Friday, 16 August 2024
More on why neanderthal Man is disinherited no more.
Fossil Friday: Human Nature of Neanderthals Supported Again
In a recent Fossil Friday article (Bechly 2024) I discussed the many lines of evidence that have accumulated in the past decade in favor of a fully human nature of Neanderthal men. As I documented with many references to the most up-to-date peer-reviewed research, we know that Neanderthals used fire, buried their dead, created stone circles and bone tools, made jewelry from eagle talons and used feathers as body decoration, made cave art with paintings and engravings, played music with bone flutes, used ochre as pigment and sophisticated fiber technology, produced flour from processed plants, dived for seafood, cooked food and self-medicated with herbal painkillers and antibiotics, and even produced glue from birch bark with a complex chemical procedure.
Hints of Compassion
Now, we can add compassion to this growing list of very human behaviors. A new study by Conde-Valverde et al. (2024) described fragments of hominin fossils from the Cova Negra cave in Spain, which have been dated by electron spin resonance (ESR)/U-series to an age of 273-146 thousand years ago. The age and the morphology clearly suggest an attribution to Neanderthals. But the truly remarkable finding was that the remains of a six-year-old child showed the typical congenital pathologies of the inner ear associated with debilitating Down syndrome. The authors suggest that this disabled child “would have required care for at least 6 years, likely necessitating other group members to assist the mother in childcare.” The press release emphasized that this “Fossil of Neanderthal child with Down’s syndrome hints at early humans’ compassion” (Reuters 2024).
It was known already that Neanderthals cared for sick and injured individuals (Hublin 2009, Noble 2010, Spikins et al. 2010, 2018, Tilley 2015, 2022, Thorpe 2016, Spikins 2022), but such behavior can also be found in some of the more intelligent and social animal species like the great apes, elephants, and whales. However, extended caregiving for a strongly disabled child is a highly non-Darwinian behavior that indeeds suggests compassion on a level only found in humans, because it is not driven by mere survival of the fittest and differential reproductive success. Elephants abandon or even kill disabled infants (Rodrigo 2011). Monkeys and apes usually neglect or reject disabled infants (Hogenboom 2015), or at best bother to care for a few weeks (Jackson 2023, Valença & Falótico 2023). There exists just a single report of maternal care for a 23-months-old disabled chimp infant with symptoms similar to Down syndrome (AFP 2015, Matsumoto et al. 2016). The compassionate caregiving of Neanderthals is clearly not intermediate between such animal behaviour and human behavior, but rather as Noble (2010) put it: Modern research “rejects the popular portrayal of Neanderthals as simple, unfeeling brutes and suggests that our closest ancient relatives may well have demonstrated a level of compassion that would put many modern humans to shame, caring for the infirm and the vulnerable for years at a time in organised groups.”
Strongly Corroboration
As I discussed in my previous article (Bechly 2024), the strong evidence for significant and common genetic admixture with modern humans, also suggests that Neanderthals and modern humans belonged to the same species. This was recently strongly corroborated by a new genetic study published in the journal Science (Li et al. 2024; also see Choi 2024b and Starr 2024), which found clear evidence for a “recurrent gene flow between Neanderthals and modern humans over the past 200,000 years”, suggesting a decreasing Neanderthal population that “was ultimately being absorbed into the modern human gene pool” as already suggested by a previous study (Stringer & Crété 2022). This definitely goes far beyond just some rare instances of admixture. Instead, it confirms a shared gene pool of different subpopulations within the same biospecies. Neanderthals were not a separate species of primitive hominins that went extinct, but were one of us and are still with us in our genes. They only vanished as a distinct group just like many other ancient subpopulations of humans, such as the Jomon people in Japan.
A Somewhat Different Result
Strangely, another new genetic study by Iasi et al. (2024), which is still in preprint stage and not yet peer-reviewed, comes to a somewhat different result and “suggests that humans interbred with Neanderthals 47,000 years ago for a period lasting 6,800 years” (Choi 2024a), but that “interbreeding that occurred at other times, such as the earlier events that impacted the Neanderthal genome, likely did not leave a detectable trace in our genome” (Choi 2024b). Looks like there is still much room for disagreement and different interpretation of the data, leading to quite different speculative scenarios.
Anyway, neither compassionate human behavior nor a shared gene pool would by itself refute a Darwinian evolution of modern humans, but such evidence certainly better resonates with the views of Darwin critics, who have always championed the view that there is only one humankind and that it is unique and distinct from the animal kingdom. Neanderthals and other ancient representatives of our genus Homo are not “stepping stones” on the way from bacteria to Beethoven, but just examples of human diversity in space and time.
References
AFP 2015. Japan researchers find chimps caring for disabled infant. Phys.org November 11, 2015. https://phys.org/news/2015-11-japan-chimps-disabled-infant.html
Bechly G 2024. Fossil Friday: New Evidence for the Human Nature of Neanderthals. Evolution News February 2, 2024. https://evolutionnews.org/2024/02/fossil-friday-new-evidence-for-the-human-nature-of-neanderthals/
Choi C 2024a. Neanderthals and humans interbred 47,000 years ago for nearly 7,000 years, research suggests. LiveScience June 7, 2024. https://www.livescience.com/archaeology/neanderthals-and-humans-interbred-47000-years-ago-for-nearly-7000-years-research-suggests
Choi C 2024b. Neanderthals didn’t truly go extinct, but were rather absorbed into the modern human population, DNA study suggests. LiveScience July 11, 2024. https://www.livescience.com/health/genetics/neanderthals-didnt-truly-go-extinct-but-were-rather-absorbed-into-the-modern-human-population-dna-study-suggests
Conde-Valverde M, Quirós-Sánchez A, Diez-Valero J, Mata-Castro N, García-Fernández A, Quam R, Carretero JM, García-González R, Rodríguez L, Sánchez-Andrés Á, Arsuaga JL, Martínez I & Villaverde V 2024. The child who lived: Down syndrome among Neanderthals? Science Advances 10(26):eadn9310, 1–10. DOI: https://doi.org/10.1126/sciadv.adn9310
Iasi LNM, Chintalapati M, Skov L, Bossoms Meta A, Hajdinjak M, Peter BM & Moorjani P 2024. Neandertal ancestry through time: Insights from genomes of ancient and present-day humans. bioRxiv May 13, 2024. DOI: https://doi.org/10.1101/2024.05.13.593955
Hogenboom M 2015. The wild chimpanzee who cared for her child with disability. Projeto GAP November 17, 2015. https://www.projetogap.org/en/news/the-wild-chimpanzee-who-cared-for-her-child-with-disability/
