F Rosa Rubicondior

Monday 18 March 2024

Religion News - People Who Believe Absurdities Will Commit Atrocities!


Why Religions Seem to Involve Outlandish Beliefs | Psychology Today

It's axiomatic that people who can believe absurdities can be persuaded to commit atrocities.

One only need look at the history of just about every world religion to know that is especially true of people who hold to religious beliefs, yet most religious people will look at other religions and wonder how on Earth they can believe that nonsense, while having no understanding why others who look at their beliefs have the same thoughts.

How many devout Christians, for example, would find nothing strange in the belief that the sun was swallowed each evening by the goddess Isis, who then gave birth to it every morning or that ancient Celtic chiefs physically mated with the Earth goddess at Tara to unite the Irish people with the land they lived on?

Yet those same Christians have no difficulty believing that the blood sacrifice of an innocent person can atone for collective 'sins' inherited from ancient ancestors or that the dismembered bodies of ancient holy men can somehow persuade a god to change his perfect plans for their better one, or an omniscient, omnibenevolent god needs to be told about a wrong and why if should be righted, or a mind-reading god needs to be told their thoughts.

And a Moslem who believes the founder of their religion split the moon in half and flew to Heaven on a magic flying creature finds it incomprehensible that saying prayers to a painting of an ancient holy man or priest can change the direction of the universe, or that the prohibition on 'graven images' doesn't apply to gold-covered icons or depictions of a god nailed to a stick, worn by people who believe tiny images of a blood sacrifice or miniature instrument of torture worn around their neck protects them from evil spirits?

There are even people who believe the sun can be made to perform strange maneuvers in the sky while no-one else on Earth noticed it and without Earth itself needing to suddenly change its speed and direction of rotation or orbital path round the sun. Even the leaders of a major branch of Christianity, with a whole panel of expert scientific advisors, believe that really happened and continue to send people to Fatima where it is alleged to have happened - just one of the many equally implausible and evidence-free beliefs orthodox Catholics needs to hold.

Even coeliac suffering Catholics can believe a piece of wafer, when the right spells are cast over it, miraculously becomes the body of a dead god to be consumed in a cannibalistic ritual, while knowing they need to avoid eating it to avoid the consequences of gluten intolerance! That's a condition of belonging to a cultural group called 'Catholics'.

How Science Works - Checking, Rechecking and Questioning What We Think We Know. The Only Certainty Is That There Are No Certainties


New research suggests that our universe has no dark matter | About us
A leading theoretical physicist has questioned whether dark matter really exists.

Dark Matter is a placeholder for what appears to be mass without substance which suffuses the universe, observable only by the gravity it exerts and thought by mainstream cosmologists to account for 27% of the matter in the universe with 'ordinary' matter making up just 5%. The rest - 68% - being composed of dark energy, another placeholder for something theory says should be there to account for the expansion of the universe, but which we don't have a model for in the standard model of particles and related fields.

I don't pretend to understand this stuff, but I'll post it here by way of a rebuttal of creationist claims that scientists devise experiments to try to prove preconceptions and that peer-review is just to ensure conformity to scientific orthodoxy.

Besides, the HTML coding is the sort of challenge I enjoy.

In fact, science is about continued reassessment and revision with names made not by confirming preconceptions but by overthrowing established consensus or exposing flaws in it which require further investigation. The leading theoretical physicist is Professor Rajendra Gupta of the Faculty of Science, University of Ottawa, Canada, who has just published a paper in The Astrophysical Journal. He has also authored an earlier paper which he believes shows the Universe to be about twice as old as the mainstream consensus believes it to be, so he can hardly be described as subscribing to some establishment orthodoxy. His work is explained in a University of Ottawa News release:

Saturday 16 March 2024

Why Religious People Find Atheism and Science Hard To Understand - Study Shows Atheists Are Generally More Intelligent Than Religious People


Why Are Religious People (Generally) Less Intelligent? | Psychology Today

One of the frustrating things about trying to debate with religious people in the social media, especially fundamentalists and creationists, is that they seem to have difficulty understanding simple logic such as the idea that the only reason for belief is evidence or the fact that lots of people believe something doesn't affect the truth of the belief.

There is also the impression (actually, it’s more than an impression, it seems to be a characteristic) that they think ignored evidence can be disregarded, so they will never read an article showing their beliefs to be wrong.

They generally seem more easily fooled by, for example, believing that an internet source supports them, when it is almost a rule that a link to a science paper provided by a fundamentalist will always say the opposite to what they claim it says, or that the ridiculous parody of science they've been fed by a creationist disinformation site such as AnswersInGenesis.com that no sane person would believe, is actually what real scientists believe. They have simply swallowed a lie and didn't see any need to check.

So, why do so many fundamentalists come across as limited in their ability to assimilate information and use it as the basis for opinions, other than an arrogant assumption that their beliefs must be true because they believe them, so no evidence is required and any contradictory evidence can be dismissed out of hand as 'wrong' or 'lies' or part of a giant conspiracy, and why do so many creationists came across as having the thinking ability of a toddler with a teleological view of the universe where even elementary particles are sentient and need to be told how to behave and which rules they must obey?

A meta-analysis of 63 earlier studies showed a statistically significant negative correlation between IQ and religiosity.

Friday 15 March 2024

Creationism in Crisis - From Where Did The Bible's Authors Get The Idea That Humans Are Materially Different To Other Animals? And Why Were They Wrong?


Greek vase decoration - Dionysus and three figures.(Gods created in human image)
Friday essay: from political bees to talking pigs – how ancient thinkers saw the human-animal divide

It's a fundamental part of the Abrahamic religions and other religions that there is something materially different to humans, above and beyond the sort of difference that distinguishes one species from another. Biologically, of course, this is nonsense as any study of comparative anatomy and physiology will show. Humans are just another mammal, albeit with some highly evolved abilities that other species lack such as language, the ability to invent narrative, etc. The differences, as with the differences between any pair of related taxons is quantitative, not qualitative.

