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

Thursday 28 March 2024

Malevolent Designer - How Creationism's Putative Designer COULD Have Given Us A Mechanism to Prevent Heart Attacks But Chose Not To


Naked mole rats, Heterocephalus glaber - uniquely able to resist cardiac damage.
FMD - Secrets of the naked mole-rat: new study reveals how their unique metabolism protects them from heart attacks - Queen Mary University of London

Part of creationists mythology is the belief that humans stand at the pinnacle of creation, being the supreme creation of their putative designer. Even those who accept the evidence for evolution, like to imagine that somehow evolution was intended to result in humans being at the apex of it.

As you would expect of creationism, those beliefs are counter-factual and so are not supported by the evidence, and, if they are to be believed, paints their putative creator god in a very poor light, not the least because of the very many examples of where, if it had created humans and all the other species, humans come off at best second best, having inferior versions of organs and processes compared to many other species. I list several of these in my popular, illustrated book, The Malevolent Designer: Why Nature's God is not Good, for example, the superior eye of the peregrine falcon, the superior immune system of bats and the fact that elephants and sharks rarely get cancer.
Now we have the example of naked mole rats which are able to suffer anoxia without sustaining damage to their cardiac muscles, so they rarely have heart attacks.

The damage during a heart attack, i.e., when a cardiac artery is blocked by a blood clot, is cell death due to being deprived of oxygen. But Naked mole rats have a unique cardiac metabolism and unique genes, that enable their cardiac muscle cells to survive a period of anoxia.

The reason for this, and the mechanism creationism's creative god could have given humans if it were real and is as omnibenevolent as creationists like to pretend, was discovered by researchers from London, Pretoria and Cambridge, led by Dr. Dunja Aksentijevic of the Centre for Biochemical Pharmacology, William Harvey Research Institute, Bart’s and the London Faculty of Medicine and Dentistry, Queen Mary University of London, London, UK.

The team have just published their findings, open access, in the journal Nature Communications. It is also explained in a Queen Mary University news release:

Creationism in Crisis - 4,000 Year-Old Human Teeth From Ireland Show No Signs Of The legendary Biblical Flood - But Every Sign of Evolution


Killuragh Cave, County Limerick, Ireland.
Photo: Sam Moore; Owner: Marion Dowd.
Genetic secrets from 4,000-year-old teeth to illuminate the impact of changing human diets over the centuries - News & Events | Trinity College Dublin

What can you tell from two, 4000-year-old human teeth found in a limestone cave in Ireland?

Firstly, you can tell a great deal about the food their owner ate and what state their oral hygiene was in.

Secondly, you can tell how the microbiome of the human mouth has evolved over the last 4000 years.

Thirdly, you can tell that, wherever creationism's global flood took place, it missed this cave in Ireland, because had the cave been flooded, the remains of bacterial DNA in the plaque on the teeth would have been washed off, even in the unlikely event of the skeletal remains staying in the cave.

And lastly, you can tell the cave is very much older than the 10,000 years creationists believe Earth has existed for because limestone caves form slowly over millions of years due to the action of water on limestone deposits that themselves take millions of years to accumulate and be compressed into limestone.

But then the ignorant goat-herders who invented the mythical global flood knew nothing of limestone cave formation, Ireland, the people who lived there, the state of their oral hygiene, or micro-organisms for that matter, so what did you expect? Miracles?

The two teeth, from the same individual, were part of a large skeletal assemblage excavated from Killuragh Cave, County Limerick, by the late Peter Woodman of University College Cork. They have been used by researchers from Trinity College, Dublin to recover a remarkably well-preserved microbiome which shows major changes in the oral microenvironment from the Bronze Age to today.

The researchers, led by Dr Lara Cassidy, an assistant professor in Trinity’s School of Genetics and Microbiology and including scientists from the Atlantic Technological University and University of Edinburgh, have published their findings, open access in the journal Molecular Biology and Evolution and describe them in a Trinity College News release:
Researchers from Trinity have recovered remarkably preserved microbiomes from two teeth dating back 4,000 years, found in an Irish limestone cave. Genetic analyses of these microbiomes reveal major changes in the oral microenvironment from the Bronze Age to today.

