA in the ribosome. Once threaded and aligned, we have AUG, START (and load Methionine), EXTEND (and load another specified AA), EXTEND . . . STOP. This is algorithmic procedure, and the code is based on a four state, prong height element similar to a Yale type, pin tumbler lock. But of course, using molecular nanotech with CG and AT or AU as complementary pairs:

This approach points onward to Wigner’s wondering about the uncanny effectiveness of mathematics in sciences. To this, my answer has been [see popular article here], that the logic of structure and quantity for possible worlds puts a core of Math into the structure of any feasible world. It only remains for us to explore and reverse engineer that structure then elaborate our own onward synthesis of bodies of knowledge.

Yes, Mathematics can also in key part be approached on reverse engineering, it’s not just Science here, indeed even logic as a technical discipline fits in. END

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At Reasons.org: Exploring the Mystical Connection between Math, Mind, and Nature

Dr. Otis Graf writes:

When scientists experience “mystical moments,” such breakthroughs usually occur when a scientist discovers something remarkable about the physical world. However, some scientists attest to a different kind of mystical (aha) moment that involves the natural, elegant interplay among the human mind, mathematics, computation, and complex instruments. How do we account for this mystical connection? Can naturalism explain it, or is it more consistent with Christianity?  

One Scientist’s Mystical Moment

When scientists experience “mystical moments,” such breakthroughs usually occur when a scientist discovers something remarkable about the physical world. However, some scientists attest to a different kind of mystical (aha) moment that involves the natural, elegant interplay among the human mind, mathematics, computation, and complex instruments. How do we account for this mystical connection? Can naturalism explain it, or is it more consistent with Christianity?  

The mystical moment came while I was visiting Brookhaven National Laboratory. . . . I wound up alone, standing on a jerry-rigged observation platform above a haphazard mess of magnets, cables, and panels. . . . And then it happened. It came to me, viscerally, that the intricate calculations I’d done using pen and paper (and wastebasket) might somehow describe this entirely different realm of existence—namely, a physical world of particles, tracks, and electronic signals, created by the kind of machinery I was looking at. There was no need to choose, as philosophers often struggled to do, between mind or matter. It was mind and matter. How could that be? Why should it be? Yet I somehow, I suddenly knew that it could be so, and should be so (emphasis added).

How did Wilczek’s paper and pencil scribblings have any connections to the unbelievably complex mass of heavy equipment that make up the accelerator ring and detectors of a particle collider, and the data that the huge contraption produced?

While on a short-term work assignment at Fermi National Lab near Chicago, I was given a personal tour of their CDF detector. I was overwhelmed by the massive three-story structure. Yet that huge machinery somehow reflected the mathematical theories that came out of the minds of a group of humans and from the numbers plugged into their mathematical equations and cranked through their computer algorithms. This process—the interplay of mind, mathematics, numerical computation, and experimental machinery—is a mystical feedback loop that lies at the heart of science and propels the accumulation of knowledge.

Humans’ Unique Ability to Discern Truth and Understand the Universe
Physicist Paul Davies finds it remarkable that “the physics of the Universe is extremely special, inasmuch as it is both simple and comprehensible to the human mind” (emphasis original).5 In addition, the mathematics and algorithms are comprehensible and computable, and the results give us understanding of the physical realm.  However, our ability to perceive these truths does not necessarily come from rational, logical, or programmable thought processes. There are some truths that we just innately come to know.

Philosopher Kenneth Samples has identified a set of truths that cannot be verified algorithmically or scientifically: logical truths, metaphysical truths, and objective moral truths.6 Some truths must simply be accepted to be able to do science at all. John Barrow describes physicist Roger Penrose’s view:

An interesting case study to consider is the widely publicized claim of Roger Penrose that human thinking is intrinsically non-algorithmic . . . It amounts to the claim that the process by which mathematicians “see” that a theorem is true, or a proof is valid, cannot itself be a mathematical theorem . . . Penrose concludes . . . that human mathematicians are not using a knowably sound algorithm to ascertain mathematical truth.7 (emphasis original)

In addition, astrophysicist Jeff Zweerink shows how we sometimes rely on intuitive and nonrational thinking to arrive at creative solutions, and he recounts his own experience in doing so.8 From these considerations, we arrive at this conclusion: Humans can discern the truth of a variety of abstract ideas without employing the tools of logic, formal mathematics, or even rational reasoning.