So, from where did religions and, especially the Abrahamic religions - Judaism, Christianity and Islam - get the idea of human exceptionalism from and why did they need to invent narratives to explain it, usually in terms of a special creation or a special closeness to gods - even a familial relationship or at least created in their image like children to their parents? In fact, as we will see, it’s much more likely that gods were created by humans in their image.

In the following article, reprinted from The Conversation, Professor Julia Kindt, Department of Classics and Ancient History, University of Sydney, SNW, Australia, explains the ideas origins in Ancient Greece and why it is wrong. Her article has been reformatted for stylistic purposes:

Creationism in Crisis - Bird Watching In The Age Of Dinosaurs - About 70 Million Years Before 'Creation Week'


Archaeopteryx
Credit: Dotted Yeti/Shutterstock
A brief guide to birdwatching in the age of dinosaurs

What would it have been like to go bird-watching in that very long period of pre-'Creation Week' history just before a cataclysmic meteor strike cause the extinction of almost all the dinosaurs, 66 million years before creationists believe their god created a small, flat planet with a dome over it in the Middle-east?

At that time, Earth had a large population of dinosaurs, some of which were later to become modern birds which evolved to fill the vacated niches formerly occupied by the dinosaurs, while another survivor, a small rat-like early mammal, the descendant of mammal-like reptiles radiated into modern mammals.

For a period, these early birds, the avian dinosaurs which had evolved from the bipedal theropod dinosaurs, formed two major groups - the ornithuromorphs and the enantiornithine.

Thursday 14 March 2024

Creationism in Crisis - Rice Paddy Snakes In Thailand Diversified About 2.5 Million Years Before 'Creation Week'


Hypsiscopus murphyi sensu
Photo: Bryan Stuart
Rice paddy snake diversification was driven by geological and environmental factors in Thailand, molecular data suggests | KU News

In one of those far-away places that the simple-minded authors of the story in Genesis about a small flat Earth with a dome over it being magicked up out of nothing in the Middle East, 10,000 years ago, could never have guessed existed, and some 2.5 million years before they though Earth existed, major environmental changes were driving the diversification of a species of snake into several descendant species, just as the Theory of Evolution predicts.

If those simple-minded Bronze Age pastoralists had known about it and understood its significance in terms of the history of life on Earth and the dynamic geology of the planet, just imagine how different their imaginative tale would have been! As it was, they had to do their best with what little knowledge and understanding they had.

The snake in question was the Rice Paddy snake, otherwise known as a mud snake, and the far-away place was Thailand where the rise of the Khorat Plateau caused environmental changes that resulted in the evolutionary diversification of the Hypsiscopus genus.

The team of researchers from various American and Southeast Asian Universities, who have shown this link between environmental change and evolutionary radiation in a genus was led by Dr. Justin Bernstein, of the University of Kansas Center for Genomics. Their findings are published open access in Scientific Reports and are explained in a Kansas University news release:

Creationism in Crisis - Dinosaur Footprints In Alaska from 100 Million Years Before 'Creation Week'!


A theropod track lies in rock near the west bank of the Kukpowruk River.

Photo: Anthony Fiorillo
Alaska dinosaur tracks reveal a lush, wet environment | Geophysical Institute

About 100 million yearsd before creationism's god decided to create a small flat planet with a dome over it to keep the water about its sky out, there were dinosaurs living in what is now northern Alaska. The problem for creationists is that the people who wrote their favourite creation myths were ignorant both of dinosaurs and Alaska so had no idea their tales needed to include something about them, which is why everything they wrote about either happened within a day or two's walk if the Canaanite Hills or were plagiarized from nearby cultures.

Now a team of paleontologists and archaeologists have discovered fossilised dinosaur footprints and the remains of plants in the Nanushuk Formation that show the climate there was warmer and wetter than today, at a time when species were migrating over the landbridge between Siberia in Asia and North America.

Unlike the Paluxy hoax, which had creationists fooled for the best part of a decade, there were no human footprints (hand-carved or otherwise) associated with these dinosaur tracks.

Because creationists will try to falsify the aging of the Nanshuk Formation, claiming the method must have been flawed to such an extent that if made 10,000 years or less look like 100 million years, here is actually how the dating was done - it’s; those dreaded zircons in volcanic deposits again, plus stratigraphy based on index fossils found in rocks of known age:
Do you have any information on the Nanushuk Formation in northern Alaska and how its age was estimated? The Nanushuk Formation is a geological formation located in northern Alaska, particularly in the North Slope region. It is primarily composed of sandstone, siltstone, and shale, and it contains significant oil and gas reserves. The formation is of great interest to geologists and petroleum geologists due to its hydrocarbon potential.

The age of the Nanushuk Formation has been estimated through various methods, including biostratigraphy and radiometric dating of volcanic ash layers within the formation. Biostratigraphy involves the study of fossil assemblages found within the rocks to determine their relative ages. By comparing the fossils present in the Nanushuk Formation to those found in other formations with well-established ages, geologists can infer the approximate age of the Nanushuk Formation.

Additionally, radiometric dating techniques, such as radiocarbon dating or uranium-lead dating, can be used to determine the absolute ages of specific minerals or volcanic ash layers within the formation. These methods rely on the decay of radioactive isotopes within the rocks to estimate the time since their formation.

Through a combination of these techniques, geologists have estimated that the Nanushuk Formation was deposited during the Late Cretaceous period, approximately 70 to 80 million years ago. However, the precise age estimates may vary depending on the specific location within the formation and the methods used for dating.
The team, led by Dr. Anthony R. Fiorillo of the New Mexico Museum of Natural History & Science, Albuquerque, USA and including Professor Paul McCarthy of University of Alaska Fairbanks (UAF) College of Natural Science and Mathematics, have published their findings open access in the journal Geosciences. It is explained in a UAF news item:

Wednesday 13 March 2024

How Science Works - Giraffes - A single Pan-African Species Or Several Distinct Species?


Reticulated giraffe, Buffalo Springs, Kenya. Photo: Mogens Trolle

Photo: Mogens Trolle
Gene flow in giraffes and what it means for their conservation – Department of Biology - University of Copenhagen

In an evolutionary picture that resembles that of humans, giraffes appear to have speciated, or partially speciates at different times and in different parts of their range, then hybridized, before splitting again with regular gene-flow between the groups.