The teeth both belonged to the same male individual and also provided a snapshot of his oral health.

The study, carried out in collaboration with archaeologists from the Atlantic Technological University and University of Edinburgh, was published today in leading journal Molecular Biology and Evolution.

The authors identified several bacteria linked to gum disease and provided the first high-quality ancient genome of Streptococcus mutans, the major culprit behind tooth decay.

While S. mutans is very common in modern mouths, it is exceptionally rare in the ancient genomic record. One reason for this may be the acid-producing nature of the species. This acid decays the tooth, but also destroys DNA and stops plaque from fossilising. While most ancient oral microbiomes are retrieved from fossilised plaque, this study targeted the tooth directly.

Another reason for the scarcity of S. mutans in ancient mouths may be the lack of favorable habitats for this sugar-loving species. An uptick of dental cavities is seen in the archaeological record after the adoption of cereal agriculture thousands of years ago, but a far more dramatic increase has occurred only in the past few hundred years when sugary foods were introduced to the masses.

The sampled teeth were part of a larger skeletal assemblage excavated from Killuragh Cave, County Limerick, by the late Peter Woodman of University College Cork.

While other teeth in the cave showed advanced dental decay, no cavities were visible on the sampled teeth. However, one tooth produced an unprecedented amount of S. mutansDNA, a sign of an extreme imbalance in the oral microbial community.

We were very surprised to see such a large abundance of S. mutans in this 4,000-year-old tooth. It is a remarkably rare find and suggests this man was at a high risk of developing cavities right before his death.

Dr Lara Cassidy, senior author.
Smurfit Institute of Genetics
Trinity College Dublin, Dublin, Ireland.
The researchers also found that other streptococcal species were virtually absent from the tooth. This indicates the natural balance of the oral biofilm had been upset – mutans had outcompeted the other streptococci leading to the pre-disease state.

The team also found evidence to support the "disappearing microbiome" hypothesis, which proposes modern microbiomes are less diverse than those of our ancestors. This is cause for concern, as biodiversity loss can impact human health. The two Bronze Age teeth produced highly divergent strains of Tannerella forsythia, a bacteria implicated in gum disease.

These strains from a single ancient mouth were more genetically different from one another than any pair of modern strains in our dataset, despite the modern samples deriving from Europe, Japan and the USA. This represents a major loss in diversity and one that we need to understand better.

Iseult Jackson, first author.
Smurfit Institute of Genetics
Trinity College Dublin, Dublin, Ireland.
Very few full genomes from oral bacteria have been recovered prior to the Medieval era. By characterising prehistoric diversity, the authors were able to reveal dramatic changes in the oral microenvironment that have happened since.

Over the last 750 years, a single lineage of T. forsythia has become dominant worldwide. This is the tell-tale sign of natural selection, where one strain rises rapidly in frequency due to some genetic advantage it holds over the others. T. forsythia strains from the industrial era onwards contain many new genes that help the bacteria colonise the mouth and cause disease.

S. mutans has also undergone recent lineage expansions and changes in gene content related to pathogenicity. These coincide with humanity’s mass consumption of sugar, although we did find that modern S. mutans populations have remained more diverse, with deep splits in the S. mutans evolutionary tree pre-dating the Killuragh genome.

Dr Lara Cassidy.
The scientists believe this is driven by differences in the evolutionary mechanisms that shape genome diversity in these species.

S. mutans is very adept at swapping genetic material between strains. This means an advantageous innovation can be spread across S. mutans lineages like a new piece of tech. This ability to easily share innovations may explain why this species retains many diverse lineages without one becoming dominant and replacing all the others.