The Only Plausible Explanation: Humans Were Made in the Image of God
During my years as a student at the University of Texas at Austin, I must have walked past the main building more than a hundred times. Very prominently across the facade is the phrase: “Ye Shall Know the Truth and the Truth Shall Make You Free.” Occasionally I would marvel that this promise from Jesus in John’s gospel is thought to have meaning to the overwhelmingly secular culture on campus. Yet, some innate ability to discern truth is necessary for the accumulation of knowledge. However, the ontology (the nature of being) of materialistic naturalism, if truly believed, would lead down into a skeptical abyss. What’s the knowledge potential of a brain that’s the result of incremental and undirected evolution and is located on an arbitrary branch of the evolutionary tree, not far from that of a monkey?

What gave that “human animal” the mind and ability to merge the laws of nature with mathematics, numbers, and computation to form a deep understanding of the physical world? There is no preferred direction or outcome in evolutionary biology, yet that process (supposedly) produced that remarkable achievement. Materialistic naturalism has no plausible explanation. The Bible has the explanation and even secular scientists—while denying God’s existence—must adopt elements of a biblical worldview to do their creative work of discovery.

Endnotes

John Barrow,  Pi in the Sky: Counting, Thinking, and Being  (Boston: Little Brown and Company, 1994).The significance of this lecture is discussed in James Gleick’s book  Genius: The Life and Science of Richard Feynman  (New York: Vintage Books, Random House, 1992), 182–183. The lecture has been published in  The Feynman Lectures on Physics, Volume I, Chapter 22 ,  https://www.feynmanlectures.caltech.edu/I_22.html, accessed September 6, 2022.David Berlinski,  A Tour of the Calculus  (New York: Vintage Books, Random House, 1995), 47–49.A good example of a simple computational algorithm is the numerical evaluation of a square root. See “Newton’s Iteration,” Wolfram MathWorld, https://mathworld.wolfram.com/NewtonsIteration.html, last updated August 22, 2022.Bernard Carr, ed.,  Universe or Multiverse  (New York: Cambridge University Press, 2007), 494.Kenneth R. Samples,  Christianity Cross-Examined: Is It Rational, Relevant, and Good?  (Covina, CA: RTB Press, 2021), 46–49.Barrow, Pi in the Sky, 285.Jeff Zweerink, “Does Human Reasoning Demonstrate Exceptionalism?,” Impact Events (blog), Reasons to Believe, June 10, 2022.

Full article at Reasons.org.

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At Earth Sky: How likely is an Earth-like origin of life elsewhere?

Paul Scott Anderson writes:

We know that life originated on Earth some 3.7 billion years ago. But we still don’t understand exactly how life came to be. Likewise, we know little to nothing about life on other rocky worlds, even those that might be similar to Earth. Is life a rare occurrence, or is it common? Or somewhere in between? Scientists debate the subject of abiogenesis, the idea of life arising from non-living material. If it can happen on Earth, can it happen elsewhere, too? A new paper from retired astrophysicist Daniel Whitmire at the University of Arkansas argues that it can.

Whitmire published his new peer-reviewed paper in the International Journal of Astrobiology on September 23, 2022.

Abiogenesis and our own existence

Basically, the paper is a counter-argument to the view held by Brandon Carter, an Australian-born astrophysicist. Carter asserts that our own existence constrains our observations of other worlds where life might exist. What does he mean? Essentially, he says, we ourselves happen to exist on a planet where abiogenesis did occur. But – since we only have our own planet as an example so far – it’s not possible for us to determine how likely it is for life to have emerged elsewhere.

Carter says that Earth can’t be considered “typical” yet … because there’s no set of known Earth-like planets to compare it to.

How likely is an Earth-like origin of life elsewhere?

