F Rosa Rubicondior: Biology
Showing posts with label Biology. Show all posts
Showing posts with label Biology. Show all posts

Tuesday 6 February 2024

Unintelligent Design - How Scientists Are Learning to Do What Creationism's 'Intelligent' Designer Found Too Difficult - Or Didn't Want To Do!


The proteins needed to create limb progenitor cells are marked with different colors under a microscope.
Images: Yuji Atsuta/Tabin lab
The Surprisingly Simple Recipe for Starting to Grow a Limb | Harvard Medical School

Visit any site of a supposed Marian miracle, such as Lourdes, now selling 'miracle cures' that almost never work and those that do can be attributed to the medication the pilgrim was receiving prior to the visit, or to spontaneous regression, the placebo effect or a psychosomatic condition, and you may find lots of crutches supposedly left there as testament to the cure of mobility disorders, but what you will never find is the artificial limb discarded by someone who had a spontaneous regeneration of an amputated limb.

Or visit any of the lucrative travelling, carefully stage-managed 'faith healing circuses' where people appear to be 'cured' of all manner of ailments at the touch of a 'healer', who, for perhaps obvious reasons, never works in a hospital, and you will never witness the regeneration of a limb, or even part of a limb. Not even a finger or toe.

And before some-one cites, the 'Miracle of Calanda', this is such an obvious hoax that it's a miracle anyone believes it.

Despite having allegedly created a universe from nothing and all living things from dirt, creationism's god appears to be incapable, even with the help of his miracle-working mother, to be able to regrow a human limb.

The problem is one of the designer's own making (if you believe creationists) because it would involve the epigenetic resetting of the cells at the end of the stump, so they become stem cells again, capable of making all the different specialist cells in a limb, like bone, muscle, skin, nerves and blood vessels and growing to the right shape in the right place. That was a once-only ability in the developing embryo.

Epigenetics, as I have written about many times, is necessary because the cells of a multicellular organism replicate the same way our single-celled ancestors did - by replicating the entire genome every time in every daughter cell. But the benefit of multicellularity is that cells are specialised so only need a few genes, not the entire genome and having the wrong genes active in a specialist cell would be detrimental, so most of them need to be switched off by the epigenetic system. A problem which could have been avoided by any omniscient, omnipotent designer by just replicating those genes that were going to be needed by the specialist cells, but not something a mindless, natural process with no foresight, no reverse gear and no means of scrapping a bad design and starting again, could have avoided.

And yet medical scientists investigating the problem believe they have discovered the basic principles involved, which turn out to be "surprisingly simple", so well within the capabilities of even creationism's rather limited god.

The scientists, led by Harvard Medical School geneticists, have published their findings in an open access paper in a Cell Press journal, Developmental Cell and explain it in a Harvard Medical School news release by Stephanie Dutchen:

Sunday 4 February 2024

Creationism in Crisis - A Strange Shaped Tree 360 Million Years Before 'Creation Week'.


Enigmatic fossil plants with three-dimensional, arborescent-growth architecture from the earliest Carboniferous of New Brunswick, Canada: Current Biology

Creationism's designer is not known for creating a design then sticking to it. If you believe creationists, it has designed something like 500,000 beetles, for example, and, although they all do basically the same thing, hundreds of different trees.

And, if you believe creationist mythology, it created almost everything on Earth, hundred, even thousands of millions of years before it created the small flat planet with a dome over it, centred on the Middles East. Sadly, the Bronze Age story-tellers who wrote about it were oblivious of what had been living 360 million years earlier in the Tournaisian age in what is now New Brunswick, Canada, so said nothing about it in their tales. They said nothing about Canada either for that matter, because they were ignorant of anywhere outside their small area of the Middle East, as can be seen from the naive way they describe their world as they imagined it.

Had they been better informed though, they might have mentioned one of the more bizarre tree designs which consisted of a straight trunk about 15 feet tall, with long thin leaves radiating out from the top third and measuring about 18 feet in length, the whole thing resembling a giant green bottle brush. It doesn't appear to have had any branches.

Fossils of this tree have been described by an international team led by Robert Gastaldo of Colby College in Waterville, Maine, USA in collaboration with Matthew Stimson and Olivia King of the New Brunswick Museum, Saint John, and Saint Mary's University in Halifax, Nova Scotia, Canada, and others.

Their work is published, open access, in Current Biology and described in a Cell Press article reprinted in Science Daily:

Saturday 3 February 2024

Unintelligent Design News - Why Women Are More Prone To Lupus Than Men - Evolution, Or Does Creationism's God Just Hate Women More?


The classic 'butterfly rash' of systemic lupus erythematosus (SLE)
Lupus and other autoimmune diseases strike far more women than men. Now there's a clue why

In my days as an operational paramedic, I once had to move a 26 your old women to hospital because lupus had made her so ill her blood pressure was below the safe level to maintain her renal function.

It was so low I couldn't even sit her up to carry her down stairs without her losing consciousness, so I had to run a couple of units of IV fluid into her to bring it up enough to make it safe to move her. She really was profoundly ill and at death's door. But such was the nature of the profession that, having delivered her safely to hospital and handed her over to the care of doctors and nurses, that was the end of my role in her care, so I never heard the outcome.

The autoimmune condition, lupus erythematosus, is caused by a malfunction of the immune system in which something triggers it to turn against the sufferer's own body instead of the invasive pathogens from which it has evolved to protect us. Although, of course, a creationist would hotly dispute the idea that a system like our immune system evolved at all, and would insist that it was intelligently [sic] designed by their favourite, evidence-free, supernatural deity without whom nothing can be created, presumably because they believe chemistry and physics don't know how to behave without a magic god telling them.

But an intelligently-designed immune system would only malfunction and turn against the person it is supposedly designed to protect if it were either incompetently designed or malevolently designed and is doing what it was designed to do - randomly increasing the suffering in the world. The evidence is that lupus is far more common in women than in men by a ratio of 9:1, which begs the question, does the designer just hate women more than men or was he more diligent when designing men's immune system then when designing women's?