Hublin J 2009. The prehistory of compassion. PNAS 106(16), 6429–6430. DOI: https://doi.org/10.1073/pnas.0902614106
Jackson J 2023. Compassionate disabled infant care from a wild capuchin monkey mother. Phys.org March 7, 2023. https://phys.org/news/2023-03-compassionate-disabled-infant-wild-capuchin.html
Li L, Comi TJ, Bierman RF & Akey JM 2024. Recurrent gene flow between Neanderthals and modern humans over the past 200,000 years. Science 385(6705), 1–10. DOI: https://doi.org/10.1126/science.adi1768
Matsumoto T, Itoh N, Inoue S & Nakamura M 2016. An observation of a severely disabled infant chimpanzee in the wild and her interactions with her mother. Primates 57, 3–7. DOI: https://doi.org/10.1007/s10329-015-0499-6
Noble C 2010. My bright idea: Neanderthals could show compassion. The Guardian October 10, 2010. https://www.theguardian.com/technology/2010/oct/10/bright-idea-neanderthals-evolution
Reuters 2024. Fossil of Neanderthal child with Down’s syndrome hints at early humans’ compassion. The Guardian June 26, 2024. https://www.theguardian.com/science/article/2024/jun/26/fossil-of-neanderthal-child-with-downs-syndrome-hints-at-early-humans-compassion
Rodrigo M 2011. Handicapped baby jumbo left bleeding and abandoned in paddy field. Sunday Times May 1, 2011. https://www.sundaytimes.lk/110501/News/nws_28.html
Spikins P 2022. Material evidence: Caring for adult vulnerabilities. pp. 71–127 in: Hidden Depths: The Origins of Human Connection. White Rose University Press, New York (NY). DOI: https://doi.org/10.22599/HiddenDepths.c
Spikins P, Rutherford H & Needham A 2010. The Prehistory of Compassion. Blurb, 106 pp. https://www.blurb.com/b/1628917-the-prehistory-of-compassion
Spikins P, Needham A, Tilley L & Hitchens G 2018. Calculated or caring? Neanderthal healthcare in social context. World Archaeology 50, 384–403. DOI: https://doi.org/10.1080/00438243.2018.1433060
Starr M 2024. Humans And Neanderthals Had a Longer, More Intertwined Relationship Than We Thought. ScienceAlert July 12, 2024. https://www.sciencealert.com/humans-and-neanderthals-had-a-longer-more-intertwined-relationship-than-we-thought
Stringer C & Crété L 2022. Mapping Interactions of H. neanderthalensis and Homo sapiens from the Fossil and Genetic Records. PaleoAnthropology 2, 401–412. DOI: https://doi.org/10.48738/2022.iss2.130
Thorpe N 2016. The Palaeolithic Compassion debate – Alternative Projections of Modern-Day Disability into the Distant Past. Chapter 6, pp. 93–110 in: Powell L, Southwell-Wright W & Gowland R (eds). Care in the Past: Archaeological and Interdisciplinary Perspectives. Oxbow Books, Oxford (UK), 208 pp. https://www.jstor.org/stable/j.ctt1kw290q.11
Tilley L 2015. Setting the Scene for a Bioarchaeology of Care. pp. 13–64 in: Theory and Practice in the Bioarchaeology of Care. Springer, Cham, xvii+319 pp. DOI: https://doi.org/10.1007/978-3-319-18860-7_2
Tilley L 2022. Disability and Care in the Bioarchaeological Record. Meeting the Challenges of Being Human. pp. 457–481 in: Grauer AL (ed.). The Routledge Handbook of Paleopathology. Routledge, London (UK), 692 pp. https://www.taylorfrancis.com/chapters/edit/10.4324/9781003130994-28/disability-care-bioarchaeological-record-lorna-tilley
Valença T & Falótico T 2023. Life and death of a disabled wild capuchin monkey infant. Primates 64, 207–213. DOI: https://doi.org/10.1007/s10329-023-01052-1
The Bishop's Mitre: a brief history.
Mitre, liturgical headdress worn by Roman Catholic bishops (including cardinals, archbishops, and popes) and abbots and some Anglican and Lutheran bishops. It has two shield-shaped stiffened halves that face the front and back. Two fringed streamers, known as lappets, hang from the back. It developed from the papal tiara and came into use in the 11th century. The mitre is worn over a zucchetto, a silk or polyester skullcap. See also religious dress.
Three types of mitres are worn in the Roman Catholic Church. The simplex is made of undecorated white linen or silk and is worn at funerals, on Good Friday, and for some other services, such as Candlemas. The auriphrygiata is made of plain gold cloth or white silk with gold or silver embroidered bands and is worn during penitential seasons (Advent and Lent) and at some other times. The pretiosa is decorated with precious stones and gold and worn on Sundays and feast days, as well as for ceremonies such as the election of a pope, the consecration of a bishop, or the canonization of a saint.
The Greek mitra worn by bishops and some Russian clergy in the Eastern churches is similar to a closed crown with a cross on top.
Yet more on why there is truly no place like home.
Study: Geological Habitability Parameters Imply Earth is Special and Advanced Life Extremely Rare
Looking forward to the August 27 release of the new edition of The Privileged Planet, which you can pre-order now, we’ve been considering issues of habitability — on Mars (here and here), and on the moons Enceladus and Titan. Now comes a new paper in Scientific Reports, “The importance of continents, oceans and plate tectonics for the evolution of complex life: implications for finding extraterrestrial civilizations.” It argues that extraterrestrial “advanced communicative civilizations” (or ACCs) must be extremely rare in the universe. Their logic is simple: ACCs would require planets with continents, oceans, and plate tectonics, but these major geological features of Earth are likely to be very rare elsewhere. If these features are required for ACCs, and if they are rare, then such advanced civilizations must also be very rare.
An excellent article at Nautilus, “The Odds That Aliens Exist Just Got Worse,” explains the paper’s basic findings: “The likelihood that other technologically sophisticated societies exist is smaller than previously thought, because basic amenities we take for granted on Earth — continents, oceans, and plate tectonics — are cosmically rare.” But if we take these findings out of the context of current obsessions over aliens, then the implication, of course, is simply that Earth is very privileged because the presence of continents, oceans, and plate tectonics on our planet is extremely rare.
Unknowns of the Drake Equation
As a geologist, what I find most fascinating about this Scientific Reports article is that it adds new geological factors to the Drake equation. That is the famous equation that is used to roughly calculate the number of technologically advanced extraterrestrial civilizations in our galaxy. The Nautilus article notes that the values of some factors in the classical formulation of the Drake equation are very difficult to estimate, particularly:
the fraction of potentially habitable planets on which life likely has emerged (a variable that’s completely unconstrained, since only one case — ours — is known); the fraction of those planets on which intelligent life has developed (a criterion that often elicits dark humor about whether human life qualifies); the fraction of that fraction that have sent signals into deep space (again, just one known example, out-going calls only); and the length of time those civilizations have been sending such signals (to be determined).