Dr Lara Cassidy.
In effect, both these disease-causing bacteria have changed dramatically from the Bronze Age to today, but it appears that very recent cultural transitions in the industrial era have had an inordinate impact.
Technical details and background to the research is given in the team's open access paper in Molecular Biology and Evolution:

Abstract

Ancient microbial genomes can illuminate pathobiont evolution across millenia, with teeth providing a rich substrate. However, the characterization of prehistoric oral pathobiont diversity is limited. In Europe, only preagricultural genomes have been subject to phylogenetic analysis, with none compared to more recent archaeological periods. Here, we report well-preserved microbiomes from two 4,000-year-old teeth from an Irish limestone cave. These contained bacteria implicated in periodontitis, as well as Streptococcus mutans, the major cause of caries and rare in the ancient genomic record. Despite deriving from the same individual, these teeth produced divergent Tannerella forsythia genomes, indicating higher levels of strain diversity in prehistoric populations. We find evidence of microbiome dysbiosis, with a disproportionate quantity of S. mutans sequences relative to other oral streptococci. This high abundance allowed for metagenomic assembly, resulting in its first reported ancient genome. Phylogenetic analysis indicates major postmedieval population expansions for both species, highlighting the inordinate impact of recent dietary changes. In T. forsythia, this expansion is associated with the replacement of older lineages, possibly reflecting a genome-wide selective sweep. Accordingly, we see dramatic changes in T. forsythia's virulence repertoire across this period. S. mutans shows a contrasting pattern, with deeply divergent lineages persisting in modern populations. This may be due to its highly recombining nature, allowing for maintenance of diversity through selective episodes. Nonetheless, an explosion in recent coalescences and significantly shorter branch lengths separating bacteriocin-carrying strains indicate major changes in S. mutans demography and function coinciding with sugar popularization during the industrial period.

Introduction

The oral cavity is the most well-studied aspect of the ancient human microbiome, mainly due to the excellent preservation of DNA in calculus (fossilized dental plaque). However, three quarters of published ancient oral metagenomes date to within the last 2,500 years, with few full genomes available from prior to the medieval period (Fellows Yates et al. 2022). While a small number of much older preagricultural genomes have yielded important insights (Fellows Yates et al. 2021), prehistoric diversity and the impact of Holocene dietary transitions are not well characterized. Common oral taxa identified in these metagenomes include the “red complex” bacteria Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis, which are important in the development of periodontitis, a highly polymicrobial disease (Socransky et al. 1998). However, another species with a major impact on public health, Streptococcus mutans, is not preserved in calculus (Velsko et al. 2019), and has no published ancient genomes.

Streptococcus mutans is the primary cause of dental caries (Lemos et al. 2019.1), and is common in modern oral microbiomes (Achtman and Zhou 2020). Its lack of preservation in ancient microbiomes may be largely due to its acidogenic nature; acid degrades DNA and prevents plaque mineralization, which is the main substrate used for sampling (Velsko et al. 2019). Its absence may also reflect less favorable habitats for S. mutans across most of human history. Indeed, metagenomic surveys of ancient and modern microbiomes suggest that the species only became a dominant member of the oral microbiota after the medieval period due to major dietary changes, such as the popularization of sugar (Adler et al. 2013; Achtman and Zhou 2020). However, another study of modern genomes has placed more emphasis on the Neolithic transition as a driver of S. mutans proliferation (Cornejo et al. 2013.1). Caries are observed more frequently in the archaeological record after the adoption of cereal agriculture, but rise in incidence through time with a sharp increase in the Early Modern period (Bertilsson et al. 2022.1).

The relative importance of prehistoric and recent dietary transitions in the evolution of red complex bacteria is also poorly characterized. Tannerella forsythia is one of the better studied species (Warinner et al. 2014; Bravo-Lopez et al. 2020.1; Philips et al. 2020.2; Honap et al. 2023), with 55 genomes currently available (supplementary table S1, Supplementary Material online). Surveys of preagricultural (Fellows Yates et al. 2021) and European medieval diversity (Warinner et al. 2014; Philips et al. 2020.2) have shown no clear temporal trends in T. forsythia phylogenetic structure, although functional differences between ancient and modern genomes have been observed (Warinner et al. 2014; Philips et al. 2020.2). However, these data have not been coanalyzed. Here, we shed light on prehistoric oral pathobiont diversity, as well as recent changes in these species’ demography and functional repertoire, by retrieving the first ancient S. mutans genome and two distinct strains of T. forsythia from a single Early Bronze Age individual.