The answer, as anyone who understands anatomy and physiology and particularly, evolution, will tell you, is that as an evolved system, we can expect compromises and a lack of perfection because evolution is a utilitarian process with no foresight and no reverse gear, so we are stuck with a sub-optimal immune system that evolved in an ancient ancestor, maybe even a pre-vertebrate ancestor. Certainly, all known vertebrates have one, and some, like that of bats, is far superior to ours.

Now a team of researchers at Stanford University School of Medicine, Stanford, CA, USA have worked out why lupus is far more common in women than men. Ther results are published, open access, in Cell and explained in a Stanford Medical news release. But first, a little AI background:

Malevolent Designer News - Creationism's Divine Malevolence Has Just Released An E. Coli Upgrade With Added Malice


New and highly infectiousE. coli strain resistant to powerful antibiotics - University of Birmingham

Escherichia coli is a pathogenic bacterium that is loved by creationists because they have been taken in by Michael J. Behe's book, Darwin's Black Box, that made him a millionaire because so many creationists bought it (though few appear to have read it) and which they love to wave around as 'proof' that the locally popular god exists.

Behe, a leading light in the Deception Institute, which was set up to try to win converts for fundamentalist, Bible literalist Christianity, by spreading disinformation about science, had argued, falsely, that the flagellum of E. coli must have been intelligently designed, since all the components need to be present for it to work (the 'irreducibly complex' fallacy) and it is too complex to have evolved in a single step because, so he claimed none of the components on their own could have given an advantage for natural selection to select for (which of course ignores genetic drift as a cause of evolution).

What Behe neglected to do was tell his readers that almost all the components of the flagellum and the proton pump that drives it, were present in a structure called the Type III Secretory system with which bacteria bind themselves to their host and kill them, and this could easily have evolved from simpler beginning over the billions of years that bacteria were evolving into their present forms.

Since its publication, Behe has been repeatedly told of the errors in it, and as a professional microbiologist, he should be aware of the growing body of research explaining how the E.coli flagellum evolved1,2, 3, 4, 5, yet he refused to correct his errors in later editions and continues to promote and defend the misinformation in it, whilst pocketing the royalties from sales, in a classic case of bearing false witness.

Wednesday 31 January 2024

Creationism in Crisis - Evolution Of The Human Imune System - By Repurposing An Existing Protein


The Joining chain (J chain) that helps bind and regulate the subunits that make up antibodies was evolutionarily co-opted by the human immune system from another biological process, according to a study by researchers from Penn State, the University of Maryland and the University of Chicago. The J chain, shown here in purple, assembles and stabilizes, from left, immunoglobin A (IgA) and immunoglobin M (IgM) antibodies. It is also required to move IgA and IgM across the mucus-producing tissue lining body structures with external exposure, like the intestine, nasal cavity and lungs.

Credit: Ttsz/Getty Images.
Evolutionary origin of mysterious immune system molecule in humans revealed | Penn State University

The human immune system is a problem for creationists who insist that their putative creator god designed humans perfectly but didn't create pathogenic parasites, which were created later by another creator called 'Sin' because of 'The Fall' after which this 'Sin' thing was free to create everything that increases the suffering in the world, so the question that throws creationists into confusion is when was the human immune system created?

If it was created before 'The Fall' then their designer god was planning for 'The Fall' all along and Adam & Eve had no choice but to comply with this god's plan for them, so there was no disobedience; just compliance with the plan.,

If, on the other hand, the creator had to upgrade its design later to protect its creation from pathogens, then it had failed to anticipate 'The Fall' so can't be omniscient.

And, since pathogens can and do get passed our immune defences, then a perfect, omnipotent creator did not design the immune system because it fails to work as designed, or 'Sin' can outwit it.

And now creationists have another problem, especially those who have been fooled into believing there is evidence of intelligent design to be found in 'irreducibly complex' structures and processes, because the simple biological explanation for such structures and processes is that they are composed of elements that originally evolved for other purposes and were later exapted for a novel function as part of the 'irreducibly complex' structure. For example, almost all the elements of the bacterial flagellum are to be found in the Type III secretion system (T3SS) which bacteria used to bind themselves to their potential host, but motility was such an advantage that the T3SS was repurposed for a flagellum with a few additional proteins and a slight modification of others to improve its efficiency.

Two of the components of the immune system are protein complexes which are the antibodies produced in response to infection by pathogens. These are the immunoglobin M (IgM) and immunoglobin A (IgA). Both these are stabilised by a Joining chain (a short length of protein) called the J chain. And this is the component that was co-opted from an entirely unrelated biological process, as a team of researchers at Penn State University, which included Kazuhiko Kawasaki, associate research professor of anthropology, discovered.

Their research was published a few days ago in Proceeding of the National Academy of Science (PNAS) and is explained in a Penn State University news release:

Monday 29 January 2024

Creationism in Crisis - The Billion-Year Evolutionary History of Plants On Earth


Since the first plants appeared, they have diversified into a vast range of forms, and sizes from pond scum to massive trees.

How did plants first evolve into all different shapes and sizes? We mapped a billion years of plant history to find out

Plants come in all manner of shapes and sizes, varying in complexity from simple single-celled algae, through mosses, liverworts and ferns to flowering plants and massive trees.

But how did they get this way?

A team of scientists led by Philip C J Donoghue, Professor of Palaeobiology, University of Bristol, James Clark, Research Associate, School of Biological Sciences, University of Bristol and Sandy Hetherington, Plant Evolutionary Biologist, The University of Edinburgh, set out to answer this question by looking at certain traits in each major plant group. The traits ranged from fundamentals like the presence of roots, leaves or flowers to the fine details such as the surface topography of pollen grains. All in all, the team collected data on 548 traits from more than 400 living and fossil plants, amounting to more than 130,000 individual observations.