Some argue that even the low ends of reasonable estimated ranges for these factors imply that ET life should be sending telecommunications to us Earthlings. So why aren’t we getting any signals? This absence of ET life communicating with us is known as the “Fermi Paradox.”
How to Resolve the Fermi Paradox?
There are many possible ways to understand why we aren’t hearing from ET life — not the least of which is that, as the best evidence suggests, life is extremely unlikely to arise via natural chemical means. But the Nautilus article explains that the study tried to resolve the paradox by arguing that very few planets have the requisite geological factors needed for advanced life to arise:
Bringing a geologic perspective to the problem, Stern and Gerya propose to resolve the paradox by adding two more factors to the already unwieldy Drake equation: the fraction of habitable planets with distinct continents and oceans; and the fraction of those planets with a plate tectonic system that has operated for at least 500 million years. The values of these terms are very small, they argue, because the development of distinct landmasses and water bodies, and the tectonic habit of crustal recycling — characteristics of Earth that we take for granted — are unlikely outcomes in the evolution of rocky planets.
With these new factors, the number of advanced civilizations in our galaxy that might communicate with us falls to … almost zero.
The technical paper explains that a planet where ACCs evolve requires ocean basins, continental dry land, and plate tectonics: “Although primitive life must evolve in the sea, advanced communicative civilizations must evolve on dry land.” In light of these requirements, it proposes geological terms for resolving the Fermi Paradox:
We resolve the Fermi Paradox (1) by adding two additional terms to the Drake Equation: foc (the fraction of habitable exoplanets with significant continents and oceans) and fpt (the fraction of habitable exoplanets with significant continents and oceans that have had plate tectonics operating for at least 0.5 Ga); and (2) by demonstrating that the product of foc and fpt is very small (< 0.00003–0.002).
Note the value at the end: “< 0.00003–0.002.” If you add a factor with that value to the Drake equation, it suggests that ACC life elsewhere in the galaxy is extremely rare — if it exists at all.
Plate Tectonics Necessary for Life
There are multiple reasons why plate tectonics is necessary for life — something I spoke about in my talk at Discovery Institute’s 2022 Dallas Conference on Science and Faith.
Thus, I wholeheartedly agree with the Nautilus article when it states:
Most geologists will agree with Stern’s and Gerya’s argument that plate tectonics should be included as a criterion for long-term planetary habitability. Earth’s tectonic system allows the planet’s atmosphere and hydrosphere to remain in communication with its interior, in a remarkable, self-perpetuating cycle. Subducted ocean crust — seafloor that slips down into Earth’s interior — carries water back into the mantle, and at shallow depths, this water lowers the melting temperature of mantle rock, giving rise to unusual magmas that create the continental crust — what we surface dwellers live on — which is rich in rare elements, like phosphorus, that are critical to life.
At greater depths, subducted water acts to decrease the viscosity of the mantle, allowing it to churn, or convect, more vigorously — which in turn drives plate motion. When the Earth’s mantle exports heat via convection, it encourages the liquid iron outer core to convect as well, and this generates Earth’s protective magnetic field, which shields the surface environment from harmful cosmic radiation. Without plate tectonics, continents would quickly be eroded to sea level. But tectonic collisions continuously rejuvenate Earth’s topography, providing rivers with more energy to transport nutrient-rich sediments to shallow marine environments. In other words, plate tectonics is entangled with all the phenomena that support life on Earth.
So plate tectonics is vital for generating our magnetic field (necessary for life), maintaining the presence of life-necessary elements in the oceans, and creating both continents and oceans (which, if you haven’t noticed, are also vital for advanced life). This is all very reasonable, as is the study’s conclusion that plate tectonics is probably very rare on planets in the universe.
One reason for this is that all of the other rocky planets in our solar system have something called “stagnant lid” tectonics. That’s where the lithosphere of a planet is composed of a single plate and only vertical tectonic movement occurs due to upwelling from the mantle, but not horizontal plate movement. Earth is the only known planet to have horizontal plate tectonics movement, suggesting it is rare:
How Old Is Plate Tectonics on Earth?
One thing that is likely to get some pushback is the study’s claim that modern-style plate tectonics on Earth did not commence until the Neoproterozoic, which lasted from about 1 billion years ago until the beginning of the Cambrian period (about 540 million years ago). Many geologists, including many who work in paleomagnetism (the field of my PhD research), would argue that plate tectonics began very early in Earth’s history. That’s because we see evidence of continents on the move going all the way back into the Archean. But this controversy should not affect the paper’s basic claim. Here’s why:
The value of their fpt factor, added to the Drake equation, assumes that plate tectonics has only been operating on Earth for about 0.5 Ga (Ga = gigaannum, or a billion years). If plate tectonics has been operating for longer than that, it would presumably make Earth even more special, because plate tectonics would be longer lasting. In other words, in estimating the specialness of Earth, the paper’s calculations are conservative. In any case, however long plate tectonics has been operating on our planet, it seems that any other planets with plate tectonics, continents, and oceans are rare, and very special indeed.
Our Lord and Savior is a biblicist.
John ch.17:17KJV"Sanctify them through thy truth: thy word is truth."
John ch.5:39KJV"Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."
John Ch.5:45KJV"“But do not think I will accuse you before the Father. Your accuser is Moses, on whom your hopes are set."
Luke Ch.16:29-31KJV"Abraham saith unto him, They have Moses and the prophets; let them hear them.And he said, Nay, father Abraham: but if one went unto them from the dead, they will repent. 31And he said unto him, If they hear not Moses and the prophets, neither will they be persuaded, though one rose from the dead."
Luke Ch.24:32KJV"And they said one to another, Did not our heart burn within us, while he talked with us by the way, and while he opened to us the scriptures?"
The true Spirit of JEHOVAH causes reverence for and clear understanding of JEHOVAH'S Word the Holy Bible,any Spirit exalting tradition over JEHOVAH'S Word or promoting irrational exegesis of same is of a different source.
Thursday, 15 August 2024
Yet another neoDarwinian looking for frenemies?
James Shapiro: Intelligent Design “Has a Valid Point with Regard to the … Limits of Neo-Darwinism”
Earlier this year, the National Association of Scholars recently published an interesting issue of their journal Academic Questions. It’s on a special theme, “The State of Evolution,” and it includes many articles that are worth reading. One article, by University of Chicago biologist James Shapiro, is titled, “Evolution Is Neither Random Accidents nor Divine Intervention: Biological Action Changes Genomes.” Shapiro provides a very nice review of various functions that have been discovered for transposable elements — a type of repetitive DNA that was once labeled “junk,” but which we now know is “needed for various aspects of genome function.” He writes:
[R]epetitive DNA was labelled as “junk DNA,” “selfish DNA,” or “selfish genetic elements.” Richard Dawkins famously erected a widely popular philosophy of evolution on the basis of “The Selfish Gene” (1976).