Similarly, though over a greater range, humans seems to have partially speciated into isolated populations in Africa before coming together again and spreading to Eurasia as Homo erectus which then split into Neanderthals, Denisovans and possibly others before meeting up with H. sapiens coming out of Africa in a second wave, to interbreed with the Eurasian species. The result is genetically distinct populations with evidence of ancient hybridization and gene flow.

Because conservation efforts tend to be directed at the species level, it is important for giraffe conservation to determine whether there is a single pan-African species with local sub-species or whether there are four or more species, each with a smaller population and therefore more vulnerable to habitat destruction and extinction.

To try to resolve this issue, as part of the African Wildlife Genomics research framework led by research groups at the Department of Biology at the University of Copenhagen, scientist carried out an extensive genome analysis to establish whether the different populations have been genetically isolated for long enough to be regarded as distinct species, even though, in captivity, they freely interbreed.

The results were a little surprising but highlight the difficulty in determining whether speciation has occurred within a population where differentiation is still in progress and few barriers to hybridisation have arisen. The problem is compounded by the fact that there is not a fixed definition of species, although biologists understand what the term means in a given context.

I've previously written blog posts about this problem, using the Eurasian crows as an example - an article incidentally which was recommended reading for Scottish biology students doing their 'Highers'.

The researchers have published their findings open access in the online Cell Press journal, Current Biology and explain it in a news item from the University of Copenhagen Biology Department:

Tuesday 12 March 2024

Malevolent Design - How The Malaria Parasite is 'Designed' To Evolve And Outwit Medical Science


The malaria parasite generates genetic diversity using an evolutionary ‘copy-paste’ tactic | EMBL

Devotees of creationism’s divine malevolence would be conflicted by this news if they understood it, because it shows the creative genius of any intelligent designer who could come up with this system, but, it looks like it did so (if you believe it couldn't happen naturally) by setting up an evolutionary process that creationists are obliged by dogma to believe doesn't work.

The news is that the organisms that causes malaria, Plasmodium falciparum, is 'designed' to quickly find a way to overcome the anti-malarial drugs medical science has developed to cure people suffering from it and to prevent others from getting malaria, by evolving very quickly.

The discovery was by researchers at European Molecular Biology Laboratory's (EMBL’s) European Bioinformatics Institute who have identified a mechanism of ‘copy-paste’ genetics that increases the genetic diversity of the parasite at accelerated time scales. This helps solve a long-standing mystery regarding why the parasite displays hotspots of genetic diversity in an otherwise unremarkable genetic landscape. Copy-paste' is a way of doing something creationists insist is impossible without the aid of god-magic of increasing the genetic information in a genome and making it available for evolution by mutation and selection without any loss of function in the original copied genes.

The team have recently published their finding in the open access journal PLOS Biology and describe it in an EMBL news item:

Unintelligent Malevolence - Pathogens 'Designed' to Beat Medical Science In Two Different Ways


Acinetobacter baumannii seen under a scanning electron-microscope

Escherichia coli
What makes a pathogen antibiotic-resistant? | Sanford Burnham Prebys

One of todays examples of the stupidity of creationism is something of a novelty. Usually, by applying the central tenets of creationism, any putative designer of living things like parasites either appears malevolent (and sometime it has to be said, malevolent at a near genius level in the ways it finds to make us and other animals sick) or it looks incompetent in that its 'solutions' are often to problems of its own making and more often than not to solutions it designed for one side of an arms race which it now trets as problems for the other side.

But today's example can only be described as an example of incompetent malevolennce, as creationism's putative designer, faced with the same 'problem' of medical science developing antibiotics effective against two different species of pathogen, set about designign two completely different 'solutions' to this problem. - Talk about re-inventing the wheel!

The pathogens are: Escherichia coli and Acinetobacter baumannii.

Creationists will probably be familiar with Escherichia coli (E. coli) because they believe their guru, Michael J Behe, 'proved' their god exists by claiming (falsely) that E. coli's flagellum must have been intelligently designed because he didn't know it evolved out of a pre-exiting structure and couldn't think how else it could have evolved. But then such is the standard of creationist apologetics!

What Behe had unwitting done was destroy the traditional excuse creationists use to explain pathogens like E. coli by blaming them on another 'designer' called 'Sin' which somehow creates living organisms although the creationit designer god is the only entitiy capable of designing livign things, so any example of 'intelligent design, real or imaginary, if 'proof' of this designer god's existance.

So, what creationists are now left with is an E.coli with a flegellum designed by their god to make it better at making us sick, and now resitant to antibiotics to help it win against medical science trying to prevent it makign us sick!

But what creationists are less likely to be familiar with is the pathogen, Acinetobacter baumannii, so here is a little background:

Monday 11 March 2024

Unintelligent Design - RuBisCO Is Slowly Evolving - And Becoming Even More Embarrassing For Any Creationist Who Understands It


The world’s most prolific CO2-fixing enzyme is slowly getting better | University of Oxford

The world’s worst enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase, or RuBisCo as it is known, has featured in these blog posts several times and it described in my book, The Unintelligent Designer: Refuting the Intelligent Design Hoax as an example of the lack of intelligence in biological systems, and, as such, why it would be a major embarrassment to creationists - if they understood it.

Briefly, RuBisCo is one of the most ancient enzymes known and became an essential component of photosynthesis early on in the history of life on Earth when the first cyanobacteria evolved the ability to use the energy from sunlight to fix the carbon in atmospheric carbon dioxide (CO2) to build the sugar glucose. Eventually, these photosynthesising cyanobacteria became incorporated into plant cells as the chloroplasts to produce the green plants at the base of most food chains. Because it is so inefficient, it quickly became probably the most abundant enzyme on Earth, making up with quantity what it lacked in quality.

