Michael J. Behe's Blog, page 43

At Big Think: Can we predict evolution?

We can successfully predict the future arrangements of matter based on knowledge of the laws of physics that govern the interactions between particles. When too many particles exist to make detailed predictions about individual particles, we can use statistical physics to predict generally true and reliable outcomes of the larger system of particles. The 2nd law of thermodynamics provides us with a familiar example of outcomes based on statistical physics. If the future forms of living organisms are predictable, it will likewise be due to the ensemble of their systems of particles obeying fundamental laws of physics. “Evolution” is not a “law of physics” that is independent of or supersedes other known laws of physics.

Organisms respond in similar ways to similar circumstances.

KEY TAKEAWAYS

Evolution has long been viewed as a largely unpredictable process, influenced by chaotic factors like environmental disruptions and mutations. However, researchers have demonstrated cases in some organisms of “replicated radiation,” in which similar sets of traits evolve independently in different regions. Now, researchers report the first evidence for replicated radiation in a plant lineage. As biology learns more about phenomena like replicated radiation, we might be able to predict the course of evolution.

Evolution has a reputation for being unpredictable, yet orderly. With mutations and the environment playing huge roles, it seems that predicting which species will evolve which traits is much like guessing the roll of a single die with millions of faces. 

However, in some cases, researchers have found that the die rolls the same way again and again. A combination of separate organisms’ natural development and the environmental pressures placed on them can create very similar forms, or ecomorphs. Researchers call this phenomenon replicated radiation. (Sometimes, the term adaptive radiation is used synonymously.)

In a new paper published in the journal Nature Ecology & Evolution, an international group of researchers demonstrated that a plant lineage living in 11 geographically isolated regions independently evolved new species with similar leaf forms. This marks the first example of replicated radiation in plants, and the groundbreaking research gives us more insight into the possible future workings of evolution. 

Note: Reason suggests that the development of “similar leaf forms” stems from the fact that they all started from the same “plant lineage.” Furthermore, reason suggests that the original plant lineage had a built-in genomic variability that allowed the variant leaf forms to dominate when environmental pressures favored that form.

Credit: Annelisa Leinbach / Big Think

The article continues: Different species of Oreinotinus [Viburnum] have different types of leaves. Simply put, some have a large, hair-covered leaf, and others have a smaller, smooth leaf. Originally, experts postulated that both leaf forms evolved early in the group’s history and then dispersed separately through various mountain ranges, carried perhaps by birds. But the distribution pattern of the species, combined with the striking differences in leaf traits, gave researchers an ideal system to explore the possibility that these leaf forms evolved independently across different regions. In other words, they could explore whether this was a case of replicated radiation.

If replicated radiation is occurring, the researchers would expect two key results. First, species in the same area should be more closely related to each other than to species in different regions. Second, similar leaf traits should be present in most areas, but they should evolve independently of one another.

Turning over the same leaf

As Oreinotinus diversified, four major leaf types evolved independently from an ancestral leaf form. The four forms varied in size, shape, margin — that is, whether the edge of the leaf is smooth or toothed — and the presence of leaf hairs. The study grouped the leaves into four types. The researchers also backed up their assessments with a statistical analysis based on these characteristics. 

Nine of the 11 areas harbor at least two leaf forms; four areas include three forms; and one, Oaxaca, is home to four. Based on simulations and models, the authors rejected the simple evolutionary model in which the leaf forms evolved before the species dispersed. They also found that chance alone does not likely explain why nine areas of endemism host two or more leaf forms. Based on these lines of evidence, the team concluded that leaf forms evolved separately within multiple regions. The leaf morphs did not originate early in Oreinotinus evolution. Rather, as different lineages diversified within different areas, each lineage “traversed the same regions of leaf morpho-space.”

So what is this clade telling us when it evolves different leaf forms? As it turns out, different leaves provide different advantages that suit particular climate niches. For example, the smaller leaves would allow more precise thermoregulation — the leaf won’t get too hot or too cold as the weather changes. On the other hand, large leaves would be better for lower-light, frequently cloudy environments, because they improve light capture and make photosynthesis more efficient. So the different leaf ecomorphs are adapted to specific sets of subtly different but often adjacent environmental niches.