They then used this data to plot the positions of plants, living and extinct in a 'design space', i.e., the theoretical range of possible forms for each major group.

What they found was that there tended to be a burst of diversification soon after the evolution of a major new trait, with the new lineage then tending to settle down to improve on what they had, rather than to innovate - until the next major innovation.

This what we would expect from the way a major new trait, such as the evolution of pollen as the male reproductive cell which could be transferred to the female by wind, insects, etc., so freeing the plants from the need to live in water or damp conditions so the motile male cells could 'swim' to the female, as it still does with the gametophytes - mosses, liverworts and ferns.

This innovation meant plants were not free to diversify into the dryer land between rivers, lakes and coastal margins and so colonise much more of the planet.

The same phenomenon is seen in animals where, for example, terrestrial living freed the early amphibians from dependence on water, except to breed, and the evolution of eggs, freed them even from that dependence; the evolution of flight freed the birds and bats to diversify into the new niches now open to them.

The team's work was published, open access in Nature Plants and is the subject of an article in The Conversation by the three lead authors. Their article is reprinted here under a Creative |Commons license, reformatted for stylistic consistency:

Creationism in Crisis - How An Iconic Australian Plant Originated in Africa - 132 Million Years Before 'Creation Week'


Banksia spinosa inflorescence

Banksias are iconic Australian plants, but their ancestors actually came from North Africa

No real scientists these days sets out to refute creationism as such, but most do anyway, because creationism is so counter-factual that almost any scientific facts, especially in the fields of biology, cosmology, archaeology, geology and palaeontology refute it. It takes a resolute and determined ignoramus to not be aware of that. The problem creationists have is that they get all their beliefs from an ancient text that is demonstrably wrong, even when explained away as allegorical or metaphorical. It is neither. It is quite simply wrong on every level.

So, creationists are left desperately trying to defend the childishly absurd claim that the entire Universe, including Earth and all living things on it, were all created out of nothing in a few days, about 10,000 years ago, by a magic man also made of nothing who designed himself before he existed then self-assembled according to that plan, with all the complexity and information needed to create and micromanage an entire Universe.

This, despite the fact that there are fossil remains of plants and animals from hundred, even thousands of millions of years before then and despite the fact that all the evidence points to a long, slow, evolutionary process of divergence from a common ancestor that lived well over a billion years ago, which was itself the result of a symbiotic associations of much earlier organisms.

One such paper, which casually and incidentally refutes creationism, recently published in Perspectives in Plant Ecology, Evolution and Systematics by three Australian botanists and plant ecologists and a South African Professor of botany, traces the origin of the family of iconic Australian plants, the Banksias, to North West Africa, 132 million years ago.

The story of this migration meshes in with the sciences of plate tectonics and oceanography allowing the plants to migrate across then contiguous land masses from what is now North West Africa to what is now Australia via South America and Antarctica, as land-masses split and diverged and sea-levels rose and fell to reveal land bridges where there is now ocean.

How they discovered this is the subject of an article in The Conversation by the four scientists. Their article is reprinted here under a Creative Commons licence, reformatted for stylistic consistency:

Creationism in Crisis - Something For Creationists to Squawk About - Parrot-Like Dinosaurs from 67 Million Years Before 'Creation Week'


OSU-CHS student discovers new dinosaur species, publishes findings | Oklahoma State University

Between about 67 and 66 million years ago, during a period that geologists call the Maastrichtian, there was a thriving ecosystem of dinosaurs in what is now the Hell Creek formation which spans parts of Montana, Wyoming, and North and South Dakota. We know this because their remains are frequently found in this fossil-rich formation known as the Hell Creek Formation.

The great thing about this formation is the way, as the layers built up, nearby volcanoes periodically spread a layer of ash (or tufa) over it forming neat bands that can be accurately dated using one of the most accurate radiometric dating methods - Uranium-Lead (U-Pb) in zircons. This gives a maximum and minimum age of the fossils found between these layers of tufa.

I wrote about U-Pb dating in a recent blogpost, but for the sake of creationists who are about to squawk "Radiometric dating is false!", I'll expand on what I said here:

Sunday 28 January 2024

Unintelligent Design - How A Virus Saved The Unintelligent Designer's Blushes Early In Multicellular History


A virus that infected animals hundreds of millions of years ago has become essential for the development of the embryo

I've remarked before how similar biological systems are to the machines the late William Heath Robinson designed for solving simple, everyday problems. Simple solutions were eschewed for more complicated ones and unlikely items were used in ways they weren't intended for, such as a grandfather clock standing on a piano to support a platform balanced on top. Everything was held together by pieces of knotted string and labour-saving devices took far more people than would have been needed to do the job more simply.

And yet, the whole contraption worked, or at least looked as though it would if were ever made, but take any part away and the whole thing would fail, in an example of what creationists call 'irreducible complexity'.

So, let's pretend that creationism's, 'intelligent'[sic] designer really is behind the design of living organisms and see how closely Heath Robinson unwittingly parodied it:
Just such an example of a Heath Robinson machine in biology was revealed a few days ago in an open access paper published in Science Advances, explaining how a virus which became incorporated in the genome of an early multicellular organism provided a solution to a problem of the designer's own making. The problem it solves was how to overcome the problem created by choosing the same method of cell replication in multicellular organisms that single-celled organisms use, where the entire genome needs to be replicated at each division.

The entire 'point' of multicellularity, and what gave it its success over single-celled organisms is division of labour, in other words, specialisation, so the organisms can be divided into tissues and organs that perform a specialised task. This means that every cell has to have the potential to carry out every function, in the genes it inherits from its parent cell, yet only a few genes are need for its particular specialty.

The process by which this is achieved is the complicated epigenetic system which turns off unneeded genes as the cells differentiate into different cell lines in the developing embryo, and these settings can't normally be reversed.