Scientists tend to be conservative. They don’t like to speculate that something exists until they have the evidence in hand. So many scientists seem to accept Carter’s theory. But Daniel Whitmire doesn’t accept it. He contends that Carter is using faulty logic.

He points to what philosophers call the the old evidence problem. That philosophical problem concerns what happens when a theory or hypothesis is updated, following the appearance of new evidence. Whitmire says basically that Carter doesn’t take into account the long cosmic timescales at play in the universe, for example, the length of time it takes life to emerge on a planet. Whitmire writes:

… The observation of life on Earth is not neutral but evidence that abiogenesis on Earth-like planets is relatively easy. I … give an independent timescale argument that quantifies the prior probabilities, leading to the inference that the timescale for abiogenesis is less than the planetary habitability timescale and therefore the occurrence of abiogenesis on Earth-like planets is not rare.

Note: This attempt at philosophical reasoning stumbles with the loaded presupposition that life on Earth arose by natural processes, even though numerous decades of origin-of-life research have shown that any pathway to life from non-life would be exponentially more complicated than any natural mechanism ever investigated.

In late September, I wrote about recent discoveries that add to the accumulation of evidence that life does indeed exist elsewhere. In other words – from ocean moons like Europa and Enceladus, to the latest understanding of organics and ancient habitable conditions on Mars – conditions for life seem to abound, even here in our own solar system. In the vast Milky Way galaxy beyond, astronomers have discovered many thousands of exoplanets. So we know other solar systems exist. And, to me, as I write about these discoveries, the odds seem pretty good that life is out there somewhere.

Here’s another example from the realm of exoplanets. New studies suggest that some (or many) super-Earths might exist as water worlds that aren’t just habitable, but potentially even more habitable than Earth. Some may even be completely covered by oceans.

Whitmire and Carter’s approach – a philosophical approach – to the question of life on other worlds is interesting. But, as the philosophers argue the question, the pace of scientific discovery continues. And many scientists believe we’re now on the verge of finding our first definitive evidence of alien life. Some think it will come within the next decade or two … or sooner.

If Whitmire is right, that first discovery will be exciting indeed.

Earth Sky

Optimism about the possibility of extraterrestrial life has always been popular. However, for a natural mechanism to be able to generate the amount of information found in the vast amounts of biochemical complexity within a “simple” cell, known laws of physics would have to be violated. Ideas which violate established science are usually bogus, unless they’re simply refinements that apply in certain limits of physical parameters. (Such as Einstein’s theory of relativity, which modified Newton’s laws of mechanics in the limit of speeds approaching the speed of light.)

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L&FP, 62: The Systems (and Systems Engineering) Perspective — a first step to understanding design in/of our world

Our frame going forward, is knowledge reformation driven by application of the adapted JoHari Window, given obvious, fallacy-riddled ideological captivity of the intellectual high ground of our civilisation:

Ideological captivity of the high ground also calls forth the perspective that we need to map the high ground:

[image error]

If you want some context on validity:

So, we are now looking at ideologically driven captivity of the intellectual high ground and related institutions of our civilisation, leading to compromising the integrity of the knowledge commons through fallacy riddled evolutionary materialistic scientism and related ideologies. Not a happy thought but that is what we have to deal with and find a better way forward.

We already know, knowledge (weak, everyday sense) is warranted, credibly true (so, reliable) belief, and that it is defeasible on finding gaps or errors that force reworking. Classically, that happened twice with Physics, the shattering of the Scholastic view through the Scientific revolution, and the modern physics revolution that showed limitations of newtonian dynamics and classical electromagnetism. Physics, like Humpty Dumpty [and the underlying fallen Roman Empire], has never been put back together again.

But, how do we proceed?

Through systems thinking and systems engineering, on several levels.