[…]

Conclusion

Adding a temporal dimension to pathogen genomics allows us to better estimate the timing of key evolutionary changes, as well as to capture extinct diversity. In this study, we have reconstructed ancient genomes for T. forsythia and S. mutans, which demonstrate dramatic changes in oral pathobiont population dynamics and functional composition in the last 750 years. For both species, there is a distinction between postindustrial and earlier genomes in terms of virulence factors. This is clearest in T. forsythia, where there is a temporal transect of ancient genomes: here, preindustrial genomes have a stark difference in functional repertoire compared to industrial and modern genomes. Both the host immune response and interactions with other oral microbes would be impacted by these changes. Although there is only 1 ancient S. mutans genome (KGH2-B) of sufficient quality to compare with the modern dataset, analysis in tandem with phylogenetic information implies that the modern mutacin repertoire is also a relatively recent acquisition.

Concurrent population expansions were inferred in both S. mutans and T. forsythia phylogenies in the postmedieval period, but extant S. mutans populations harbor much deeper diversity compared to T. forsythia. We hypothesize that this is related to the species’ different susceptibilities to genome-wide selective sweeps, which are more likely to occur when within-population recombination is low (Bendall et al. 2016). Streptococcus mutans is a highly recombining species (Cornejo et al. 2013.1), allowing advantageous variation to be exchanged between population members and resulting in gene-specific sweeps. In T. forsythia, genome structure is relatively stable and small-scale mutation appears to be the major driving force of diversification (Endo et al. 2015). This could lead to repeated purges in genetic heterogeneity in the population. These purges may have intensified in the past several centuries, as evidenced by the loss of diversity in modern and industrial populations, relative to prehistoric strains from the same Early Bronze Age individual. In general terms, higher biodiversity in ecosystems makes them more resilient to perturbations from environmental stressors (e.g. dietary changes and colonization by pathogenic bacteria in the case of the oral microbiome). The reduction in T. forsythia diversity over time coincides with a general loss of oral biodiversity discussed in Adler et al. (2013).

Going forward, denser sampling of ancient microbial populations may provide new insights into the evolutionary mechanisms that underlie bacterial taxon formation, adaptation and maintenance of diversity, which can vary depending on species and environment. Some species will be more amenable to dense temporal sampling than others. In particular, low levels of S. mutans preservation in the ancient DNA record may pose a significant challenge. Targeted capture of genes of interest (e.g. mutacins) as well as the core genome may provide a solution, but risks losing pangenomic diversity. In the case of T. forsythia, which is more abundant in the archaeological record, ancient metagenomic assemblies in the future may allow for the identification of hitherto unknown virulence factors in earlier strains; our analysis here is limited to the genomic content of modern T. forsythia samples, as all the ancient genomes are reference-aligned.

Overall, our findings demonstrate the utility of ancient genomes in characterizing different modes of pathobiont evolution. Temporal resolution of virulence genes can provide further insight into the shifting selection regimes of pathobionts in the human oral microbiome. In addition, these results highlight that recent cultural transitions, such as the popularization of sugar, are most relevant to understanding the shaping of present-day oral pathobiont diversity.

There is a lot there for creationists to try to ignore or lie about, either to themselves or to the fools they are trying to recruit into their money-making scam.