However, the sperm and egg which then fused to form the zygote from which a new embryo develops, are themselves specialised cells with all the epigenetic settings of their parent cells with an additional few of their own, and these are inherited by the zygote, so to make cell differentiation possible again, the zygote is quickly (within minutes of fertilisation) reset to a state of totipotency.

So, to overcome the epigenetic settings problem that is a problem of the designer's own making, the zygote needs to be epigenetically reprogrammed and this happens in two stages: first to produce a 'totipotent' cell with the potential to produce all the different cells in the embryo as well as the placenta, umbilical cord, and amniotic sack in which the embryo will develop, and then, soon after cell division begins, 'pluripotent' cells from which the different stem cells for the required specialised cell lines will develop.

How this was helped by a virus is the subject of the paper by researchers from the Spanish National Cancer Research Centre (CNIO), Madrid, Spain. First, a little AI background:

Saturday 27 January 2024

Creationism in Crisis - A Multicellular Organism 1.63 Billion Years Before 'Creation Week'


Fig. 1. Transmitted-light (TL) photomicrographs of Q. magnifica from the Chuanlinggou Formation.
(A to D and K) Filaments with cells of varying length and width. (E) Four-celled filament with hemispherical terminal cell. (F and G) Filament with notably decreasing cell width toward one end. Note that (F) and (G) represent the same specimen; (F) lost the narrowest part of the filament as shown in (G). (H to J) Filaments displaying more uniformity of cell dimensions. (L) Two-celled filament with ovoid terminal cell. All specimens were handpicked from organic residues of acid maceration and photographed in wet mounts, except for (K), which was photographed from a permanent strew mount. Solid and empty gray triangles in (A), (C), and (K) indicate the longest and the shortest cells, respectively, within single filaments. tb, transverse band (interpreted as cross wall); tr, transverse ring (interpreted as partially preserved cross wall). Scale bar, 50 μm [(A) to (E), (I), (J), and (L)] and 100 μm [(F) to (H) and (K)].
Fossils from North China indicate eukaryotes first acquired multicellularity by at 1.63 billion years ago---- Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

As though the abundant evidence of life on earth before about 10,000 years ago wasn't bad enough for creationists who believe the Universe and everything in it were was magicked out of nothing in 6 days around about then, a team of scientists led by led by Professor ZHU Maoyan from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NGIPAS), has now pushed the date of oldest-known multicellular, eukaryote organism back another 70 million years to a whapping 1.63 billion years before the supposed 'Creation Week'.

This would mean, if their superstition had any merit that creationists believe Earth has been around for just the last 0.0006% of the time that multicellular eukaryotes have existed on it.

And they wonder why people laugh!

The fossils were discovered in the Yanshan area of North China in the late Paleoproterozoic Chuanlinggou shale Formation which is about 1,635 million years old. The age of the fossils is constrained by a layer of volcanic ash ~40 m above the fossil horizon in the Kuancheng area, which has yielded a U-Pb zircon age of 1634.8 ± 6.9 Ma (23).

All complex life on Earth, including diverse animals, land plants, macroscopic fungi and seaweeds, are multicellular eukaryotes. Therefore, multicellularity is key for eukaryotes to acquire organismal complexity and large size, and often regarded as one major transition in Earth’s life history by scientists. However, it is still poorly understood when eukaryotes first evolved this innovation in their deep evolutionary history.

Fossil records with convincing evidence show that eukaryotes with simple multicellularity already appeared at 1.05 billion years ago, including red and green algae, and putative fungi. Older records claimed to be multicellular eukaryotes, but most of them are controversial due to their simple morphology and lack of cellular structure.

Unintelligent Design - The Unintelligent Evolution of Sea Grasses 100 Million Years Before 'Creation Week'


Little Neptune Grass (Cymodocea nodosa).

Photo: Thorsten Reusch, GEOMAR
Use it or lose it: How seagrasses conquered the sea - GEOMAR - Helmholtz-Zentrum für Ozeanforschung Kiel

Sea grasses are the only flowering plants to become fully submerged, having evolved from three independent lineages some 100 million years ago in fresh water and transitioned into marine plants. This appears to have been facilitated some 86 million years ago by a whole genome tripling, which created plenty of spare DNA which could mutate harmlessly to create new genetic information - something deemed 'impossible' by creationist dogma. Since then, they have undergone further evolutionary adaptation by gene loss - something else that creationist dogma says is impossible.

Now an international group of 38 researchers coordinated by Professor Dr. Yves Van de Peer, Ghent University, Belgium, Professor Dr. Jeanine Olsen, University of Groningen, Netherlands, Professor Dr. Thorsten Reusch, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany, Dr. Gabriele Procaccini, Stazione Zoologica Anton Dohrn of Napoli, Italy, and the Joint Genome Institute, Berkeley, California, United States of America, sequenced and analyzed the genomes of three of the most important seagrass species – the iconic Mediterranean endemic Neptune grass (Posidonia oceanica), the broadly distributed Little Neptune grass (Cymodocea nodosa) and the Caribbean endemic Turtlegrass (Thalassia testudinum), to discover what evolutionary changes had enabled this transition.

Anyone who has holidayed on the Mediterranean coast may be familiar with the 'Poseidon balls' that wash up on beaches. These example of emergence of order from chaos are the result of the fibrous remains of Poseidon grass leaves being rolled along the seabed at the tidal interface to form long rolls which then break up and get rolled further into balls, as I relate here.

But the question the team addressed was not how the Poseidon balls form but how did the sea grasses evolve? This is the subject of their paper in Nature Plants and a press release from GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany:

Friday 26 January 2024

Closing In On Abiogenesis - How Amino Acids Become Peptides in Water Droplets - No Magic Required


A tripeptide (example Val-Gly-Ala) with green marked amino end (L-valine) and blue marked carboxyl end (L-alanine)
Chemistry professor R. Graham Cooks expands research of water droplet interfaces that offer the secret ingredient for building life - Purdue University Department of Chemistry

One of the puzzles of how the earliest proteins were built from amino acids was that the reaction of joining two amino acids together is a condensation reaction in which a molecule of water is eliminated when the -C-OH of one amino acid binds to the H2N-C- of the other amino acid in what is known as a peptide bond:

-C-OH + H2N-C- → -C-NH-C + H2O;

but how could this happen in an aqueous solution?