But, evolution, unlike good intelligent design, is a one-way, utilitarian process in which whatever works better than preceded it will be retained and will provide the next basis for further evolution, because evolution has no mechanism to scrap a bad design and start again as any backward step will inevitably be worse, so will be quickly eliminated.
Tell me all about RuBisCo and why it's so inefficient. RuBisCo, or ribulose-1,5-bisphosphate carboxylase/oxygenase, is an enzyme crucial for the process of carbon fixation in plants, algae, and some bacteria. It catalyzes the first major step of the Calvin cycle, which is the primary pathway for carbon dioxide fixation in photosynthesis. Despite its importance, RuBisCo is often considered inefficient for several reasons:

Malevolent Design - How a Bacterium Carries a Virus That Selectively Kills Male Insects And Only Allows Infected Females To Breed


How does a virus hijack insect sperm to control disease vectors and pests? | Penn State University

Wolbachia are a genus of bacteria that form a symbiotic relationship with about 50% of arthropod species, including insects and spiders but they can also manipulate the species for their own ends (in terms of breeding success). They are aided in this by a virus which is incorporated in their genome which has been shown to join forces with Wolbachia to ensure their own reproductive success in the form of females infected with the virus-bearing Wolbachia.

So completely have Wolbachia integrated with insects that one species of fruit fly has the entire Wolbachia genome incorporated into its own genome, making it, biologically, both bacterium and fruit fly.

One way Wolbachia ensure their own survival at the expense of the species of insect they infect is by making the sperm and egg incompatible if the female is not also a carrier of the right species of Wolbachia. And, to be on the safe side, two proteins produced by the virus break the sperm's DNA so any resulting embryo will be defective and will fail to develop. This ensures that only the females carrying the infection can breed, so increasing the Wolbachia and its virus in the gene pool.

The team who discovered this nasty little virus and how it acts selfishly, was co-led by Professor Seth R. Bordenstein, of the One Health Microbiome Center at Pennsylvania State University. They have published their findings in Science and described it in a Penn State News item.

But first, a little background on Wolbachia:

Sunday 10 March 2024

Unintelligent Design - How Epigenetic Settings Are Passed To Daughter Cells - Even William Heath Robinson Would Be Impressed


Cracking Epigenetic Inheritance: HKU Biologists Discovered the Secrets of How Gene Traits are Passed on - Press Releases - Media - HKU

It all started when single-celled organisms started to form colonies of like-minded individuals. The easiest way to do it was for the two daughter cells of a dividing cell to stick together instead of going their own way. They in turn would have had more daughter cells until they formed large clump of cells, but, unless the cells began to perform distinct functions, there was no advantage to forming clumps like that instead of each cell going its own way and fending for itself. Fortunately, there were no large predators around, otherwise a clump of cells would have made a tasty snack and the whole idea would have been abandoned as too risky by half, and we would be stuck now with a world of single-celled organisms and nothing else.

However, with the trial and error which characterises biological development, some of the cells in the clump began to perform specialist functions. For example, as the clump got larger, specialist cells would have been needed to exchange gasses with the environment or the cells at the centre would have been deprived of oxygen and their waste in the form of carbon dioxide would have accumulated because diffusing across a large mass of cells would be too slow to keep up with production and the supply of oxygen would be too slow to keep up with the demand. The same thing applied to getting nutrients into the center of the clump.

So, the clumps which had specialist cells fared better in the competition for resources than those which were just undifferentiated clumps. In fact, the clumps with specialised cells would probably have eaten the undifferentiated clumps and become predators. And with predators there was pressure for increased specialisation for movement, ingestion and excretion, for more efficient respiration and for reproduction. And predation also produced pressure for more motility, for senses like sight and smell and maybe hearing and as the organisms became more complex so they needed nervous systems to coordinate their activities and process and respond to the stimuli their senses were receiving from their environment and some would have evolved defensive armour such as scales and spikes and hard shells and internal structures like cartilage and bone to give their bodies shape and form and to make their swimming apparatus stiffer and more powerful.

But what they never managed to do was find a different way to produce all the different specialist cells by a different method to that used by their single-celled ancestors, so every cell in their body had the full genome whether they needed it or not, and more often than not, they didn't need most of it. A bone cell doesn't need to do what a nerve cell does, and a nerve cell doesn't need to do what a muscle cell does, and neither muscle nor nerve cells need to make bone, and what else needs to make elbow skin other than an elbow skin cell, except perhaps a scrotum skin cell? Yet they all have the genes for doing everything any one cell needs to do.

So, cue creationism's intelligent [sic] designer who has been designing and modifying all these different clumps of specialised cells but who, for some reason, seems incapable of recognising that its designs are heading for disaster unless it can think up a way to make sure each specialised cell has only the genes it needs. For reasons which no creationist apologist has ever managed to explain, their putative designer always behaves as though it can't undo a bad design and start again but is compelled to try to make the best of what it has muddled through with so far. In every way, creationism’s 'intelligent [sic] designer' behaves just like a mindless process operating without a plan, handicapped by acute amnesia, and constantly surprising itself with a new problem it designed just yesterday.

Just like the eccentric British designer and cartoonist, William Heath Robinson, no solution to a problem can be too complex even if it creates a new problem for which another overly complex solution has to be found. Unlikely objects, designed for a completely different purpose, will be pressed into service; a stepladder will be balanced precariously on top of a piano and an umbrella will be used to push a button when prodded by a sink plunger swinging on a length of knotted string. A labour-saving device for peeling potatoes will take half a dozen, intense and serious-looking men to operate it and peeling the potatoes will take considerably longer than had each man been given a potato peeler and left to get on with it. Eggs will be fried in a frying pan held over a candle lit by a match rubbed against a matchbox which swings into action when released by a lever when the scuttle-full of coal, or the boulder suspended on knotted string, lands on it.
Every hot-air ballon will have had several leaks mended with patches in a different fabric as will every set of bellows used to blow out the candle at the right time or make the fire burn up when needed to make the hot air balloon rise, which will be held down by a coal-scuttle full of coal until a man with nothing else to do, cuts the string with a pair of scissors when prodded in the back by an umbrella operated by a wheel with broken spokes joined together with sticks tied on with more string or held together with bent nails.

And the whole 'irreducibly complex', 'intelligently designed' machine would fail if just one component was taken away or a piece of knotted string broke.
So, what did creationism's intelligent designer produce to solve the problem of too many genes for the specialised cells? It produced the overly complex solution of epigenetics of course! There was no going back and starting again for our intrepid, muddle through, mend and make do, near-enough-is-good-enough utilitarian designer. Going back and starting again would have been far too simple.