First, NASA defines:

“systems engineering” is defined as a methodical, multi-disciplinary approach for the design, realization, technical management, operations, and retirement of a system. A “system” is the combination of elements that function together to produce the capability required to meet a need. The elements include all hardware, software, equipment, facilities, personnel [–> thus, these are sociotechnical systems and bridge engineering and management], processes, and procedures needed for this purpose; that is, all things required to produce system-level results. The results include system-level qualities, properties, characteristics, functions, behavior, and performance. The value added by the system as a whole, beyond that contributed independently by the parts, is primarily created by the relationship among the parts; that is, how they are interconnected. [–> functional, information rich organisation adds value] It is a way of looking at the “big picture” when making technical decisions. It is a way of achieving stakeholder functional, physical, and operational performance requirements in the intended use environment over the planned life of the system within cost, schedule, and other constraints. It is a methodology that supports the containment of the life cycle cost of a system. In other words, systems engineering is a logical way of thinking.

Systems engineering is the art and science of developing an operable system capable of meeting requirements within often opposed constraints. Systems engineering is a holistic, integrative discipline

NASA has a big scoping chart for Systems Engineering in a project/programme management context:

We can look at the Systems Engineering Vee Model (HT: ResearchGate):

Another view, notice, the implied, layer cake modularity of systems, from physical materials to base devices and components [consider a transistor or a bolt], to function units, to system modules and organisation to overall functionality based on information rich organisation:

In that context, we can bring on board issues of systems architecture and related matters, as I commented earlier today:

An Analogue Computer network with two chained integrators

Computer architecture at first level, is the study of the assembly/machine language view, i.e. information, its processing [including coding, algorithmic processes etc], associated function units, their organisation. Underlying physical science and technique to effect these units carries us to the layer cake, modular network, systems view. With analogue computers, the focus is on continuous state function units and how they represent key mathematical operations [famously, integration] that then integrate in a process flow network to handle continuous state information bearing signals and materials or states and phases of dynamic stochastic entities etc. This extends the context to instrumentation, control and systems engineering as well as telecommunications, bringing in frequency domain transforms and approaches as well as state/phase space approaches. These give us fresh eyes to see and more objectively understand the molecular nanotech marvels in the cell.

Obviously, this immediately allows us to reconsider the cell as a marvel of nanotechnology, e.g. here is its metabolic framework, part of how it is a metabolising, molecular nanotech self replicating automaton:

Just the top left corner, already involves a complex algorithmic process using coded information:

Protein Synthesis (HT: Wiki Media)

Then, there is the communication network this expresses, as Yockey pointed out:

Yockey’s analysis of protein synthesis as a code-based communication process

All of this, we have known for decades, but now it is time to independently ponder it as a system and understand how this exemplifies and instantiates such system elements. We can immediately set aside crude fallacies of appeals to dismissible analogies, once we ponder, say, the genetic code as just that, a code:

The Genetic code uses three-letter codons to specify the sequence of AA’s in proteins and specifying start/stop, and using six bits per AA

Just for reference, by fair use doctrine, here is Lehninger’s comparison:

By starting from a systems perspective, we can then rebuild knowledge on a sounder footing than the present ideologically driven institutional capture. END

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At Reasons.org: Was Earth Designed for Us or Did We Evolve to Adapt?

Astrophysicist Hugh Ross writes:

Reasons.org

My answer: I get asked this question nearly every time I speak on a university or college campus. Apparently, the hypothesis that humans became compatible or naturally evolved to adapt to Earth’s present conditions has become dogma in many university course offerings, more so in the social sciences than in the physical or life sciences. Consequently, I devoted an entire book to answering this question, Improbable Planet.1 Additional evidences that our supergalaxy cluster, our galaxy cluster, our galaxy group, our galaxy, the Local Bubble, the Local Fluff, the solar system, and the Sun, Moon, and Earth have been exquisitely prepared and designed for humans are presented in my next book, Designed to the Core.2

A very brief answer is that the Milky Way Galaxy, the solar system, and Earth were designed to be the ideal home for humanity and global human civilization millions and billions of years before humans showed up. More than 400 distinct features of Earth must be fine-tuned to make our existence and civilization possible.3 Even with all this exquisite fine-tuning the time window during which humans can exist in a civilized state is extremely narrow.4 It is no random accident that we happen to be here during this narrow time window when the resources we need to sustain global civilization are uniquely available.