The future of evolution

Researchers can now add Oreinotinus to an exclusive list of other groups of organisms known to have undergone replicated radiation, such as Anolis lizards in the Caribbean, cichlid fishes in African rift lakes, and spiders in Hawaii.

With a plant on the list, evolutionary biologists know this is not a trend exclusive to animals isolated on islands, where most of the other examples come from. Like island archipelagos, the cloud forest environments of Oreinotinus are separate from one another. A plant example will help evolutionary biologists pinpoint the broad circumstances under which we can make solid predictions about evolution.

Whether it’s Darwin’s finches, Oreinotinus, or a group of sugar-hungry E. coli, we are all subject to the mysterious workings of evolution. But perhaps, as a diverse set of research groups work to tackle the problem, the mystery will fade. As Michael Donoghue, a co-corresponding author of the Oreinotinus  study, said in a statement, “Maybe evolutionary biology can become much more of a predictive science than we ever imagined in the past.”

Full article at Big Think.

Predictive success alone does not guarantee the success of a theory of how nature works. Additional consequences of a theory must also make sense and not contradict established laws of nature. Naturalistic evolution still contradicts the principle that natural causes will on average degrade the information content (loss of functional complexity) of a system over time.

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At Mind Matters News: Is ours one of a few working universes among countless flops?

Is that probable? How would we know? Philosopher Stephen C. Meyer offers some suggestions:

In the case of the inflationary cosmology, both the shutoff energy and the time interval in which that shutoff occurs have to be precisely finely tuned to generate a new universe, even in theory. In the string theoretical landscape, multiple things have to be finally tuned — the most important of which is setting the first possible universe at the highest energy level so it can cascade down the landscape to explore all the other possible ones. So that all the different universes eventually are instantiated or come into existence.

Even though the multiverse is attempting to explain the fine tuning, it actually ends up presupposing prior sources of unexplained fine tuning. And therefore it doesn’t ultimately explain the fine tuning; it just pushes the fine tuning problem back one generation… Except that there is one thing we know from experience that always produces fine tuning, or that is always associated with fine tuning, and that’s intelligence. Think of the other systems that we would say are finely tuned, a fine French recipe, an exquisite Swiss clock, or watch. Any fine piece of machinery, an internal combustion engine. Digital code in the software program, or the fine tuning that we see in the universe.

News, “Is ours one of a few working universes among countless flops?” at Mind Matters News (August 28, 2022)

Takehome: No. For one thing, Meyer says, even though the multiverse attempts to explain fine tuning, it actually ends up presupposing unexplained prior sources of fine tuning.

Here’s the first portion: If DNA is a language, who is the speaker? Philosopher Steve Meyer talks about the significance of Francis Crick’s sequence hypothesis that showed that DNA is a language of life. What sort of speaker can utter a language that produces living beings? Is it a fluctuation of a multiverse or an intelligence that underlies nature?

And the second: Has a superintellect monkeyed with our universe’s physics? Groundbreaking astronomer Fred Hoyle was a staunch atheist but then he tried showing that carbon, essential to life, could form easily… It got worse: To form carbon at all, gravitational forces must be balanced just right with the electromagnetic forces. That’s just the start…

The third: How fine tuned was our universe’s debut? The mind boggles. All the details that were there at the beginning and all work together… The math is amazing. The fact of fine-tuning — both of forces and their relationships — is generally accepted, irrespective of physicists’ religious views or lack thereof.

You may also wish to read: Theoretical physicist: Can’t avoid a beginning for our universe. Recent shakeups from the James Webb Space Telescope images invite fundamental questions like, Does the universe even have a beginning? The big Telescope made new data available, some of it “amazing.” And if it had only confirmed what we know, how would we know it had ever left the launch pad?

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Cold Case Detective J. Warner Wallace on the “God of the Gaps”

J. Warner Wallace: at HillFaith:

One of the most commonly cited criticisms of those who believe human beings, Earth and indeed the entire universe exhibit evidence of intelligent design is the retort from evolutionists that concluding there must be a designer is “just another example of the ‘god of the gaps’ fallacy.”