So complex is this system, that a team of researchers has only just worked out how cells pass on their epigenetic settings to their daughter cells.

Their findings are the subject of a paper in Nature and a news release from the University of Hong Kong:

Figure 2.The cryo-EM structure of the yeast replisome in complex with FACT and parental histones (A) and its atomic model (B).
Modified from Li et al, Nature (2004)
Figure 2. The cryo-EM structure of the yeast replisome in complex with FACT and parental histones (A) and its atomic model (B).
Modified from Li et al, Nature (2004)
A research team led by Professor Yuanliang ZHAI at the School of Biological Sciences, The University of Hong Kong (HKU) collaborating with Professor Ning GAO and Professor Qing LI from Peking University (PKU), as well as Professor Bik-Kwoon TYE from Cornell University, has recently made a significant breakthrough in understanding how the DNA copying machine helps pass on epigenetic information to maintain gene traits at each cell division. Understanding how this coupled mechanism could lead to new treatments for cancer and other epigenetic diseases by targeting specific changes in gene activity. Their findings have recently been published in Nature.

Background of the Research

Our bodies are composed of many differentiated cell types. Genetic information is stored within our DNA which serves as a blueprint guiding the functions and development of our cells. However, not all parts of our DNA are active at all times. In fact, every cell type in our body contains the same DNA, but only specific portions are active, leading to distinct cellular functions. For example, identical twins share nearly identical genetic material but exhibit variations in physical characteristics, behaviours and disease susceptibility due to the influence of epigenetics. Epigenetics functions as a set of molecular switches that can turn genes on or off without altering the DNA sequence. These switches are influenced by various environmental factors, such as nutrition, stress, lifestyle, and environmental exposures.

In our cells, DNA is organised into chromatin. The nucleosome forms a fundamental repeating unit of chromatin. Each nucleosome consists of approximately 147 base pairs of DNA wrapped around a histone octamer which is composed of two H2A-H2B dimers and one H3-H4 tetramer. During DNA replication, parental nucleosomes carrying the epigenetic tags, also known as histone modifications, are dismantled and recycled, ensuring the accurate transfer of epigenetic information to new cells during cell division. Errors in this process can alter the epigenetic landscape, gene expression and cell identity, with potential implications for cancer and ageing. Despite extensive research, the molecular mechanism by which epigenetic information is passed down through the DNA copying machine, called the replisome, remains unclear. This knowledge gap is primarily due to the absence of detailed structures that capture the replisome in action when transferring parental histones with epigenetic tags. Studying the process is challenging because of the fast-paced nature of chromatin replication, as it involves rapid disruption and restoration of nucleosomes to keep up with the swift DNA synthesis.

In previous studies, the research team made significant progress in understanding the DNA copying mechanism, including determining the structures of various replication complexes. These findings laid a solid foundation for the current research on the dynamic process of chromatin duplication.

Summary of Research Findings

This time, the team achieved another breakthrough by successfully capturing a key snapshot of parental histone transfer at the replication fork. They purified endogenous replisome complexes from early-S-phase yeast cells on a large scale and utilised cryo-electron microscopy (cryo-EM) for visualisation.

They found that a chaperone complex FACT (consisting of Spt16 and Pob3) interacts with parental histones at the front of the replisome during the replication process. Notably, they observed that Spt16, a component of FACT, captures the histones that have been completely stripped off the duplex DNA from the parental nucleosome. The evicted histones are preserved as a hexamer, with one H2A-H2B dimer missing. Another protein that involved in DNA replication, Mcm2, takes the place of the missing H2A-H2B dimer on the vacant site of the parental histones, placing the FACT-histone complex onto the front bumper of the replisome engine, called Tof1. This strategic positioning of histone hexamer on Tof1 by Mcm2 facilitates the subsequent transfer of parental histones to the newly synthesised DNA strands. These findings provide crucial insights into the mechanism that regulates parental histone recycling by the replisome to ensure the faithful propagation of epigenetic information at each cell division.

This study, led by Professor Zhai, involved a collaborative effort that spanned nearly eight years, starting at HKUST and concluding at HKU. He expressed his excitement about the findings, ‘It only took us less than four months from submission to Nature magazine to the acceptance of our manuscript. The results are incredibly beautiful. Our cryo-EM structures offer the first visual glimpse into how the DNA copying machine and FACT collaborate to transfer parental histone at the replication fork during DNA replication. This knowledge is crucial for elucidating how epigenetic information is faithfully maintained and passed on to subsequent generations. But, there is still much to learn. As we venture into uncharted territory, each new development in this field will represent a big step forward for the study of epigenetic inheritance.’

The implications of this research extend beyond understanding epigenetic inheritance. Scientists can now explore gene expression regulation, development, and disease with greater depth. Moreover, this breakthrough opens up possibilities for targeted therapeutic interventions and innovative strategies to modulate epigenetic modifications for cancer treatment. As the scientific community delves deeper into the world of epigenetics, this study represents a major step towards unravelling the complexities of replication-coupled histone recycling.

About the Research Team

Apart from Professor Yuanliang Zhai’s lab, the research team also includes Professor Xiang David Li from Department of Chemistry of HKU, Professor Yang Liu and Professor Keda Zhou from School of Biomedical Sciences of HKU, Professor Shangyu Dang from Division of Life Science of HKUST, and others. Learn more about Professor Yuanliang Zhai’s work and his research team: https://www.scifac.hku.hk/people/zhai-yuanliang or https://zhai95.wixsite.com/mysite-1

Co-authors include Mr Yuan Gao, Mr Jian Li, Dr Zhichun Xu from School of Biological Sciences (SBS) of HKU; Dr Ningning Li, Ms Yujie Zhang, Dr Jianxun Feng from School of Life Sciences of PKU, Dr Daqi Yu and Dr Jianwei Lin from Department of Chemistry of HKU, and Dr Yingyi ZHANG from Biological Cryo- EM Center of HKUST.