Endnotes

Hugh Ross,  Improbable Planet  (Grand Rapids, MI: Baker Books, 2016).Hugh Ross, Designed to the Core (Covina, CA: RTB Press, 2022).Hugh Ross, “RTB Design Compendium (2009),” Reasons to Believe (November 16, 2010).Hugh Ross, Weathering Climate Change (Covina, CA: RTB Press, 2020), 167–186.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.
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At Live Science: Mysterious ‘ancient heart’ of the Milky Way discovered using Gaia probe

Ben Turner writes:

Astrophysicists investigating the origins of the Milky Way may have discovered our galaxy’s ‘old heart’ — the original, ancient nucleus around which all of its stars and planets grew.

The Milky Way’s central region, where Sagittarius and the group of ancient stars can be found, above Telluride, Canada. (Image credit: John Sirlin/Alamy Stock Photo)

The collection of 18,000 of our galaxy’s oldest stars are located in the constellation Sagittarius are from the Milky Way’s protogalaxy — a primordial mass of gas and dust forming the first stars of a young galaxy — that is more than 12.5 billion years old. Accounting for an estimated 0.2% of our galaxy’s total mass, the group is the kernel around which all of the Milky Way eventually grew, the researchers found. The findings were published on Sept. 8 on the preprint server arXiv, and are yet to be peer-reviewed.

To discover the primordial group of stars, the astronomers drew on data from the European Space Agency’s (ESA) Gaia observatory — a 3594-pound (1,630 kilograms) spacecraft launched in 2013 with the goal of creating the most detailed and accurate map of the Milky Way. 

“It has long been believed (on the basis of theory and simulations) that the very oldest stars are at the very center of a galaxy. We have now shown them to be there in great numbers,” study lead author Hans-Walter Rix, an astronomer at the Max Planck Institute for Astronomy in Heidelberg, Germany, told Live Science. “It’s like doing archeology in an old city. We have shown that the oldest and most primitive ruins are at the ‘modern’ city center.”

Finding our galaxy’s ancient heart began with searching the most crowded region, its central bulge, for the tiny proportion of stars around the same age as the roughly 13 billion-year-old Milky Way. 

To pluck this tiny group like a needle from a haystack, the researchers pulled together data collected from Gaia on 2 million stars that sit within 30 degrees of the galactic center, searching for lower-mass, longer-lived stars with low metal content. Stars matching this profile were birthed in a much younger universe that was not yet filled with heavy metals scattered far and wide by supernova explosions.

But this is only one half of the story, as metal-poor stars within the Milky Way may also have come from smaller dwarf galaxies that smashed into and merged with our galaxy throughout its life. By examining these stars’ paths through space while retaining only those that didn’t veer out into the metal-poor regions of the galaxy, the researchers were able to separate out the stars that form the ancient heart from the stars that originated in a dwarf galaxy. 

The researchers’ examination of the Milky Way’s now-exposed ancient heart revealed two things. Firstly, as stars of the old protogalaxy rotate much less around the galactic center compared with younger stars, it confirms past observations that the Milky Way’s core began its life stationary, eventually picking up rotational speed as the galaxy’s center of mass grew.

And secondly, in spite of multiple mergers with smaller galaxies, the close bunching of stars in the Milky Way’s center points to its core not having been invaded by collisions from other galaxies.

“The Milky Way never has been shook up dramatically,” Rix said. “Our galaxy has lived a sheltered life.”

With further study, the researchers hope the ancient heart can teach them even more about our galaxy’s earliest years, such as the types of supernovas that must have exploded during the time of its creation to produce the proportions of early chemical elements we see today.

Live Science

Studies of our galaxy have revealed that numerous features of the Milky Way appear to be unique compared to most galaxies in giving our solar system a unique environment suitable for sustaining life on Earth in its various forms over the course of Earth’s history. In connection with merger events with smaller galaxies, astrophysicist Hugh Ross provides this comment:

This “undisturbed” quality appears to be fine-tuned. An outstanding MWG feature is that throughout its past 11 billion years it has not suffered any merger events of sufficient magnitude to alter its spiral structure in any life-threatening manner. Nevertheless, it has accreted sufficient streams of gas and a sufficient number and rate of low-mass dwarf galaxies to sustain its spiral structure. Without such regular accretions a spiral galaxy’s spiral structure collapses after only 3–4 galactic rotations.