On the surface, the god of the gaps accusation has a patina of intellectual credibility, but a closer examination of the evidence and reasoning for the designer conclusion reveals that it is a logical conclusion, not an assumption in the nature of a substitution to fill an evidentiary void.

Essentially, as Cold-Case Christianity’s J. Warner Wallace, the retired Los Angeles Police Detective who specialized in solving murder cases that had remained unsolved for year, explains, particular evidence requires certain characteristics in order to have explanatory power.

“Here’s Why the ‘God of the Gaps’ Critique is a Mis-Characterization of Theism, Intelligent Design” at HillFaith (August 28, 2022)

Also at HillFaith (an outpost of reason at U.S. Capitol):

“On the Trap of the ‘God of the Gaps,” Dr. William Lane Craig

“Can Intelligent Design be Empirically Detected?” Summit Ministries

“The Return of the God Hypothesis,” Stephen Meyer interviewed by Dr. Sean McDowell

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Live Not By Lies

The North Korean government claims Kim Jong Il made 11 holes-in-one in his first golf game. For a long time I wondered why they bother making up such outrageous lies. Then one day I realized that the very outrageousness of the lie IS the point.

Every tyrant’s power is built on a foundation of lies, and therefore tyrants must always condition their victims to the subjugation of lies. The more outrageous and unbelievable the lie, the better. Because the more outrageous the lie, the more the light in the victim’s soul fades when he repeats it, and as that light fades so too does his will to resist.

The point of the 11 holes-in-one story is not that anyone believes it. The point is that no one believes it. And every North Korean affirms what they know not to be true because they are afraid of the consequences if they do not.

The tyrant demonstrates he has true power over you if he is able to force you to murder your own soul.

Remember that the next time a progressive tries to berate you into affirming the lie that a man is in fact a woman

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At Reasons.org: Have Astronomers Found Life’s Building Blocks?

Astrophysicist Hugh Ross reports:

For at least five decades, proponents of a naturalistic origin of life have been searching for evidence of the RNA world hypothesis. The RNA world is a proposed step in the evolution of life on Earth in which self-replicating RNA molecules preceded genetic material and proteins. Life on Earth appeared suddenly about 3.8 billion years ago. However, evidence for organic molecules that could possibly give rise to RNA is lacking on Earth; thus, astrobiologists believe the building blocks of life must reside in interstellar space.

Precursor Molecules
In 1969, a team of four astronomers led by Lewis Snyder discovered formaldehyde (H2CO) in an interstellar molecular cloud.1

Two months ago, the list of discovered distinct carbonaceous organic polyatomic molecules found in interstellar molecular clouds stood at 152.3

Now, astronomers have added four nitriles to the list.4 Nitriles are a class of organic molecules with a cyano group. A cyano group is a carbon atom bound with a triple unsaturated bond to a nitrogen atom. Cyanos are typically very toxic. Sodium cyanide and potassium cyanide are well-known examples.

One of chemistry’s great enigmas is that nitriles are key precursor molecules of the nucleobases, which when joined to a ribose and a phosphate molecule comprise the fundamental building blocks of RNA and DNA molecules. RNA molecules together with DNA molecules, proteins, and lipids are the molecules every organism possesses and without which no life-form can possibly survive.

Discovered Nitriles
A team of thirteen astrobiologists led by Victor Rivilla used the world’s most sensitive millimeter-wave radio telescopes, the IRAM 30-meter and the Yebes 40-meter telescopes in Spain, to search in the giant molecular cloud, G+0.693-0.027, near the center of our galaxy 26,673 light-years away for the spectral signatures of seven nitriles.5

Rivilla’s team detected the following four nitriles: cyanic acid, cyanoallene, propargyl cyanide, and cyanopropyne.