The journal paper can be accessed here: https://www.nature.com/articles/s41586-024-07152-2

Abstract

In eukaryotes, DNA compacts into chromatin through nucleosomes1,2. Replication of the eukaryotic genome must be coupled to the transmission of the epigenome encoded in the chromatin3,4. Here we report cryo-electron microscopy structures of yeast (Saccharomyces cerevisiae) replisomes associated with the FACT (facilitates chromatin transactions) complex (comprising Spt16 and Pob3) and an evicted histone hexamer. In these structures, FACT is positioned at the front end of the replisome by engaging with the parental DNA duplex to capture the histones through the middle domain and the acidic carboxyl-terminal domain of Spt16. The H2A–H2B dimer chaperoned by the carboxyl-terminal domain of Spt16 is stably tethered to the H3–H4 tetramer, while the vacant H2A–H2B site is occupied by the histone-binding domain of Mcm2. The Mcm2 histone-binding domain wraps around the DNA-binding surface of one H3–H4 dimer and extends across the tetramerization interface of the H3–H4 tetramer to the binding site of Spt16 middle domain before becoming disordered. This arrangement leaves the remaining DNA-binding surface of the other H3–H4 dimer exposed to additional interactions for further processing. The Mcm2 histone-binding domain and its downstream linker region are nested on top of Tof1, relocating the parental histones to the replisome front for transfer to the newly synthesized lagging-strand DNA. Our findings offer crucial structural insights into the mechanism of replication-coupled histone recycling for maintaining epigenetic inheritance.

This Heath-Robinson solution to a problem which no intelligent designer would design in the first place, is repeated in every one of your 17 trillion cells and in every cell of every multicellular organism on the planet. A hugely wasteful and error-prone, needlessly complex system of which any intelligent designer would be ashamed, but which creationist frauds fool their ignorant dupes into believing is evidence of intelligence. In reality of course, it's evidence of exactly the opposite.

It's not even humorous and entertaining like William Heath-Robinson's ridiculously complicated, irreducibly complex, machines.

Covidiot News - Just Because You Haven't Had COVID-19 Yet, Doesn't Mean You Won't!


Haven't had COVID yet? It could be more than just luck

There are some scary questions for creationists at the end of this article. They follow on naturally from what's being discussed, so creationists should probably avoid reading too far, unless they have a responsible adult with them.

This article from The Conversation is from May 2022, when we were into the second year of the COVID-19 pandemic and most vulnerable people had had the two-step vaccinations and many would have had the spring booster. At that point neither me nor my partner had had COVID-19, which we put down to rigorously following the recommendations regarding mask-wearing, social distancing, hand washing, etc. and had tried to reduce our vulnerability to the sever forms of it by losing about 3 stone in weight and, in my case, getting my blood pressure under control with medication. We also tried to ensure our immune systems were healthy by taking vitamin D3, vitamin C, zinc and iron supplements.

In the early days of the pandemic, even before the official restrictions on social contact, we had observed the basic rules of hygiene and everyone who came into the house used hand-cleanser at the front door. I had even managed to obtain a supply of face-masks and plastic gloves online, which we wore at all times outside the house. Every package that was delivered to the house was left for several hours before we touched it, and all our weekly shopping was delivered or bought with click and collect. Delivered bags were left for four hours before unpacking. And we took weekly tests just in case we had it asymptomatically. All that might seem a little over the top now, but we were vindicated as events were to prove.

We put the fact that we hadn't caught it by mid-2022 down to our preventative measures, not to luck or genetics - a view that was vindicated last year when we both came back from a two-week vacation in France with a mild form of COVID-19, despite having had all the boosters on offer. We probably picked it up in a crowded airport or on the plane, where all the social distancing measures had been forgotten and even face masks were no longer worn. We both felt like we had a mild case of flu for a couple of days and after a week we were testing negative. Had we contracted it in Spring 2020, the outcome would probably have been very different as we had no immunity, and both had three of the risk-factors - overweight, high BP and over 70. In addition, my partner had had a mastectomy and was receiving treatment for breast cancer.

One reason you can't ever be sure that you won't catch COVID-19 is because the virus keeps mutating to produce new variants so, even if you were fortunate enough to have natural or acquired immunity to the variants so far, it is quite possible that the next or subsequent variants will have evolved a way round it. The following chart from the UK NHS, shows the rise and fall of the main variants over the course of the pandemic:
But still, a few people managed to stay free from the virus. In the following article, reprinted from The Conversation under a Creative Commons license, Lindsay Broadbent, Research Fellow, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, explains why. Her article has been reformatted for stylistic consistency:

Saturday 9 March 2024

Creationism in Crisis - Geobiologists Discover The Cause of Earth's First Mass Extinctions Event - 550 Million Years Before 'Creation Week'


Impressions of the Ediacaran fossils Dickinsonia (at center) with the smaller anchor shaped Parvancorina (left) in sandstone of the Ediacara Member from the Nilpena Ediacara National Park in South Australia.
Photo: Scott Evans.
Geobiologists shine new light on Earth’s first known mass extinction event 550 million years ago | VTx | Virginia Tech

A big problem for Creationists, especially those who believe the Bible was written by an infallible creator god, so think Earth is just a few thousand years old, is that science keeps finding evidence that Earth is billions of years old, and finding fossils of the life-forms that were around then.

As though that wasn't refutation enough, a team of scientists from Virginia Tech have now explained the mass extinction that wiped out most of these early life forms several billion years ago - giving the lie that they were intelligently designed by a god with the ability of foresight. Such a god would have known about the future mass extinctions and either prevented it, designed his creations to survive it or at least waited till it was safe to create things. Creating things to go extinct is not the act of an intelligent or sane creator.

This mass extinction appears not to have been a sudden event, such as that that resulted in the extinction of the non-avian dinosaurs and large marine reptile predators, but to have occurred in two phases that resulted in a loss of about 80% of species and separated by about 10 million years.

But before creationists get over-excited, this does not mean all the Ediacarans were extinct at the Cambrian 'explosion' so the Cambrian biota had no ancestors. It means that there were still about 20% of the Ediacaran biota to evolve over the 6 million years of the Cambrian 'explosion' into the Cambrian biota.