Reasons.org

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At Sci News: Mars was Habitable for Methanogenic Microorganisms 3.7 Billion Years Ago, Study Suggests

The potential habitability of early Mars, more than 3.7 billion years ago, has been extensively debated.

Evidence suggests that the planet hosted — at least for part of its history — potentially favorable conditions for the development of life.

The young Mars would have had enough water to cover its entire surface in a liquid layer about 140 m deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars’s northern hemisphere, and in some regions reaching depths greater than 1.6 km.
Image credit: M. Kornmesser / ESO / N. Risinger, skysurvey.org.

“During the Noachian, Mars’ crust may have provided a favorable environment for microbial life,” said Dr. Boris Sauterey, a researcher in the Department of Ecology & Evolutionary Biology at the University of Arizona and the Institut de Biologie de l’Ecole Normale Supérieure at the Université Paris Sciences et Lettres, and his colleagues.

“The porous brine-saturated regolith would have created a physical space sheltered from ultraviolet and cosmic radiation and provided a solvent, whereas the below-ground temperature and diffusion of a dense, reduced atmosphere may have supported simple microbial organisms that consumed hydrogen and carbon dioxide as energy and carbon sources and produced methane as a waste.”

“On Earth, hydrogenotrophic methanogenesis was among the earliest metabolisms, but its viability on early Mars has never been quantitatively evaluated.”

In their study, the authors modeled the interaction between the early Martian environment and an ecosystem of methanogenic hydrogenotrophs — microorganisms that survive by consuming hydrogen and producing methane — which are considered to be among the earliest forms of life on Earth.

Their simulations predict that the Martian crust was a viable place for this ecosystem — provided that the surface was not fully covered with ice — and could have produced biomass similar to that of the early ocean of Earth.

They predict that this ecosystem would have triggered a feedback event with the climate on Mars, cooling it globally by up to 40 Kelvin and creating less habitable conditions closer to the surface.

This would have forced the microbes to move progressively deeper within the planet’s crust.

Looking forward, the researchers identified three sites — Hellas Planitia, Isidis Planitia and Jezero crater — as the best places to look for signs of this early methanogenic life near the surface of Mars.

“We find that subsurface habitability was very likely, and limited mainly by the extent of surface ice coverage,” they said.

“Biomass productivity could have been as high as in the early Earth’s ocean.”

“However, the predicted atmospheric composition shift caused by methanogenesis would have triggered a global cooling event, ending potential early warm conditions, compromising surface habitability and forcing the biosphere deep into the Martian crust.”

“Spatial projections of our predictions point to lowland sites at low-to-medium latitudes as good candidates to uncover traces of this early life at or near the surface.”

A paper on the findings was published in the journal Nature Astronomy.

Sci News

Is there an implicit assumption here that abiogenesis occurs whenever possibly habitable conditions exist? What is the scientific basis for making such an assumption? Or is this an example of making a nonscientific extrapolation from available evidence? What if scientific evidence was presented, and an extrapolation was made from that evidence to a non-natural intelligent agent as a cause?

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“A Seat at the Table”

A recent comment to one of the posts on Uncommon Descent states that nothing like an atheistic censorship committee exists to unfairly block out scientific arguments for ID. The comment maintains that ID simply needs to produce a sufficiently compelling argument in order to earn “a seat at the table.”

Let’s run with this a little. Imagine a school cafeteria, with one of those big, long tables where all the popular kids sit for lunch. If you didn’t belong to that crowd, you probably can immediately feel the unspoken barriers that make your attempt to sit at the table most unwelcome.

Now, in the scientific community, the rules are not unspoken. As stated in my book, Canceled Science: What Some Atheists Don’t Want You to See, (p. 51) the rules are spelled out in bullet-point format. The first one states: “Modern science seeks explanation for observed phenomena that rely solely on natural causes.” As one who has made a career as a physicist for several decades, I would of course concur with this, in general. But what if the observed phenomenon is not consistent with natural causes?