The measured abundance levels for the detected nitriles were very low. Even the simplest one, cyanic acid (HOCN), measured rare. Rivilla’s team determined that in G+0.693-0.027 there is only one molecule of cyanic acid for every 6 billion molecules of molecular hydrogen (H2).8

Origin of Life Implications
The British newspaper, The Telegraph, in the headline of their report on the Rivilla team’s discoveries stated that the “building blocks of life” found by the team “suggests we are not alone.”10 One of Rivilla’s coauthors, Miguel Requena-Torres, was quoted as saying to Sarah Knapton, science editor for The Telegraph, “We now know that nitriles are among the most abundant chemical families in the universe.”11 By “chemical families,” Requena-Torres had to be referring to precursor molecules for nucleobases and amino acids. Another coauthor, Izaskun Jiménez-Serra, referring to such precursor molecules, said “There are still key missing molecules.”12

In the conclusion to their paper, Rivilla’s team noted that nitriles are not a direct precursor to either nucleobases or amino acids. The early Earth’s atmosphere would need to have been chemically reducing and must have contained high amounts of ammonia for amidines to possibly form from nitriles. Several amidines are direct precursors for nucleobases and amino acids. However, as we explained and documented in our book Origins of Life, Earth’s early atmosphere was neither reducing nor did it contain more than a trace amount of ammonia.13

What Ravilla’s team found were a few of the hundred-plus molecules that are the “building blocks of the building blocks of the building blocks” of life molecules. They found them at abundance levels far below what is needed for any conceivable naturalistic model for life’s origin. And they found them in an interstellar molecular cloud where the chemical reactions that produce them are counterbalanced by chemical reactions that destroy them.

Thus, Ravilla’s team’s detections do not, as they claim, provide support for the RNA world hypothesis for the origin of life.

Rather, their detections provide additional confirmation for what Fazale Rana and I heard Leslie Orgel, the father of the RNA world hypothesis, say in the opening plenary session message at the 2002 International Society for the Study of the Origin of Life conference, “It would be a miracle if a strand of RNA ever appeared on the primitive Earth.”

What seems miraculous from a naturalistic perspective can be explained from a creation perspective as the work of a supernatural Creator. As proclaimed in Psalm 104:24, “How many are your works, Lord! In wisdom you made them all; the earth is full of your creatures.”

Full article at Reasons.org.

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At Mind Matters News: Astrophysicist: Webb finds may bring “revolutionary changes”

It doesn’t disprove the Big Bang, says Brian Koberlein… but read the fine print. Fermilab’s Don Lincoln gets the religious implications all wrong:

Whoops! The history is quite different from what Dr. Lincoln must suppose. Originally, materialist atheists opposed the Big Bang precisely because it seemed too much like creationism or theism. But the available evidence supported it, which pleases most theists.

Some scientists who are theists have even built significant ministries around advocating the Big Bang as a reason for belief. Of all parties, that last group has the most to lose if the pattern of evidence changes. C’est la vie…

Straight-shooting theoretical physicist Sabine Hossenfelder, author of Lost in Math: How Beauty Leads Physics Astray, takes the view that we don’t know and never will:

News, “Astrophysicist: Webb finds may bring“ revolutionary changes”” at Mind Matters News

You may also wish to read:

Theoretical physicist: Can’t avoid a beginning for our universe. Recent shakeups from the James Webb Space Telescope images invite fundamental questions like, Does the universe have a beginning? The big Telescope made new data available, some of it “amazing.” And if it had only confirmed what we know, how would we know it had ever left the launch pad?

and

James Webb Space Telescope shows Big Bang didn’t happen? Wait… The unexpected new data coming back from the telescope are inspiring panic among astronomers. Webb was expected to merely confirm the Standard Model of the universe but its images are “surprisingly smooth, surprisingly small and surprisingly old.”

Takehome: Theoretical physicist Sabine Hossenfelder thinks we don’t know what happened and never will — and that the Big Bang is a “creation myth” in the language of math

It doesn’t disprove the Big Bang, says Brian Koberlein… but read the fine print. Fermilab’s Don Lincoln gets the religious implications all wrong. Theoretical physicist Sabine Hossenfelder thinks we don’t know what happened and never will — and that the Big Bang is a “creation myth” in the language of math.

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At Mind Matters News: Atheist philosopher strongly supports online political censorship

Supreme Court Justice Thomas has noted that the Court will soon need to address freedom of speech issues in privately owned Big Social Media:

Recently, neuroscientist and philosopher Sam Harris came out in favor of Big Social Media censorship in a Triggernometry YouTube podcast. His comments, as reported in a partial transcript, supported acknowledged BSM efforts to stifle public awareness of of compromising material found on the laptop of Present Joe Biden’s son, Hunter Biden just prior to the U.S. 2020 election: “‘At that point, Hunter Biden literally could have had the corpses of children in his basement – I would not have cared,’ began the best selling author, who specialises in religion, rationality, and ethics…”

In the real world, the surest way to strengthen rumors about election fraud or other high-level misdeeds is to censor those who make the claim.