Today, we recognize that most of this repetitive DNA is made up of transposable elements and other repeats needed for various aspects of genome function, especially developmental regulatory networks controlling cellular differentiation. The repeats help guide the origin of cell lines that comprise distinctive tissues, say bone tissue versus nervous tissue. Both have the same DNA, yet each cell type expresses the genome in distinctive ways controlled by different DNA repeats.
A Curious Comment
I highly recommend the paper. It also includes a curious comment about intelligent design:
Support for evolution guided by divine intervention has a toehold in the quasi-scientific Intelligent Design (ID) movement, initiated by Michael Behe (“Darwin’s Black Box: The Biochemical Challenge to Evolution,” 1996) and carried on by members of the Discovery Institute and other creationist think tanks. The basic argument that ID theorists make is that natural selection of random hereditary changes cannot produce genomes capable of expressing all the intricate networked adaptations modern molecular biology has revealed to operate in living organisms. This conundrum is, in Behe’s words, “irreducible complexity.” Hence, the ID theorists posit a need for divine intervention.
The ID argument has a valid point with regard to the explanatory limits of neo-Darwinism, still widely regarded as the only legitimate scientific explanation of evolution. ID falls down by assuming (as do mainstream evolutionists) that genome change occurs from outside the boundaries of life itself. Within the scientific community, there is agreement that the hereditary variation necessary for evolutionary change occurs by natural means. But significant difference exists between scientists about what constitutes “natural means.”
Shapiro is a great biologist who has offered many keen insights into the nature of genomic functioning. He’s clearly not an ID proponent and that is fine. I would disagree with his characterization of ID as a negative argument against evolution in favor of “divine intervention.”
The Struggles of Neo-Darwinism
But he’s absolutely correct to note that neo-Darwinism struggles to account for the “intricate networked adaptations modern molecular biology has revealed to operate in living organisms.” And I appreciate his recognition that ID got this one right. Shapiro thinks that natural genetic engineering can account for many of this intricate complexity — and we in the ID movement are interested in seeing how far these mechanisms of pre-programmed evolution can take us.
For my part, I think they might be useful for fine-tuning pre-existing functions — and may be involved in what Emily Reeves recently wrote about as “continuous environmental tracking.” But I’m skeptical that Dr. Shapiro’s model can account for much of the basic complexity of life. For the moment, I’m content to be grateful to him as a non-ID scientist who recognizes something ID has gotten right.
Wednesday, 14 August 2024
Monday, 12 August 2024
Madness in the method?
An Object Lesson in How Not to Do Science
British science writer Philip Ball, looks back on the mapping of the human genome and what has followed from it. Writing at Aeon, he senses a need for change in the way we look at Earth’s life forms. But he doesn’t seem to want too much change.
As the author of How Life Works (University of Chicago Press 2023) and Beautiful Experiments (University of Chicago Press 2023), Ball admits,
Talk of a genetic blueprint, of selfish genes, of instruction books and digital codes gave us a narrative we could grasp. Even though we now know this to be at best a partial and at worst a misleading picture, it’s likely to remain in place until there is something better on offer.
PHILIP BALL, “WE ARE NOT MACHINES,” AEON, JULY 12, 2024
What Most of Us Learned in School Was Faulty
He is aware of the limitations of that point of view but sees it as part of the inherent conservatism of science. Still, he looks for another, more accurate story. Thus, he reveals — surprising many of us perhaps — that most of what we learn in school gives rise to misconceptions. For example,
Only around 1-2 percent of the entire human genome actually consists of protein-coding genes. The remainder was long thought to be mostly junk: meaningless sequences accumulated over the course of evolution. But at least some of that non-coding genome is now known to be involved in regulating genes: altering, activating or suppressing their transcription into RNA and translation into proteins. Many disease-linked regions are in these regulatory sequences, where mutations don’t change the proteins themselves but, rather, the rate or chance of them being made at all. So, to understand how life really works at the genomic level, we need to understand gene regulation. And that, as we’ll see, is not just eye-wateringly complicated but not at all what we have learnt to expect from the conventional molecular biology of the past 50 years.
BALL, “WE ARE NOT MACHINES”
And not all genes even encode proteins. Also RNA seems to have some functions other than serving as a messenger for making proteins.
Ball grasps the strangeness of the fact that the public still hears the same Central Dogma story about the human genome as it did in the 1960s and thus has little idea how complex it all really is — and how poorly understood:
Thetemptation is to throw up one’s hands and conclude that, for humans at least, how life works surpasses all understanding. Some biologists have implied as much, suggesting that we might never truly understand life mechanistically, but will just have to rely on data mining with black-box AI to make predictions about what will lead to what.
BALL, “WE ARE NOT MACHINES”
Leaving it all to the computer does not, of course, seem like an obviously sound idea. And Ball goes on to say something quite profound:
… it’s not hard to see why, the more complex the organism, the fuzzier its molecular mechanisms have to be. A huge machine that works only if all its countless components interlock in precisely coordinated ways is far too fragile —especially if those parts are, like molecules, constantly moving about randomly in a warm, wet environment. By the same token, if life relied on the accurate readout of innumerable genomic instructions in exactly the right order, it would be far too vulnerable to errors. It’s for these reasons that we are not machines — not, that is, like any machine humans have ever built. It’s a far better and more robust solution to find principles that work over many hierarchical levels, with the operation at one level being not too sensitive to the fine details of the levels below. Gene regulation by rather loosely defined condensates rather than by specific molecular switches, say, means that it can still work without every molecule having to be present and correct.
BALL, “WE ARE NOT MACHINES”
Yes But how is this astonishing feat accomplished?
Evolution has, to speak anthropomorphically, evidently ‘designed’ our molecules to work in this fuzzy way. In contrast to the lock-and-key principle by which protein enzymes were long thought to recognise and transform their target molecules, some of the most important proteins in our cells, including many transcription factors, have shapes that are only loosely defined, enabling them to stick to others without being too choosy about it. And those little regulatory RNAs are generally too small to carry enough information for their unions to be very selective; they too work collectively, arriving at a decision, as it were, by committee.
BALL, “WE ARE NOT MACHINES”
The Unthinkable Thought
In short, the life we know can only be envisioned by appealing to intelligent design, while pretending not to.
Ball goes on to address the question of why the problems with the current picture are not better known: “Having long interacted with scientists of all persuasions, I’ve noticed a contrast between how physicists and biologists receive and communicate new ideas.”
Oh for heaven’s sakes, why can’t he just come right out and admit the reality? There is no reasonable hope that Darwinian evolution could have done all that is required in the time allowed — or in any amount of time. And, given how much has been invested in Darwinism over the years, no one wants to be first to stick a trowel in that beehive. That’s why.