In 2022, Professor R. Graham Cooks' team at Purdue University found the answer: It is due to the peculiar properties at the surface of droplets of water. Because of the way electrostatic forces align the water molecules at the surface, it behaves as though it is extremely dry, and highly acidic. These conditions provide the perfect conditions for a condensation reaction to occur, resulting in a peptides.

Droplets of water are everywhere in nature, from the spray of breaking waves, the splash of raindrops, waterfalls, trickling streams to aerosols of water in clouds and fog.

And Professor Cooks's team at Purdue have now shown that these conditions also occur at the macro, centimeter scale as water evaporates on, for example rocks or the margins of hydrothermal pools. They have also shown that these reactions, in the presence of oxazolones (produced by the dehydration of amino acids) preserve the chirality of the peptides so the resulting peptides are 'L' enantiomers, as found in all living organisms.

As the Purdue University press release says:
The study adds to the body of evidence that the surface of water drops represents a uniquely active physical and chemical system. Present are very high electric fields and extreme acidity that drives dehydration of amino acids to form peptides. Studies of the chemistry at water droplet interfaces offer new insights into the early stages of life's chemical evolution.
Significance

This study provides experimental evidence identifying oxazolones as the key intermediates in prebiotic peptide synthesis. These compounds yield the dipeptides upon reaction with water and generate tripeptides in the presence of other amino acids. These key steps in protein formation occur in pure water droplets. Amino acid chirality is preserved in forming the oxazolone and the addition of amino acids during peptide chain extension shows a strong chiral preference, viz. the aqueous droplet chemistry represents a simple route to chirally pure polypeptides. A direct connection between this intermediate and the dipeptide isomer, oxazolidinone, is demonstrated by simple hydration/dehydration. The oxazolone/oxazolidinone-mediated mechanism also occurs in macroscopic wet–dry cycling, establishing a strong connection between macroscopic and microscopic peptide synthesis.

Abstract

Peptide formation from amino acids is thermodynamically unfavorable but a recent study provided evidence that the reaction occurs at the air/solution interfaces of aqueous microdroplets. Here, we show that i) the suggested amino acid complex in microdroplets undergoes dehydration to form oxazolone; ii) addition of water to oxazolone forms the dipeptide; and iii) reaction of oxazolone with other amino acids forms tripeptides. Furthermore, the chirality of the reacting amino acids is preserved in the oxazolone product, and strong chiral selectivity is observed when converting the oxazolone to tripeptide. This last fact ensures that optically impure amino acids will undergo chain extension to generate pure homochiral peptides. Peptide formation in bulk by wet-dry cycling shares a common pathway with the microdroplet reaction, both involving the oxazolone intermediate.

Qiu, Lingqi; Cooks, R. Graham
Oxazolone mediated peptide chain extension and homochirality in aqueous microdroplets
Proceedings of the National Academy of Sciences (PNAS) 121(2). DOI: 10.1073/pnas.2309360120

© 2024 PNAS.
Reprinted under the terms of s60 of the Copyright, Designs and Patents Act 1988.
And so that day that creationist frauds must be dreading, when science finally closes their favourite gap in which to force-fit their ever-shrinking little god finally slams as shut as all the other gaps it used to occupy in the minds of scientifically illiterate believers, gets a little closer. Only yesterday we learned how simple metabolic biochemical cycles can be produced from simple precursors, all of which were present on the pre-biotic Earth and without protein enzymes, and here we see how the proteins that could catalyse and improve those processes could also arise from simple precursors that were also present.

I wonder what disinformation the frauds who feed pseudo-science to the creation cult are preparing for that eventuality.

Ten Reasons To Lose Faith: And Why You Are Better Off Without It

This book explains why faith is a fallacy and serves no useful purpose other than providing an excuse for pretending to know things that are unknown. It also explains how losing faith liberates former sufferers from fear, delusion and the control of others, freeing them to see the world in a different light, to recognise the injustices that religions cause and to accept people for who they are, not which group they happened to be born in. A society based on atheist, Humanist principles would be a less divided, more inclusive, more peaceful society and one more appreciative of the one opportunity that life gives us to enjoy and wonder at the world we live in.

Available in Hardcover, Paperback or ebook for Kindle


What Makes You So Special? From The Big Bang To You

How did you come to be here, now? This books takes you from the Big Bang to the evolution of modern humans and the history of human cultures, showing that science is an adventure of discovery and a source of limitless wonder, giving us richer and more rewarding appreciation of the phenomenal privilege of merely being alive and able to begin to understand it all.

Available in Hardcover, Paperback or ebook for Kindle




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Malevolent Designer News - How The SARS-CoV-2 Virus Has Been Redesigned to Have Another Go


The emergence of JN.1 is an evolutionary ‘step change’ in the COVID pandemic. Why is this significant?

To anyone but a reality-denying creationist, the SARS-CoV-2 virus that causes COVID-19, is a classic example of evolution by natural selection, as it continually mutates and those mutations that make it more successful are retained, so it continually improves in its ability to infect and be passed on to another victim, so producing more offspring in the virus gene pool than rival versions.

The latest version to gain predominance, JN.1, currently spreading across the world, is yet another variation on the omicron version, which itself ousted delta as the predominant variety. This new improved version may prove to be so different to omicron that is should be given a new Greek letter designation.

One point that shouldn't go unnoticed is that because, unlike the original, the virus now exists in an environment in which most of its potential victims have a degree of immunity to it, either by vaccination or by previous infection. Because that immunity usually means the ability to produce antibodies to the 'spike' proteins on the surface of the virus, most of the mutations of progressively more successful variants are in the genes that code for those proteins - making it more difficult for antibodies to bind to them.