And here’s another underdiscussed fact: Book, video, and opinion banning creates many new jobs in censorship. Jobs in censorship, unlike those in arts, literature, and science, require literacy and submissiveness rather than creativity or good judgment. That greatly broadens the pool of qualified applicants.

As censorship grows, three things may be expected: 1) It broadens into areas in which it enjoys little public support. 2) It becomes indispensable to those who depend on it even as it stifles society. And 3) It is inevitably used by government to suppress knowledge of scandals, injustices, and high-level crime.

News, “Atheist philosopher strongly supports online political censorship” at Mind Matters News (August 23, 2022)

Takehome: Ironically, most Big Social Media are domiciled in the United States to gain the freedom of speech that they increasingly deny to others.

You may also wish to read: Why misinformation comes from the top as well as the bottom. At Big Think, Cameron English asks us to look at the incentives for academic scientists to publish questionable research that gains widespread attention. When the incentive structure in science rewards clickbait claims, Establishment wars on “Misinformation” become a form of corruption. In the real world, there is no pristine source of Correct Information. Nor is there any reason to believe that those who insist that their motive is to prevent Misinformation are entirely motivated only by a sincere devotion to truth. Many may also be protecting an organization, philosophy, or private interest, whether or not they recognize the fact.

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Evolution Symposium 2023 June 21-25, 2023 in Albuquerque, NM, USA

From the organizers: “The SSE Council invites proposals for one sponsored symposium at the meeting that highlights new topics, provides new perspectives, or generates new syntheses. This symposia will consist of six half-hour talks.”

This was the last symposium:

=======

2022 Sponsored Symposium
Evolution in the tropics: 70 years since Dobzhansky (Oscar Vargas, Kathleen Kay)

Tropical diversity has long fascinated biologists, but most research to-date has addressed the ecological mechanisms maintaining diversity rather than evolutionary mechanisms generating diversity. The last review of Dobzhansky’s biotic selection hypothesis from an evolutionary perspective is now a decade old. This symposium seeks to synthesize the evolutionary history and importance of biotic and abiotic selective factors to diversification in the tropics, and to set the stage for advancing the field. Our symposium encompasses several sub-disciplines, including (but not restricted to) ecology, phylogenetics, and biogeography, and selected speakers have varied taxonomic foci, including a broad range of plants and animals.

Speakers:

Kathleen Kay (University of California Santa Cruz) Dobzhansky, Janzen, and speciation research in the tropics
Jonathan Rolland (University of British Columbia) Macroevolutionary approaches and the construction of the latitudinal diversity gradient
Oscar Vargas (University of California Santa Cruz) Testing hypotheses for neotropical plant diversification using comparative methods
Kimberly Sheldon (University of Tennessee) Janzen’s mountain passes and diversification in the tropics
Michael Harvey (University of Tennessee, Knoxville) Standing species richness shapes the tempo and mode of avian speciation across the Neotropics
Phyllis Coley (University of Utah) The role of plant-herbivore interactions in the maintenance and origin of tropical tree diversity

=====

If you think you have a topic for them, the organizers stress diversity but here’s what that means:

SSE Council seriously considers the diversity of participants as a criterion for symposium funding. Symposium organizers are expected to take into account gender, seniority, nationality, and other axes of diversity traditionally underrepresented in Society symposia, and to describe their efforts in the proposal. SSE will accept requests for additional funds for dependent care costs if this would allow a speaker to accept an invitation to speak in a sponsored symposium.

No, we didn’t notice anything about diverse viewpoints either. Must be a typo.