Ball goes on to discuss the ENCODE project, which found that supposedly “junk DNA” often does have a biological function:
Some biologists responded by saying, in effect: ‘No no no, nothing to see here – our existing understanding is just fine.’ (This was mild stuff compared with the furious reaction the ENCODE paper itself elicited from some biologists, who accused the team of evolutionary heresy on a par with intelligent design.) Others said that, even if biology was indeed more complicated that we’d thought, what was to be gained by telling the public that? In other words: don’t upset the status quo.
BALL, “WE ARE NOT MACHINES”
Investment in a Belief System
That’s not about science; it’s about investment in a belief system. When Ball, admirably, checked the story out in the Systems Biology department at Harvard one summer, he learned that the whole thing was “much worse than that!” He now thinks that biologists are too invested in the Human Genome Project approach and that we need “new narratives” in biology. But then he also argues,
It has also become much harder in recent years for scientists to admit to gaps in knowledge and understanding, which will be exploited by everyone ranging from creationists to climate-change deniers to anti-vaxxers as evidence that we shouldn’t believe a word they say.
BALL, “WE ARE NOT MACHINES”
In short, the story the public is told is contrary to evidence — and to reason, actually — but scientists have to keep telling it because otherwise the wrong people might benefit. That is practically an object lesson in how not to do science. But Ball has thought and said as much as he can while remaining safe.
Sunday, 11 August 2024
Saturday, 10 August 2024
Darwinism can't spin straw into gold?
How “Junk” DNA Got Its Function: Evolutionary Tales Fail to Convince
Recently I wrote about various functions that have been identified for “junk” DNA. Of course, many functions have been discovered for the supposed “junk,” but these form a special case where diseases played a role. How are they being identified? It’s because when those functions go wrong, diseases result. Most evolutionists aren’t bothered by such findings of individual functions for junk DNA. They just claim that occasionally junk gets co-opted to do something useful, or even vital to our health. They offer evolutionary accounts of how the junk got its function — but those accounts often appear highly unlikely. Here are a couple of examples.
Did junk DNA cause humans to lose their tails.
Earlier this year there was a flurry of stories about how “junk DNA” may explain why humans don’t have tails. As the story goes, a transposable element called an Alu sequence got randomly inserted into a regulatory intron of a gene called TBXT, which is involved in the early development of the neural tube (which later becomes the spinal column). An evolutionary story ensues, outlined at Study Finds:
The researchers identified a specific genetic alteration — an inserted piece of DNA — present in humans and apes but absent in monkeys. This insertion, located in a gene known as TBXT, is believed to play a critical role in the development, or rather the absence, of tails in humans.
Technical paper in Nature elaborates on the story.
We demonstrate that this Alu element — inserted into an intron of the TBXT gene — pairs with a neighbouring ancestral Alu element encoded in the reverse genomic orientation and leads to a hominoid-specific alternative splicing event. … the exon-skipped transcript is sufficient to induce a tail-loss phenotype.
This particular Alu element is precisely located to allow the gene variant to arise — as the study’s lead author tweeted:
So it takes TWO to make an impact! The unique alignment of a pair of Alu elements is crucial; without it, neither element would have significance.
One scientist called this event a “strange evolutionary quirk.” Strange indeed. The story is an evolutionary framing of the study’s findings, and it’s cool research, but what is the raw data here? The raw data is simply a genetic difference that has been identified between hominoids and monkeys, and the difference is likely part of what builds the tail-less hominoid body plan. The evolutionary story thus makes a common mistake: it confuses the identification of how some aspect of human development works with an evolutionary explanation of how that aspect of the body plan originated.
Moreover, if this were a true evolutionary story, it’s doubtful that the change alone really would be “sufficient” to cause an advantageous change leading to tail-loss. The technical paper suggests other mutations were probably needed:
[E]ven if the AluY insertion substantially influenced tail-loss evolution in hominoids, additional genetic changes may have acted to stabilize the no-tail phenotype. Such possible hominoid-specific variants in tail-development-related genes may have preexisted in the ancestral genome or occurred after the AluY insertion. Such a possible set of genetic events suggest that a change to the AluY element in modern hominoids would be unlikely to result in the reappearance of the tail.
The technical paper reports that when this gene variant is induced in mice, “mice expressing the exon-skipped Tbxt isoform develop neural tube defects.” Humans can experience this genetic defect as well, and this means that undoubtedly multiple coordinated genetic changes would have been necessary to evolve the tail-less phenotype without experiencing other disease-related problems, such as neural tube defects. The paper continues:
We suggest, however, that the selective advantage must have been strong because the loss of the tail may have included an evolutionary trade-off of neural tube defects, as demonstrated by the presence of neural-tube-closure defects in mice expressing the TbxtΔexon6 transcript.
The language there is interesting: because of the highly deleterious neural-tube closure defects associated with this gene variant in mice, the only way this could change could have been selected was if it provided a “strong” selective advantage offsetting the greatly increased likelihood of disease — an “evolutionary trade-off.” It’s hard to imagine a scenario where such a greatly increased risk of disease would somehow be tolerable simply in exchange for losing your tail. Multiple other coordinated mutations would seemingly be needed to avoid serious birth defects. But when multiple mutations are needed to avoid such deleterious defects, that is highly unlikely under blind evolution and speaks to the need for foresight, planning, and intelligence.
Interestingly, a co-author of the study noted in Scientific American that this evidence shows that Alu sequences “aren’t just cluttering the genome” and are “important”
AluY was an unexpected piece of the puzzle because millions of such elements are present in our cells — and for a long time they were referred to as “junk DNA” because researchers believed they were littering the human genome at random and seemingly with no purpose. “It shows that these elements aren’t just cluttering the genome,” Yanai says. “They’re doing something important.”
Taken as a whole, this tale provides more evidence that when you mess with the “junk,” you mess with its function, and problems arise. And evolutionary stories of how the junk got its function just aren’t adding up. If this story were true, then multiple mutations would be necessary in order to avoid very severe developmental defects, something that points to planning and design, not blind evolution.
Does Junk Give Us Big Brains?
Here’s another example of a questionable evolutionary story about how junk DNA got its function: An article at Live Science says “Humans’ big-brain genes may have come from ‘junk DNA.’” They report, “the genes that enabled human brains to grow large lobes and complex information networks may have originally emerged from junk DNA.” Once again, identifying how things work is not an explanation for how they evolved. The original paper in Nature Ecology & Evolution states:
Human de novo genes can originate from neutral long non-coding RNA (lncRNA) loci and are evolutionarily significant in general, yet how and why this all-or-nothing transition to functionality happens remains unclear.
Don’t miss the words “all-or-nothing transition” — this suggests that transforming the “junk” into functional genes would have required many coordinated changes. Sure, these genes are important for human brain development, but is such a set of coordinated changes to transform “junk” into crucial genes likely to occur by blind evolution? It seems not.