To a creationist, the SARS-CoV-2 virus, like all the other pathological viruses, presents the paradox of trying to believe their putative designer god is the supreme ruler of and creator of everything in, the universe and is the only entity capable of creating biological organisms, but, because it is omnibenevolent, it would not have designed SARS-CoV-2 and would not be responsible for continually redesigning it to continue making us sick, by evading the immune system it supposedly also designed to protect us from viruses and other pathogens.

Curiously, creationists who continually present what they think is evidence of design as evidence for their magic creator on the grounds that it is the only entity capable of biological design, never use evidence of malevolent design as evidence for the same magic creator. That has to be ascribed to another entity with even greater powers than their supposedly supreme-in-all-things god and with the ability to outwit it, even though that claim is blasphemous within their own religious beliefs. They need to hold those two diametrically opposite views of 'creation' simultaneously to continue to deny the evidence for evolution by natural selection of which the SARS-CoV-2 virus is a perfect example.

And those creationists who do actually believe the religion they purport to believe and who won't contemplate blasphemy, have no recourse but to believe that the SARS-CoV-2 virus was not only designed by their putative designer god but that it also regularly updates it to continue making us sick despite the efforts of biomedical scientists, because the alternative it to accept the unthinkable and ascribe it all the a god-free natural process of evolution by natural selection, just as science claims.

The following article by Suman Majumdar, Associate Professor and Chief Health Officer - COVID and Health Emergencies, Burnet Institute; Brendan Crabb, Director and CEO, Burnet Institute; Emma Pakula, Senior Research and Policy Officer, Burnet Institute; and Stuart Turville, Associate Professor, Immunovirology and Pathogenesis Program, Kirby Institute, University of New South Wales, Australia, explains why the emergence of the JN.1 variant of SARS-CoV-2 is a significant evolutionary step change. It is reprinted from The Conversation under a Creative Commons licence, reformatted for stylistic consistency:

Thursday 25 January 2024

Unintelligent Design - How Ovulation Goes Wrong Because It Wasn't Intelligently Designed


Gene expression atlas captures where ovulation can go awry | Cornell Chronicle

Back in the late 1960s and early 1970, in what seems like a different lifetime now, I was a senior research assistant in the Oxford University/MRC Neuroendocrinology Research Unit, researching the hormonal control of ovulation in guinea pigs. Two of our tools were radioimmunoassays I had adapted for measuring extremely low levels of a hormone in guinea pig anterior pituitary glands known as luteinizing hormone (LH), and another similar assay for measuring the level of the steroid progesterone in guinea pig blood.

Sadly, having worked for close on two years towards producing a research paper with hundreds of assay results, thousands of microscope slides, hundreds of electron micrographs and a freezer full of samples waiting to be assayed, the government pulled the rug from under our feet by withdrawing our research funding, and I was made redundant, so my work was never published. Disillusioned and with a young family to support, I left research and perused a career in the NHS Ambulance Service instead - but that's a different story, and not relevant to the subject of this blogpost, which illustrates how much science has progressed in the last 50-60 years.

Researchers are no longer researching the hormonal control of ovulation but the fine details of the genetic control of the process of ovulation at the cell level, and what they've found is that the process is far from intelligently designed by anything resembling a perfect, omniscient, omnipotent designer. It is a process that is so complex that it can, and does, go wrong. An intelligent designer who didn't want random women to be unable to shed viable eggs, could have designed a less complicated process, but you can depend on creationism's putative intelligent[sic] designer to never do something simple when there is a far more complicated and wasteful way to achieve the same result.

The research, published a few days ago in Proceedings of the National Academy of Sciences, was led by Iwijn De Vlaminck, associate professor of biomedical engineering in Cornell Engineering, and Yi Athena Ren, assistant professor of animal science in the College of Agriculture and Life Sciences. The paper’s lead author is Madhav Mantri, Ph.D., now a postdoctoral researcher at Stanford University.

The team used a form of RNA tagging to map the gene expressions that occur during ovarian follicle maturation and ovulation in mice.

This spatial transcriptomics map depicts the cell types of a mouse ovary undergoing hormone-induced ovulation
The research is explained in a Cornell University Press release:

Wednesday 24 January 2024

Malevolent Designer News - How Bacterial Pathogens Are Cleverly Designed to Invade Their Victim's Body


Functional model for Yen-Tc toxicity. Following ingestion of the Tc, it is likely that the surface-bound chitinases bind to and/or degrade the chitin-rich peritrophic membrane of the insect midgut. Cell surface recognition is likely facilitated by motifs within the A subunits prior to internalization. Similarities to the well characterized bacterial binary toxin systems (e.g., anthrax, cholera, diphtheria) suggest a mechanism involving receptor-mediated endocytosis followed by pore formation and translocation of the B and/or C components into the cytosol (I), although alternative mechanisms (e.g., II, III) cannot be ruled out.

Landsberg, MJ., Jones, SA., Rothnagel R., et al (2011)
24-01-18 | Max Planck Institute of Molecular Physiology

Imagine you're in charge of an invading army laying siege to your enemy's outer defences. How do you neutralise them?

One way would be to send a small group of soldiers, packed with high explosives and deadly toxins on a kamikaze mission into the defences, with instructions to detonate their explosives and so spread the toxins when inside to destroy the defences and kill the defenders. You could improve on that by removing any temptation the suicide bombers might have to not detonate their defences by automating the trigger to fire as soon as they encountered the defender.