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At Mind Matters News: News from the search for extraterrestrial life 2

A new ocean planet, a planet with carbon dioxide, and new discoveries about life chances on Mars:

What may be an ocean planet has been discovered in the region of the Constellation Draco… Also, the James Webb Space Telescope has found “unequivocal” evidence of carbon dioxide on a Jupiter-like gas giant at 700 light years away…

The Webb’s ability to identify a planet’s specific chemical composition at that distance means researchers can focus on those exoplanets among the thousands spotted that are most likely to host carbon-based life…

Meanwhile, with NASA’s Artemis 1 Moon mission nearing blastoff, some analysts point to the far side of the Moon as a good place to base a radio telescope: that would see even further than the Webb

News, “News from the search for extraterrestrial life 2” at Mind Matters News (August 27, 2022)

Progress? We now need the Artemis Accords to divvy up nations’ rights re Moon exploration — and the far side might host a telescope better than the Webb.

Takehome: One reason for hope for finding life elsewhere in the universe is that the universe appears to be fine-tuned for life. What the universe won’t do is tell us where the life is.

You may also wish to read: News from the search for extraterrestrial life I: Super-Earths that might have life, choosing life forms to take to Mars, and self-replicating robots… NASA is looking at developing a swarm of tiny robots to look for extraterrestrial life on oceanic worlds like Europa or Enceladus. (August 20, 2022)

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At Phys.org: Reconstructing ice age diets reveals unraveling web of life

Research published this week in Science offers the clearest picture yet of the reverberating consequences of land mammal declines on food webs over the past 130,000 years. It’s not a pretty picture.

“While about 6% of land mammals have gone extinct in that time, we estimate that more than 50% of mammal food web links have disappeared,” said ecologist Evan Fricke, lead author of the study. “And the mammals most likely to decline, both in the past and now, are key for mammal food web complexity.”

Illustration depicting all mammal species that would inhabit Southern California (top), New South Wales, Australia, (middle) and central Colombia (left) today if not for human-linked range reductions and extinctions from the Late Pleistocene to present. Credit: Oscar Sanisidro/University of Alcalá

A food web contains all of the links between predators and their prey in a geographic area. Complex food webs are important for regulating populations in ways that allow more species to coexist, supporting ecosystem biodiversity and stability. But animal declines can degrade this complexity, undermining ecosystem resilience.

Although declines of mammals are a well-documented feature of the biodiversity crisis—with many mammals now extinct or persisting in a small portion of their historic geographic ranges—it hasn’t been clear how much those losses have degraded the world’s food webs.

To understand what has been lost from food webs linking land mammals, Fricke led a team of scientists from the United States, Denmark, the United Kingdom and Spain in using the latest techniques from machine learning to determine “who ate who” from 130,000 years ago to today. Fricke conducted the research during a faculty fellowship at Rice University and is currently a research scientist at the Massachusetts Institute of Technology.

Using data on modern-day observations of predator-prey interactions, Fricke and colleagues trained their machine learning algorithm to recognize how the traits of species influenced the likelihood that one species would prey on another. Once trained, the model could predict predator-prey interactions among pairs of species that haven’t been directly observed.

“This approach can tell us who eats whom today with 90% accuracy,” said Rice ecologist Lydia Beaudrot, the study’s senior author. “That is better than previous approaches have been able to do, and it enabled us to model predator-prey interactions for extinct species.”

By charting change in food webs over time, the analysis revealed that food webs worldwide are collapsing because of animal declines.

“The modeling showed that land mammal food webs have degraded much more than would be expected if random species had gone extinct,” Fricke said. “Rather than resilience under extinction pressure, these results show a slow-motion food web collapse caused by selective loss of species with central food web roles.”

The study also showed all is not lost. While extinctions caused about half of the reported food web declines, the rest stemmed from contractions in the geographic ranges of existing species.

“Restoring those species to their historic ranges holds great potential to reverse these declines,” Fricke said.

He said efforts to recover native predator or prey species, such as the reintroduction of lynx in Colorado, European bison in Romania and fishers in Washington state, are important for restoring food web complexity.

“When an animal disappears from an ecosystem, its loss reverberates across the web of connections that link all species in that ecosystem,” Fricke said. “Our work presents new tools for measuring what’s been lost, what more we stand to lose if endangered species go extinct and the ecological complexity we can restore through species recovery.”

Full article at Phys.org.

The animal ecosystem as a whole apparently exhibits characteristics of fine-tuning and design that extends beyond the evidence for design seen within individual species.

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