Whatever the answer, this much is clear: junk DNA performs many important functions, and when evolutionists try to interpret the origins of those functions from within their paradigm, the results often fail to stand up to scrutiny.
Friday, 9 August 2024
An air strike against Darwinian gradualism?
Fossil Friday: The Carboniferous Explosion of Winged Insects
Among the numerous abrupt appearances of new animal body plans in the history of life (Bechly 2024) there are also striking examples from my own field of research, which is the fossil history of winged insects (Pterygota), the most diverse group of organisms which includes more described species than all other multicellular life combined (Grimaldi & Engel 2005). Therefore, this Fossil Friday features the holotype of Fouquea superba, a winged insect of the order Palaeodictyoptera from the Upper Carboniferous of Commentry in France.
There have been three key innovations in the history of insects that contributed to the great success of this group. Those include the origin of wings and flight, the origin of foldable wings (Neoptera), and the origin of complete metamorphosis (Holometabola) (Nicholson et al. 2014). It is truly astonishing that all these three innovations appeared abruptly and very early among the oldest winged insects from the Carboniferous, which also exhibited a great diversity and disparity from the very beginning. I call this the Carboniferous Insect Explosion.
In the Pennsylvanian (Upper Carboniferous) subperiod between 323-299 million years ago, when the world was forming a single supercontinent Pangaea dominated by vast tropical swamp forests, this large diversity of different winged insect groups appeared suddenly without any known transitional forms in the older Mississippian (Lower Carboniferous) or Devonian strata (Strahler 1999, Labandeira 2005, Grimaldi & Engel 2005, Knecht et al. 2011, Nicholson et al. 2015, Wang et al. 2016, Bechly 2023a). According to leading experts, “an insect equivalent of an Archaeopteryx remains elusive” (Grimaldi & Engel 2005: 160).
The early fossil record of Carboniferous winged insects does not only include giant palaeopteran insects like the extinct palaeodictyopterids, mayflies, and dragonflies, or “primitive” neopteran insect orders like stoneflies, roaches, and orthopterans, but also thrips, bugs, and even advanced holometabolans like wasps, beetles, and scorpionflies, often with “a high degree of specialization early in the evolution of insects” (Garwood & Sutton 2010). Here is a brief and incomplete list of the large diversity of early winged insect groups in the Carboniferous with their oldest known representatives (also see Nel et al. 2013: fig. 3:
Palaeodictyopterids: Delitzschala (Germany, 323 mya)
Mayflies (Ephemeroptera): Triplosoba (France, 303-299 mya)
Dragonflies / Griffenflies (Odonatoptera): Eugeropteron and Geropteron (Argentina, 325-324 mya?)
Stoneflies (Plecoptera): Gulou (China, 318-314 mya)
Roaches (Dictyoptera): Kemperala (Germany, 318 mya) and Qilianiblatta (China, 318-314 mya)
Orthopterans: Archaeorthoptera (Czech Rep., 324 mya)
Thrips (Thysanoptera): Westphalothripides (France, 314-307 mya)
Plant lice (Psocodea): Westphalopsocus (France, 314-307 mya)
Bugs (Hemiptera): Protoprosbole (Belgium, 316 mya) and Aviorrhyncha (France, 314-307 mya)
Holometabolan larvae: Metabolarva (Germany, 314-307 or 306 mya) and Srokalarva (USA, 311-307 mya)
Wasps (Hymenoptera): Avioxyela (France, 314-307 mya)
Beetles (Coleoptera): Stephanastus (France, 303-299 mya)
Neuropteroids: Srokalarva (USA, 311-307 mya) seems to be a larval neuropteroid according to Haug et al. (2015)
Scorpionflies (Mecoptera): Westphalomerope (France, 318-314 mya)
Of course, there is always considerable uncertainty concerning the identification of such fossil insects. A good example is Adiphlebia lacoana from the Pennsylvanian Mazon Creek locality in Illinois. This taxon was identified as oldest beetle by Béthoux (2009), which was accepted by Wolfe et al. (2016) and even used as fossil calibration point for the dating of beetle origins. However, the attribution of Adiphlebia to beetles was disputed by Kukalova-Peck & Beutel (2012), who instead considered it as a stem neuropterid, while it was later identified as paoliid stem dictyopteran by Kirejtshuk et al. (2014). Rasnitysn & Aristov (2013) transferred Adiphlebia to the extinct family Anthracoptilidae, which was concurred by Guan et al. (2016), who thoroughly discussed the various hypotheses for the relationship of this family (i.e., Palaeodictyopteroida, Prothorthoptera, Hypoperlida, Eoblattida (= Cnemidolestodea), stem-Mantodea, Paraneoptera, Holometabola), but ultimately supported the newer alternative of a position in Paoliida as sister group of Dictyoptera. Even though the holotype specimen of Adiphlebia is a very complete and well-preserved fossil insect, it has been attributed in the past fifteen years by different experts to almost all of the major subgroups of winged insects. Keep this in mind when you read about the next discovery of a sensational transitional fossil in the news.
Where are the Stem Pterygotes?
Given that we find so many different subgroups of modern winged insects in the Carboniferous, shouldn’t we expect to find at least some stem-pterygotes among the earliest winged insects? What and where are they? Only two candidates were suggested, namely Palaeodictyopterida and Paoliida.
Palaeodictyopteroids are an extinct group of large insects with densely veined wings and sucking-piercing mouth parts. They rank among the oldest known winged insects and were considered to be stem-pterygotes by the godfather of paleoentomology Anton Handlirsch (1906-1908), but this is no longer believed among modern experts. Their phylogenetic position is still a matter of debate, but they are generally considered to be crown group pterygotes, either more closely related to living Palaeoptera (mayflies and dragonflies) or to living Neoptera (all other winged insects, with foldable wings) (Rasnitsyn & Quicke 2002, Grimaldi & Engel 2005, Prokop & Engel 2019, Prokop et al. 2019). Prokop et al. (2019) explicitly stated that “interestingly, Palaeodictyopterida have not been recovered as sister group to all other Pterygota.” In my view, their palaeopteran wing articulation, their wing venation, their genital organs with paired penes, and larval characters with abdominal winglet-like structures (Haug et al. 2014, Prokop et al. 2022, Ross 2022), all suggest a position of palaeodictyopteroids in Palaeoptera, most likely as sister group of modern mayflies.
Paoliida are another group of early pterygote insects from the Upper Carboniferous and Permian. Based on some obsolete earlier hypotheses (Sharov 1966, Rasnitysn 1976, also see Rasnitysn & Quicke 2002), Prokop et al. (2012) considered Paoliida as “putative stem-group of winged insects”, even though Prokop & Nel (2007) had already cautioned that such a view is not supported by any synapomorphies. Consequently, no other experts accepted this hypothesis. More recent studies (Prokop et al. 2014, 2023, Legendre et al. 2015) identified Paoliida as the sister-group of roachoids (Dictyoptera) within modern Neoptera, which was also accepted and endorsed by the previous supporters of the alternative stem-pterygote hypothesis.