Back to the table…

Would the popular kids (mainstream scientific academies) be open to even considering a conclusion that doesn’t “rely solely on natural causes”? These days, the evidence says, “No.”

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At Evolution News: Secrets that Give Sea Lions and Jellyfish Their Edge as Swimmers

David Coppedge writes:

The Illustra Media documentary Living Waters focuses on four marine organisms, each worthy of admiration: dolphins, sea turtles, salmon, and humpback whales. But before and after the detailed accounts, scenes of many other swimmers parade across the screen. Can you guess which of them wins the prize for most efficient swimmer? It may not be your first guess. It’s not necessarily the fastest, just the one that gets the most distance per expenditure of energy.

Neelesh Patankar, a mechanical engineer from Northwestern, and John Dabiri, a bioengineer from Caltech, measured the efficiency of a wide variety of organisms. They determined that top prize goes to: the jellyfish. In an article at The Conversation, Akshat Rathi explains why jellyfish “are the most efficient swimmers” in the world. That’s quite a distinction among the many other swimmers that are already at the top of their game:

The new measure has two implications. First, among those that have typical swimming and flying actions, which includes most fish and all birds, each animal is as energy efficient as it can be. This means that, given their size and shape, each animal is able to spend the least amount of energy to move the most distance. Second, this measure confirms a previous finding that jellyfish are unusually energy efficient, beating all the thousands of fish and birds Patankar studied.

“Put another way, a whale and a tuna are equally energy efficient,” Patankar said. “Except jellyfish, which have an unusual action that makes them more efficient.” [Emphasis added.]

What’s the Secret?

Beautiful images of these creatures flash by briefly in the Illustra film. Time did not allow producer Lad Allen to discuss their mechanics, but the subject was considered during the planning stages. We mentioned jellyfish efficiency in an earlier post. What’s the secret that gives jellies the edge?

While working on the energy-consumption coefficient, he came across recent work done by Dabiri and his colleagues which showed that the unique contract-and-relax action of jellyfish allowed it to recapture some of the energy it spends on motion. This means a jellyfish can travel a lot more distance for the same amount of energy spent by other animals adjusted for its weight and size.

The Cambrian Explosion

It’s interesting to note, also, that jellyfish (phylum Cnidaria) are among the phyla that appear abruptly in the Cambrian explosion — see our article where an expert said, “The earliest widely accepted animal fossils are rather modern-looking cnidarians.” Given the high efficiency of these deceptively simple-looking animals, it’s not surprising that engineers are attempting to imitate their secrets. “Dabiri is already working on exploiting jellyfish propulsion,” Rathi says.

There’s another swimmer that might surprise you, this time for its stealth. These graceful animals make cameo appearances at the beginning and end of Living Waters. Phys.org reports:

At a maximum speed of 25 miles per hour, sea lions may not be the fastest-swimming mammal in the sea. But they are unrivaled when it comes to stealth — their signature clap-and-glide flipper motion propels them through water and leaves virtually no wake.

The benefits of turbulence-free motion underwater are obvious. Imagine submarines that glide stealthily beneath sensitive detectors. At George Washington University, mechanical engineers and students are attempting to “build a machine to mimic what sea lions naturally do.” 

It wouldn’t be easy to design a system from scratch that could match the sea lion’s specifications — they produce high levels of thrust while leaving little traceable wake structure. So it makes sense to learn as much as we can about how they do it — with the thought that someday we might be able to engineer something that mimics our biological model.

The secret of wake-free swimming appears to be related to the sea lion’s use of its fore-flippers, rather than a tail (as with dolphins and fish). At The Conservation, Megan Leftwich describes in more detail how this mode of locomotion produces more thrust. A video shows how researchers at George Washington University are measuring carefully the flipper motions of California sea lions, mapping them into computer models that can inform the design of artificial flippers. This is an exercise in “Studying Nature’s Solutions,” the title says.

If the world’s best human designers are attempting to build machines to mimic what these animals “naturally do,” it’s a reasonable inference that sea lions and jellyfish originated from an intelligent cause — one with superior knowledge of propulsion, fluid mechanics, and optimization.

Evolution News

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