  1. There is the geological evidence of a limestone cave which takes millions of years to form.
  2. There is the evidence for evolution in the differences between the genomes of the micro-organisms found on the plaque on the surface of the teeth.
  3. There is the absence of any evidence for a global flood in the fact that the contents of the cave have not been submerged in water and have none of the inevitable deposits on them that would have resulted from such a flood.
  4. There is the evidence that there were people living in Ireland 4,000 years ago when creationists legend says they should all have been drowned in a global flood (which apparently never reached County Limerick).
  5. There is the evidence for evolution in both the micro-organisms themselves and also in the biodiversity of the human oral microbiome which have changed significantly as the main sources of food have changed, showing how the environment drives evolutionary change.
All in all, a great deal of cognitive dissonance for which creationists will need to employ their usual coping mechanisms.
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Saturday 23 March 2024

Creationism in Crisis - Now It's a Giant Amazon Dolphin from 16 Million Years Before 'Creation Week'!


Type specimen (holotype) of Pebanista yacuruna, including a photo of the specimen and a surface 3D model in dorsal view.

Image: Aldo Benites-Palomino.
Ancient Giant Dolphin Discovered in the Amazon | | UZH

The third in a clutch of very recent papers casually refuting the childish beliefs of the creation cult.

This one concerns a giant freshwater dolphin that inhabited the Amazon 16 million years before creationists think there was a Universe, let alone an Earth with life on it.

Tell me about the Peruvian Amazon 16 million years ago. Around 16 million years ago, during the Middle Miocene epoch, the Peruvian Amazon region would have been significantly different from its present-day appearance. This period falls within the broader geological timeframe known as the Neogene Period, characterized by significant changes in climate and biodiversity.

During this time, the Amazon basin was undergoing a transformation from a relatively dry environment to a more humid and tropical one. The climate was warmer and wetter compared to today, with vast stretches of lush tropical rainforest covering much of the region.

The landscape would have been dominated by dense forests, rich in diverse flora and fauna. Ancient ancestors of many of today's Amazonian species would have been present, including various types of plants, mammals, birds, reptiles, and insects. Megafauna such as giant ground sloths, glyptodonts, and various types of large herbivores and predators may have roamed the area.

The river systems of the Amazon basin would have been different as well, as the Andes Mountains continued to uplift and shape the landscape. However, the basic hydrological structure of the Amazon River and its tributaries would have already been established, providing the necessary water sources for the flourishing ecosystems.

Overall, the Peruvian Amazon 16 million years ago would have been a vibrant and biodiverse ecosystem, albeit with species compositions and environmental conditions differing from those of today due to ongoing geological and climatic changes over millions of years.

Friday 22 March 2024

Creationism in Crisis - How Batesian Mimicry In The Female Diadem Butterfly Evolved - Convergently


The female Diadem (bottom left) mimics the African Queen (top left). The male Diadem (right) keeps a distinct pattern to attract mates
Scientists discover how Diadem butterfly mimics African Queen - News

This is the second in a sudden spate of research papers that casually and unintentionally refute creationism without even trying, simply by revealing the facts. It deals with the evolution of Batesian mimicry in a species of butterfly.

Scientists working at the universities of Exeter, Edinburgh and Cambridge, and Mpala Research Centre in Kenya have discovered the genetic basis for the clear example of Batesian mimicry to be found in the female of the pantropical species of butterfly, the Diadem butterfly, Hypolimnas misippus, which closely resembles the toxic African queen butterfly, Danaus chrysippus.

Batesian mimicry is the natural phenomenon where an otherwise harmless species evolves to resemble a harmful or distasteful species as a defence mechanism. The prerequisite for Batesian mimicry to evolve is that a prey species is predated upon by the predator of a harmful species which coexists in the same locality. The predator learns to avoid the dangerous or distasteful species so any other species that comes to resemble the harmful or distasteful species might be mistaken for it and avoided. The more closely it comes to resemble the avoided species, the more likely it is to survive and reproduce.

Thursday 21 March 2024

Creationism in Crisis - How Hair Evolved From A Keratin Gene In A Frog-Human Common Ancestor


Genetic basis for the evolution of hair discovered in the clawed frog
Western Clawed Frog, Xenopus tropicalis
Carries the precursor gene for mammalian hair.