The only remaining potential stem-pterygote could be Carbotriplurida, which was actually suggested in a study co-authored by myself (Staniczek et al. 2014) and accepted by some later studies (e.g., Prokop et al. 2023). However, Carbotriplura from the Upper Carboniferous of the Czech Republic is just a wingless insect similar to a giant silverfish, and its position in the basal stem group of winged insects is only based on speculative scenarios and slightly broadened paranota. It basically is a fossil that roughly fits a hypothetical model (also see Haug et al. 2014, Ross 2017, 2022, Prokop et al. 2022), but not a transitional fossil in any meaningful way. It did not have anything like real mobile wings and not even anything that would be clearly identifiable as gliding or parachuting airfoils. There is no evidence or proof that it was an arboreal animal capable of gliding, and its large size rather points against this hypothesis. But including a fancy evolutionary story increased the unique selling point and impact of our paper, which I can freely admit now that I am no longer part of the Darwinian establishment and no longer under pressure from any museum PR departments to oversell results in the international competition for grants and reputation.
Devonian Proto-Wing Insects Debunked
What about alleged Devonian proto-winged insects you might have read about in text books. Don’t they prove a gradual development of wings from wingless insects prior to the Carboniferous period? No they definitely don’t do anything like that, as all known examples (Eopterum, Rhyniognatha, and Strudiella) for such alleged transitional fossils have been debunked:
Eopterum devonicum and Eopteridium striatum were described by the famous Russian paleoentomologist Rohdendorf (1961, 1970) as the oldest fossil evidence of winged insects from the Devonian of Russia. The fossils indeed resembled isolated insect wings with the characteristic wing venation. This finding made it into textbooks for decades, and was even featured in Willi Hennig’s (1969, 1981) groundbreaking work on Insect Phylogeny with detailed interpretation and naming of the wing venation. However, shortly later Rohdendorf (1972) himself already suspected that the two fossil may rather represent nothing but the isolated tail fans (uropods) of a fossil shrimp, which was strongly confirmed by the American crustaceologist Frederick Schram (1980). Bummer!
Rhyniognatha hirsti is a fragment of an arthropod head capsule from the Lower Devonian Rhynie chert in Scotland, which is about 412 million years old. The common claim that it represents the oldest insect fossil and possibly a winged insect is based on a study by Engel & Grimaldi (2004). Some experts tentatively followed their interpretation, such as Edgecombe & Legg (2013), who said that “Rhyniognatha is known from a mandible that is certainly a member of the insect clade Dicondylia (i.e. having an anterior mandibular articulation) and may even be a pterygote (Engel and Grimaldi 2004). Rhyniognatha (Fig. 15.6) extends the range of winged insects downwards from the Carboniferous.” Based on its characteristic morphology, I had always thought that Rhyniognatha rather looks like the head of a myriapod. Some colleagues from the University of Tübingen and the Natural History Museum in Stuttgart, with whom I had discussed the issue over the years fully agreed. Lo and behold, a more recent and much more thorough study by Haug & Haug (2017) suggested that Rhyniognatha was misinterpreted and indeed represents an early centipede, which was also accepted by Ross (2022).
Finally, Garrouste et al. (2012) described yet another supposed fossil evidence for a winged insect from the Late Devonian of Belgium, which they called Strudiella devonica. An accompanying comment to the original description celebrated the discovery because “a complete insect fossil from the Devonian period has long been sought” and “the finding of a candidate may improve our patchy understanding of when winged insects evolved” (Shear 2012). Otherwise, the identification of this fossil was immediately met with scepticism, because it lacked any trace of wings or even nymphal wing buds (Taylor 2012). Indeed, the fame of this fossil did not last long, because a year later a team of other distinguished scientists found that Strudiella is just a decomposing crustacean (Hörnschemeyer et al. 2013). They could hardly have been clearer when they said that “we consider it to be crucial to prevent this fossil from entering entomology textbooks as an early insect.” The original authors of course still disagreed (Garrouste et al. 2013), but most paleoentomologists no longer believe in this oldest winged insect and consider the identity of this fossil as problematic due to its poor preservation (Haug & Haug 2017).
After the debunking of Strudiella, evolutionary biologists were left empty handed with no fossil record at all of any Devonian precursors for winged insects that were postulated to exist by molecular clock studies and of course were expected by Darwinian reasoning based on the fully developed winged insects in the Lower Carboniferous (see below). Nevertheless, Darwinian scientists made grandiose claims like the following by Engel et al. (2013), which are not supported by any valid fossil evidence:
Palaeological studies have advanced significantly in the last twenty five years,particularly with a large number of reevaluations of taxa in a cladistic framework and by pushing back the timing of wing origins from the early Carboniferous into the earliest Devonian perhaps latest Silesian.
Clueless about wing origins.
The identification of putative proto-winged insects is also hampered by the more general problem that we do not even know how proto-wings should have looked like, because the question of insect wing origins is far from settled in the scientific community (see Grimaldi & Engel 2005, Engel et al. 2013, Ross 2017, 2022, Smith & Jockusch 2020, Akst 2022, Prokop et al. 2022). There exist very different theories for their origin without any consensus: Fossil evidence rather supports the older paranotal theory of an origin of insect wings from stiff outgrowths of the dorsal breastplates (paranota) of the exoskeleton, while evo-devo data rather support the newer exite theory (Kukalová-Peck 1997) of an origin from mobile leg appendages (exites). Actually, different lines of data equally support both theories, which are seemingly incompatible and mutually exclusive. This conundrum led to the suggestion that both theories might be true and insect wings originated as composite structures from a fusion of stiff thoracic outgrowths with mobile leg appendages. This dual origin hypothesis was also suggested in a paper co-authored by myself (Staniczek et al. 2011), but in this mainstream paper I could of course not mention the elephant in the room: such a view would make viable intermediate forms hardly conceivable, so that a saltational adaptive macro-mutation (hopeful monster) would be required, which would arguably imply intelligent design. Even though several recent studies (mainly by the research team of Tomoyasu and Clark-Hachtel at Miami University; e.g., Clark-Hachtel & Tomoyasu 2020) increasingly supported the dual origin hypothesis, there are also new studies that still support one of the single-origin scenarios, such as the recent Nature papers by Bruce & Patel (2020), who suggested “that insect wings and body walls evolved from ancient leg segments,” or by Ohde et al. (2022), who suggested “the wing origin from lateral tergum of a wingless ancestor.” Another recent study by Fisher et al. (2021) suggests that the evo-devo data “doesn’t favor either of those hypotheses about wings,” but rather, “what it says is we need other kinds of evidence” (Jockusch in Akst 2022). In other words, we are pretty much as clueless about the origin of insect wings as a century ago
The Oldest Fossil Record of Winged Insects
So, since all the alleged Devonian proto-winged insects have been debunked, what are the oldest unambiguous winged insects found in the fossil record? They were all found in Namurian sediments near the border between the Lower Carboniferous (Mississippian) and the Upper Carboniferous (Pennsylvanian), such as the rich fossil insect fauna from the Hagen-Vorhalle quarry in Germany, but many cannot be precisely dated enough to count them as oldest record (Brauckmann & Brauckmann 1992, Brauckmann et al. 1994, Prokop & Hörnschemeyer 2016). But there exist two exceptions, which happen to represent both major subgroups of winged insects (viz Palaeoptera and Neoptera).