That's exactly what a team at the Max Planck Institute for Molecular Physiology (MPI MOPH), Dortmund, Germany, have found bacteria use to gain access to their victim’s body and make their hosts sick and die. The team, led by Stefan Raunser, Director of MPI MOPH, have published their findings, open access, in Nature Microbiology. Their work is described in a MPI MOPH press release:

Tuesday 23 January 2024

Creationism in Crisis - Flying Reptiles In The Mendip Hills - 200 Million Years Before 'Creation Week'


Showing partial skeleton of gliding reptile Kuehneosaurus on rock from Emborough.
Credit: David Whiteside
January: Ancient flying reptiles | News and features | University of Bristol

200 million years, give or take a few thousand years, before creationists believe Earth and life on it were all created by magic from nothing in a week, gliding lizard-like reptiles related to ancestral crocodiles, were gliding from tree to tree, and probably hunting flying insects, in what is now the Mendip Hills, near Bristol, UK. The area around Bristol was then an archipelago of islands in a sub-tropical, shallow sea.

Fossil remains of these reptiles were found by University of Bristol Masters student Mike Cawthorne, researching numerous reptile fossils from limestone quarries, in what was then the biggest sub-tropical island at the time, called the Mendip Palaeo-island.

As the Bristol University press release explains:
The study, published today in Proceedings of the Geologists’ Association, also records the presence of reptiles with complex teeth, the trilophosaur Variodens and the aquatic Pachystropheus that probably lived similarly to a modern-day otter likely eating shrimps and small fish.

The animals either fell or their bones were washed into caves and cracks in the limestone.

“All the beasts were small,” said Mike. “I had hoped to find some dinosaur bones, or even their isolated teeth, but in fact I found everything else but dinosaurs.

“The collections I studied had been made in the 1940s and 1950s when the quarries were still active, and palaeontologists were able to visit and see fresh rock faces and speak to the quarrymen.”

Professor Mike Benton, from Bristol’s School of Earth Sciences, explained: “It took a lot of work identifying the fossil bones, most of which were separate and not in a skeleton.

“However, we have a lot of comparative material, and Mike Cawthorne was able to compare the isolated jaws and other bones with more complete specimens from the other sites around Bristol.

“He has shown that the Mendip Palaeo-island, which extended from Frome in the east to Weston-super-Mare in the west, nearly 30 km long, was home to diverse small reptiles feeding on the plants and insects.

“He didn’t find any dinosaur bones, but it’s likely that they were there because we have found dinosaur bones in other locations of the same geological age around Bristol.”

The area around Bristol 200 million years ago in the Late Triassic was an archipelago of small islands set in a warm sub-tropical sea.

Bristol’s Dr David Whiteside added: “The bones were collected by some great fossil finders in the 1940s and 1950s including Tom Fry, an amateur collector working for Bristol University and who generally cycled to the quarries and returned laden with heavy bags of rocks.

“The other collectors were the gifted researchers Walter Kühne, a German who was imprisoned in Great Britain in the 2nd world war, and Pamela L. Robinson from University College London. They gave their specimens to the Natural History Museum in London and the Geological collections of the University of Bristol.”
Abstract

During the Late Triassic and Early Jurassic, the area around Bristol and South Wales was an archipelago of islands occupied by diverse small-sized tetrapods. The largest of these palaeo-islands was Mendip Island, now forming the Mendip Hills, and the location of some famous fossiliferous sites. These sites have not been described in detail before, and we present new data on three of them. Highcroft has yielded only sparse remains of rhynchocephalians, and Batscombe famously the gliding reptile Kuehneosuchus latissimus. Emborough yielded the richest fauna of the three, abundant pseudosuchians including crocodylomorphs as well as the gliding reptile Kuehneosaurus latus, rare trilophosaurs, a probable thalattosaur, rhynchocephalians, and the mammal Kuehneotherium. These include some of the last known taxa of clades that died out in the end-Triassic mass extinction. We report a new taxon of sphenosuchid crocodylomorph similar to Saltoposuchus and a find of Pachystropheus, an aquatic reptile shared with Holwell and the bedded Rhaetian at Blue Anchor Point, Aust and Westbury Garden Cliff. The discovery of a fish vertebra strengthens the model of Emborough fissure filling in a marginal marine location. The Emborough fauna differs from coeval assemblages from Cromhall, Tytherington and Ruthin in the scarcity of sphenodontians and the absence or great rarity of procolophonids as well as the abundance of kuehneosaurids and crocodylomorphs.

1. Introduction

The Triassic (252–201 Ma) was a crucial time in the recovery, restructuring and diversification of vertebrate life (Benton and Wu, 2022). Many modern groups including lissamphibians, turtles, lizards, crocodiles, and mammals originated or diversified in the Late Triassic, part of the process of the recovery of life from the end-Permian mass extinction, but stimulated by the Carnian Pluvial Episode 233–232 Ma, following which climates became more arid, and the new groups, including dinosaurs, had opportunities to diversify (Brusatte et al., 2010; Chen and Benton, 2012; Benton et al., 2014; Bernardi et al., 2018; Dal Corso et al., 2020; Benton 2021; Benton and Wu, 2022).

The end-Triassic mass extinction (ETME), 201 Ma, was probably caused by sharp warming from greenhouse gases erupted by the Central Atlantic Magmatic Province (CAMP), associated with the beginning of rifting and opening of the North Atlantic (Blackburn et al., 2013). The environmental crisis led to widespread extinctions of many tetrapod clades including procolophonids, placodonts, kuehneosaurids, thalattosaurs, allokotosaurians and phytosaurs. Many pseudosuchians such as the rauisuchids also became extinct but the Crocodylomorpha survived leading to the modern living crocodilians. Whether the ETME was a single crisis at the end of the Triassic or began minimally 100 ka before the earliest known eruptions (Davies et al., 2017) is debated. Indeed, there is good evidence for several earlier events, one at the Norian–Rhaetian boundary (Rigo et al., 2020.1) and one equivalent to the middle of the Cotham Member in the British Rhaetian succession (Wignall and Atkinson, 2020.2), both marked by carbon isotope excursions and evidence for substantial loss of marine species. The spacing of these events is entirely dependent on estimates of the duration of the Rhaetian, with its beginning variously dated at 205.7 Ma and 201.7 Ma, making the stage either 4.2 or 0.2 Myr in duration (Maron et al., 2015; Ruhl et al., 2020.3).