The Ediacaran mass extinction was probably caused by falling Oxygen levels as Ediacarans that had evolved large mass to surface-area ratios suffered from a loss of oxygen more so than those which had retained a smaller mass to surface area ratio.

How this mass extinction was identified and related to changes in global oxygen levels was the subject of an open access paper in PNAS and a Virginal Tech News item:
A new study by Virginia Tech geobiologists traces the cause of the first known mass extinction of animals to decreased global oxygen availability, leading to the loss of a majority of animals present near the end of the Ediacaran Period some 550 million years ago.

The research spearheaded by Scott Evans, a postdoctoral researcher in the Department of Geosciences, part of the Virginia Tech College of Science, shows this earliest mass extinction of about 80 percent of animals across this interval.

This included the loss of many different types of animals, however those whose body plans and behaviors indicate that they relied on significant amounts of oxygen seem to have been hit particularly hard. This suggests that the extinction event was environmentally controlled, as are all other mass extinctions in the geologic record.

Dr Scott D. Evans, lead author
Department of Geosciences
Virginia Tech, Blacksburg, VA, USA
Evans’ work was published today [7 November 2022] in the Proceedings of the National Academy of Sciences, a peer-reviewed journal of the National Academy of Sciences. The study was co-authored by Shuhai Xiao, also a professor in the Department of Geosciences, and several researchers led by Mary Droser from the University of California Riverside’s Department of Earth and Planetary Sciences, where Evans earned his master’s degree and Ph.D.

Environmental changes, such as global warming and deoxygenation events, can lead to massive extinction of animals and profound disruption and reorganization of the ecosystem. This has been demonstrated repeatedly in the study of Earth history, including this work on the first extinction documented in the fossil record. This study thus informs us about the long-term impact of current environmental changes on the biosphere.

Shuhai Xiao, co-author
Department of Geosciences
Virginia Tech, Blacksburg, VA, USA.

[What exactly caused the drop in global oxygen?] The short answer to how this happened is we don't really know. It could be any number and combination of volcanic eruptions, tectonic plate motion, an asteroid impact, etc., but what we see is that the animals that go extinct seem to be responding to decreased global oxygen availability.

Dr Scott D. Evans
The study by Evans and Xiao is timelier than one would think. In an unconnected study, Virginia Tech scientists recently found that anoxia, the loss of oxygen availability, is affecting the world’s fresh waters. The cause? The warming of waters brought on by climate change and excess pollutant runoff from land use. Warming waters diminish fresh water’s capacity to hold oxygen, while the breakdown of nutrients in runoff by freshwater microbes gobbles up oxygen.

Our study shows that, as with all other mass extinctions in Earth's past, this new, first mass extinction of animals was caused by major climate change — another in a long list of cautionary tales demonstrating the dangers of our current climate crisis for animal life/

Dr Scott D. Evans
Some perspective: The Ediacaran Period spanned roughly 96 million years, bookended on either side by the end of Cryogenian Period — 635 million years ago — and the beginning of the Cambrian Period — 539 million years ago. The extinction event comes just before a significant break in the geologic record, from the Proterozoic Eon to the Phanerozoic Eon.

There are five known mass extinctions that stand out in the history of animals, the “Big Five,” according to Xiao, including the Ordovician-Silurian Extinction (440 million years ago), the late Devonian Extinction (370 million years ago), the Permian-Triassic Extinction (250 million years ago), the Triassic-Jurassic Extinction (200 million years ago), and the Cretaceous-Paleogene Extinction (65 million years ago).

Impressions of the Ediacaran fossils Dickinsonia (at left) and related but rare form Andiva (at right) in sandstone of the Ediacara Member from the Nilpena Ediacara National Park in South Australia.
Photo courtesy of Scott Evans.

“Mass extinctions are well recognized as significant steps in the evolutionary trajectory of life on this planet,” Evans and team wrote in the study. Whatever the instigating cause of the mass extinction, the result was multiple major shifts in environmental conditions. “Particularly, we find support for decreased global oxygen availability as the mechanism responsible for this extinction. This suggests that abiotic controls have had significant impacts on diversity patterns throughout the more than 570 million-year history of animals on this planet,” the authors wrote.

Fossil imprints in rock tell researchers how the creatures that perished in this extinction event would have looked. And they looked, in Evans’ words, “weird.”

These organisms occur so early in the evolutionary history of animals that in many cases they appear to be experimenting with different ways to build large, sometimes mobile, multicellular bodies. There are lots of ways to recreate how they look, but the take-home is that before this extinction the fossils we find don't often fit nicely into the ways we classify animals today. Essentially, this extinction may have helped pave the way for the evolution of animals as we know them.

Dr Scott D. Evans
The study, like scores of other recent publications, came out of the COVID-19 pandemic. Because Evans, Xiao, and their team couldn't get access to the field, they decided to put together a global database based mostly on published records to test ideas about changing diversity. “Others had suggested that there might be an extinction at this time, but there was a lot of speculation. So we decided to put together everything we could to try and test those ideas.” Evans said. Much of the data used in the study was collected by Droser and several graduate students from the University of California Riverside.
Impressions of the Ediacaran fossil Dickinsonia, one of the first mobile animals, in sandstone of the Ediacara Member from the Nilpena Ediacara National Park in South Australia.">
Photo courtesy of Scott Evans.
Technical details is in the team's open access paper on PNAS:
Significance
Mass extinctions are well recognized as significant steps in the evolutionary trajectory of life on this planet. Here, we document the oldest known extinction of animals and test for potential causes. Our results indicate that, like younger diversity crises, this event was caused by major shifts in environmental conditions. Particularly, we find support for decreased global oxygen availability as the mechanism responsible for this extinction. This suggests that abiotic controls have had significant impacts on diversity patterns throughout the more than 570-My history of animals on this planet.