One prominent contender is Delitzschala bitterfeldensis, which belongs to the palaeodictopterid family Spilapteridae and has even preserved the characteristic banded color pattern of the wings. It was discovered in the drilling core of a well borehole from the Bitterfeld region in eastern Germany (Brauckmann & Schneider 1996), which has been dated to a uppermost Lower Carboniferous age (Lower Namurian A/E2, Arnsbergian) of about 323 million years. Until recently this represented the oldest well-dated fossil of a winged insect (see Ross 2017) and has therefore been used as calibration point for phylogenetic trees (Wolfe et al. 2016).
More recently, an unnamed insect has been discovered in the slightly older (lowermost Namurian A/E1, Pendleian) sediments from the Upper Silesian Basin in the Czech Republic (Prokop et al. 2005), which are about 324 million years old. Based on its wing venation it could be attributed to the polyneopteran order Archaeorthoptera
The Oldest Fossil Record of Metamorphosis
Actually, the first holometabolous insects with complete metamorphosis are recorded from the same Pennsylvanian subperiod (about 314-307 million years ago) as many of the other very early winged insects (Nel et al. 2013). Molecular clock data even suggest that Holometabola are at least as ancient (about 328-318 mya) as the earliest fossil record of winged insects at all (Labandeira 2011), or place “the origin of Holometabola in the Carboniferous (355 Ma), a date significantly older than previous paleontological and morphological phylogenetic reconstructions” (Wiegmann et al. 2009a, 2009b, Misof et al. 2014). My dear colleague and frequent co-author André Nel (2019) recently commented that “the late Carboniferous was also the time of the oldest known holometabolous insects, with complete metamorphosis (wasps, beetles, scorpionflies).” Indeed, as already listed above, fossils from larval and adult holometabolous insects of different orders have been found in late Carboniferous layers (see Kukalová-Peck 1997, Nel et al. 2007, 2013, Béthoux 2009, Kirejtshuk & Nel 2013, Kirejtshuk et al. 2014, Haug et al. 2015). The mentioned holometabolan groups all have a complete metamorphosis with a pupal stage, where the caterpillar-like body plan of the larval stage is dissolved into a kind of cell tissue soup and rearranged into the very different adult body plan of the winged imago. It is hardly possible to explain an evolutionary origin of this marvellous metamorphosis at all, as the only suggested hypothesis, the so-called pronymph-hypothesis by Truman & Riddiford (1999), has to make the extremely implausible assumption that the main feeding stage (caterpillar) originated from a non-feeding late embryonal stage (pronymph) (see Bechly 2023b). Apart from that, it is certainly unexpected to find this sophisticated ontogenetic process already with early flying insects rather than after hundreds of millions of years of gradual evolution
Clocks versus Rocks
Just like in most other groups of organisms we find a great mismatch between the estimated ages by molecular clock studies and the earliest fossil record, even though Darwinism would predict that these two different lines of evidence should converge to the same true history of life. Molecular clock studies dated the origin of winged insects at about 440-370 million years ago, but the oldest fossil record is just about 324 million years ago, which implies a ghost lineage of a whopping 116-46 million years. (Gaunt & Miles 2002, Regier et al. 2004, Rehm et al. 2011, Rota-Stabelli et al. 2013, Thomas et al. 2013, Wheat & Wahlberg 2013, Misof et al. 2014, Rainford et al. 2014, Tong et al. 2015, Wang et al. 2016, Johnson et al. 2018, Montagna et al. 2019, Schachat et al. 2023).
New Study Vindicates the Carboniferous Insect Explosion
Last year a new study (Schachat et al. 2023), which reviewed the fossil and molecular evidence for the age of winged insects, fully vindicated the explosive origin of winged insects in the Carboniferous. In their abstract the authors confirmed the stark conflict between molecular clock datings and the fossil record, which requires extensive ghost lineages of unrecorded history. They were not at all convinced by any previous explanations for this conundrum and concluded:
Here, we examine the plausibility of such a gap in the fossil record, and possible explanations for it, … We do not find support for the mechanisms previously suggested to account for such an extended gap in the pterygote fossil record, including sampling bias, preservation bias, and body size.
Instead the authors suggested that the conflict between molecular clock and fossil record “is probably an analytical artifact of taxon sampling and choice of fossil calibration points, possibly compounded by heterogeneity in rates of sequence evolution or speciation, including radiations or ‘bursts’ during their early history [my emphasis].” Bursts in their early history is exactly what is described by me with the term Carboniferous Insect Explosion. I also agree that molecular clock datings are mostly rubbish, but this of course resonates better with intelligent design theory than Darwinian evolution, which would predict molecular clock studies to provide more accurate estimates on a regular basis.
The study also emphasized that different groups of insects appear in the fossil record roughly in the correct order as predicted by the sequence of branchings in phylogenetic reconstructions. Such cases of good stratigraphic fit indeed require an adequate explanation, which is arguably provided by common descent with modification. But the authors immediately qualified this result:
Obviously the fossil record is not sufficiently complete to expect that it recapitulates phylogeny with fine-tuned precision or accuracy, beyond the very broad-brush sequence of major taxa that are well represented as fossils; younger taxonomic units are expected to be less well represented as fossils, much less captured sequentially in the fossil record.
This suggests that the evidence for common descent from good stratigraphic fit may not be as strong as it is sometimes claimed.
Anyway, the abrupt appearance of winged insects with great diversity and disparity in the Carboniferous period, which we have called the Carboniferous Insect Explosion, is a phenomenon that is highly unexpected under Darwinian assumptions, but well be accommodated within an intelligent design paradigm. It represents just one of the many discontinuities in the history of life that strongly contradict the predictions from a neo-Darwinian theory of evolution. The same pattern is found in almost all groups of organisms, in all geographical regions, and in all periods of Earth’s history. This is clearly a signal in the data and not just noise. It is a signal that tells about a saltational history of life, with a series of bursts of biological creativity that can only be explained with the goal-directed infusion of new information from outside the system.
References
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