These considerations around the importance of the Triassic as a whole, and the Late Triassic in particular, in documenting the origin of modern ecosystems on land and in the sea, as well as the evidence for phased bursts of extinction through the Rhaetian, place fresh importance on understanding the Late Triassic and Early Jurassic fossil faunas found bordering the Bristol Channel, around Bristol and in South Wales. These faunas are preserved across a sub-tropical archipelago (Fig. 1) in fissure fillings, deposits of soil and other debris accumulated in karstic cave systems (Whiteside et al., 2016; Lovegrove et al., 2021.1). First finds were isolated bones of the sauropodomorph dinosaur Thecodontosaurus in the Worrall Road Quarries in Bristol (Riley and Stutchbury, 1836, Riley and Stutchbury, 1840; Ballell et al., 2020.4) and then mammal remains at Holwell Quarry (Moore, 1859), and later recognition by Charles Moore that these were Mesozoic-aged fissures eroded into Carboniferous limestone. The study of the fissures began again in the late 1930s and the 1940s with the work of Walter Kühne and his discoveries of mammal remains at Holwell and elsewhere (Kühne, 1949; Savage, 1993; Whiteside and Duffin, 2017.1; Benton et al., 2024).
Fig. 1. The Bristol palaeo-archipelago, showing island locations in the latest Triassic (early Rhaetian). Overview of the whole area, showing the Mendip Palaeoisland. The blue shallow seas between the islands are areas with deposition of the Westbury beds. Fissure fill localities are marked in red, bone beds in orange. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Map from Lovegrove et al. (2021.1).
The fissure faunas have been reviewed several times (Robinson, 1957a; Fraser, 1994; Whiteside et al., 2016), and one of the key land masses was the Mendip Palaeoisland (Lovegrove et al., 2021.1), the site of five fossiliferous fissure sites, namely Emborough, Batscombe, Highcroft, Holwell, and Windsor Hill (Fig. 1). These sites have been reported before (Robinson, 1957a; Fraser, 1994) although not extensively, but Emborough has been featured in several publications (Robinson, 1957a, Robinson, 1957.1b, Robinson, 1962) because of the remarkable specimens of kuehneosaurids, also abundantly represented at Batscombe. These unique finds, however, are not replicated at other fossiliferous fissure sites on the Mendip Island, even at Highcroft and Holwell (Fig. 1). Likewise, although Emborough has produced abundant remains of archosauromorphs, these are very rare at Holwell.

Our aim is to document three of the five Mendip Island fissure localities, Emborough, Batscombe, and Highcroft, whose terrestrial assemblages have not been published in detail before, and to present data on geology and taphonomy as well, to allow comparison with the other Late Triassic fissure faunas around Bristol and in South Wales.
Anatomical abbreviations. a, anterior; ac, anterior condyle; ace, acetabulum; amafe, anterior margin of antorbital fenestra; amp, amphicoelous; ampl, amphyplatyan; an, angular; ap, anterior projection; ar, articulation(s); artf, facet for the articular bone; at, attachment; bic, bicapitate; bs, basipterygoid; c capitulum; ca, capitelum; ce, centrum; cfo, coracoid foramen; cn, canal; co, condyle; cx, convex (surface); di, diapophysis; dis, distal; desf, surface contacting dentary; dpc, deltopectoral crest; dor, dorsal; ec, ectopterygoid; ect, ectepicondyle; ent, entepicondyle; er, erupting; fc, fibular contact; fcp, facial process; fct, facet; fl, flat surface; fla, flange; fo, foramen; fos, fossa; gl, glenoid; gr, groove; hd, head; itfe, inferior temporal fenestra; l, lateral; ls, ligament scar; mc, medial condyle; mk, meckelian; ml, midline; ms, muscle scar; ne, neural; palf, facet for the palatine; pc, pleuracrodont; pco, posterior condyle; pozy, postzygapophysis; pr, process; prz, prezygapophysis; pm, prominance; po, posterior; pp, parapophysis; prx, proximal; rid, ridge(s); saf, surangular facet; sar, sacral rib; sc, supinator crest; ser, serrations; sf, surface; sh, shallow; slf, shelf; sp, spine; spl, splenial; stfe, superior temporal fenestra; sut, suture; t tuberculum; th, tooth (teeth); tb, tubercle; tc, trochlear groove; tcn, tibia contact; tr, trochanter; tv, transverse; ven, ventral; vmaf, ventral margin for adductor fossa; wr, wear; zy, zygapophysis.

Institutional acronyms. AMNH, American Museum of Natural History, New York, USA; BRSMG, Bristol Museum and Art Gallery, Bristol; BRSUG, University of Bristol, Geology Collection; NHMUK, Natural History Museum, London; SMNS, State Museum of Natural History Stuttgart, Germany; TTU, Museum of Texas Tech University, Lubbock; UCMP, University of California Museum of Palaeontology; UNC, Department of Geological Sciences, University of North Carolina at Chapel Hill.


Cawthorne, Michael; Whiteside, David I.; Benton, Michael J.
Latest Triassic terrestrial microvertebrate assemblages from caves on the Mendip palaeoisland, S.W. England, at Emborough, Batscombe and Highcroft Quarries
Proceedings of the Geologists' Association (2024) S0016787823000998. DOI:10.1016/j.pgeola.2023.12.003

Copyright: © 2024 The authors.
Published by Elsevier B.V., Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
But then what did the authors of Genesis know about the climate in, and location of, what is now south-east England 200 million years earlier, when they didn't even know about Europe and thought Earth was small, flat and just a few thousand years old? This is why so much of it is now having to be reclassified as 'allegorical' or 'metaphorical' by mainstream Christians, leaving only a dwindling cult of fruitloop fanatics still believe it is the inerrant word of an omniscient creator god, laughable though that demonstrably absurd, childish notion is.

Ten Reasons To Lose Faith: And Why You Are Better Off Without It

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What Makes You So Special? From The Big Bang To You

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