Abstract

The Ediacara Biota—the oldest communities of complex, macroscopic fossils—consists of three temporally distinct assemblages: the Avalon (ca. 575–560 Ma), White Sea (ca. 560–550 Ma), and Nama (ca. 550–539 Ma). Generic diversity varies among assemblages, with a notable decline at the transition from White Sea to Nama. Preservation and sampling biases, biotic replacement, and environmental perturbation have been proposed as potential mechanisms for this drop in diversity. Here, we compile a global database of the Ediacara Biota, specifically targeting taphonomic and paleoecological characters, to test these hypotheses. Major ecological shifts in feeding mode, life habit, and tiering level accompany an increase in generic richness between the Avalon and White Sea assemblages. We find that ∼80% of White Sea taxa are absent from the Nama interval, comparable to loss during Phanerozoic mass extinctions. The paleolatitudes, depositional environments, and preservational modes that characterize the White Sea assemblage are well represented in the Nama, indicating that this decline is not the result of sampling bias. Counter to expectations of the biotic replacement model, there are minimal ecological differences between these two assemblages. However, taxa that disappear exhibit a variety of morphological and behavioral characters consistent with an environmentally driven extinction event. The preferential survival of taxa with high surface area relative to volume may suggest that this was related to reduced global oceanic oxygen availability. Thus, our data support a link between Ediacaran biotic turnover and environmental change, similar to other major mass extinctions in the geologic record.

Soft-bodied fossils of the Ediacara Biota comprise the oldest communities of macroscopic organisms, including animals, and are critical for understanding the advent and diversification of complex life (1, 2). However, equally important are the dynamics that lead to the disappearance of such animals (36). Two major drops in diversity of the Ediacara Biota have been recognized, an initial decrease between the White Sea and Nama assemblages and a second across the Ediacaran–Cambrian boundary (Fig. 1 and ref. (5)). Although these events may be related, they are separated by more than 10 My and vary in magnitude and taxa impacted. The exceptional conditions required to preserve the Ediacara Biota also leave uncertainty around potential taphonomic biases that may contribute to such patterns. Diversity crises shaped the course of evolution in the Phanerozoic. Thus, a comprehensive understanding of each of these Ediacaran events is critical to determine the fate of Earth’s early animals.
Raw generic diversity (black squares), bootstrapped diversity (gray triangles), bootstrapped (42) per taxon extinction rate (solid blue), and origination rate (dashed green). Error bars represent 1 SD. For bootstrapping analysis, database occurrences were randomly subsampled to 50 occurrences.
M
Similar mechanisms have been proposed for losses of diversity during both the White Sea–Nama and Ediacaran–Cambrian transitions. One suggestion is that taxa did not go extinct but instead are not preserved in subsequent intervals (the “Cheshire cat” model of ref. (3)). Biases may include differences in the paleolatitudes and paleoenvironments sampled as well as variable taphonomic windows preserving fossils from each assemblage (7). Alternatively, these events may represent true extinctions triggered by either biotic or abiotic factors or some combination thereof (3, 5). The biotic replacement model, generally attributing the demise of the Ediacara Biota to competition with more advanced “Cambrian-style” metazoans, focuses on the impact of bioturbators as indicated by increases in trace fossil diversity (e.g., ref. (8)). Such ecosystem engineers are proposed to have fundamentally changed carbon packaging and fluid transport in the latest Ediacaran (3, 4, 810). Alternatively, the catastrophic extinction model posits that a major environmental perturbation led to the rapid loss of a variety of Ediacara taxa (3, 5) supported by geochemical data for environmental conditions, such as changes in oxygen availability (e.g., ref. (11)).


Here, we use a holistic approach, combining the distribution, taphonomy, and ecology of constituent taxa, to investigate changes in the Ediacara Biota through compilation of global occurrence data. Specifically, we test for potential sampling biases in the form of major differences in the paleolatitudes, facies associations, or preservational modes that could account for apparent changes in taxonomic composition. Based on the lack of correlation between these factors, we then investigate paleoecological trends through the Ediacaran under the assumption that, as with other diversity crises in the fossil record (12), patterns of selectivity across these intervals should reflect the factors responsible for such change. Analysis was conducted by comparing differences between the three assemblages—necessarily representing time-averaged groups of organisms on the order of millions to tens of millions of years—as in previous studies (e.g., refs. (3, 5, 13)). However, we also examined patterns of change involving taxa that survived and went extinct at the end of the White Sea assemblage to investigate changes on relatively shorter geologic timescales.
Fig. 2. Paleogeographic distribution of fossil localities (A) within the three assemblages of the Ediacara Biota based on continental configurations by Merdith et al. (14) and pie charts with the distribution of paleoenvironments (B) and modes of preservation (C) sampled for each assemblage, with “n” referring to the No. of formations/facies sampled in each time bin. See SI Appendix, Fig. S1 for locality labels.
Mass extinctions alone are enough to refute the childish notion of creation by an omniscient designer, let alone an intelligent one, and of course one reason the Ediacaran biota doesn't get a mention in the Bible is because, like all the other extinct taxons, the primitive Bronze Age authors had not got the slightest idea that they ever existed or that Earth was old enough to have gone through several major geological era lasting hundreds of millions of years, and several mass extinctions which had wiped out most of the earlier species or they wouldn't have assumed everything was magically created as it was then, But then they only had what little knowledge their culture possessed out of which to concoct a believable story.

Creationism in Crisis - Earth's Oldest Forest Was In Present-Day Dorset, UK - 390 Million Years Before Creationism's 'Creation Week'


Cliffs of the Hangman Sandstone Formation, where many of the fossils were found.
Credit: Neil Davies
Earth’s earliest forest revealed in Somerset fossils

Archaeologists have found what are believed to be the remains of the earliest forest so far discovered in Devonian sandstone rocks dated to 390 million years ago, which makes them 4 million years older than the previous record found in New York State, and means they were living almost 390 million years before creationism's 'Creation Week' when their god decided to create a small flat planet with a dome over it, centered on the Middle East.

The fossils were discovered in coastal cliffs near Minehead, Dorset, England in what is known as the Eifelian Hangman Sandstone Formation and consist of primitive trees which were ancestral to today's trees but looked more like palm trees. The discovery is the subject of a paper in the Journal of the Geological Society and a news release from the University of Cambridge, UK.

First a little about this rock formation:
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