"When sorrows come, they come not single spies but in battalions" - Claudius in Hamlet.

That was never more true of creationism than it is today with the publication of not just the usual casual refutation of creationism we've come to expect most days, but of four disparate papers each of which casually and unintentionally refutes creationism to anyone who understands biology and is familiar with the basic dogmas of the creation cult, simply by revealing real-world facts.

The papers range from this one, which shows how mammalian hair has its genetic origins in a common human-amphibian ancestor, through how a female butterfly evolved Batesian mimicry, through the discovery of a giant Amazonian dolphin from 16 million years before creationists think Earth existed, to how early modern humans survived a super-volcano eruption in South-West Ethiopia a mere 64,000 years before 'Creation Week'.

With so many papers I'll do my best to cover all of them in the next few days, so keep checking back!

Firstly, the evolutionary origin of mammalian hair.

The gene for this originated in a common ancestor of humans (and the other mammals) and a modern clawed frog. The gene controls the growth of keratin, of which the claws of a clawed frog are composed, as is mammalian hair. The evidence for this common origin was found by researchers from the Medical University of Vienna, Austria, led by led by Leopold Eckhart. The team have published their findings open access in Nature Communications and described their work in a Medical University of Vienna new release:

Creationism in Crisis - Order From Chaos in The Namibian Desert


A typical fairy circle on the Kamberg on the edge of the Namibian Desert

Photo: Stephan Getzin.
Information for the Media - Georg-August-Universität Göttingen

Scientists are hotly debating how the 'fairy circles' which arise in the vegetation on the edge of the Namib desert actually form. Whatever the process, they are examples of order emerging from chaos by the operation of natural forces. The debate is over what exactly those forces are.

Typical of the mindless parroting that constitutes creationism in the social media, is the claim that 'you can't get order from chaos', which of course is nonsense, since any chaotic system will tend to order if a directional force is applied to it.

Suns and galaxies condense out of the chaos of dust and gas clouds under the directional force of gravity; raindrops form in clouds under the directional forces of gravity and electrostatic attraction; and 'fairy rings' form in grassland under the influence of fungal hyphae and nutrient depletion, and rings form in ell grass because of a build-up of toxic sulphides in the marine sediment, just to cite a few examples

Here's a little bit of fun which you can use to show any creationist acquaintance what nonsense they've been fed. Next time you're playing Scrabble, place all the tiles in the upturned box lid and make sure no tile is on top of another. Ask them to swirl it round to show you're not cheating. Observe that the tiles are in a chaotic arrangement. Now apply a directional force in the form of gravity by tipping the box lid about 15 degrees to produce a slope and tapping it or shaking the lid gently to provide a little energy to the system. Observe now that the tiles have formed themselves into neat rows and columns at one end of the lid. If not, give it a little more shaking or tapping.

Order has emerged out of chaos under nothing more magical than the directional force of gravity.

More examples of emergence of order out of chaos are:

Wednesday 20 March 2024

Creationism in Crisis - Closing The Last God-Shaped Gap - How The Simplest Cells Could Have Evolved, Naturally


Last Chance Lake in September 2022. At the end of the summer, the water has almost all evaporated, leaving a salty crust on the surface.

Credit: Zachary R. Cohen/Washington University
Did the first cells evolve in soda lakes?

According to a new study by Zachary R Cohen of the Chemistry Department of Washington University, Seatle, WA, USA and colleagues, soda lakes which are rich in sodium and carbonates could have provided the right conditions for the simplest, RNA-based cells to have arisen.

It is widely assumed that the earliest simple cells were based on RNA enclosed in a lipid membrane but there is a problem in that RNA requires divalent ions such as Magnesium (Mg2+ to function, but Mg2+ damages lipid membranes, so it isn't easy to explain how they could have co-existed within the same cell structure.

So the question is whether the low levels of (Mg2+ found in soda lakes, such as the Last Chance Lake in British Columbia, Canada, could have provided the right conditions of enough (Mg2+ for RNA to function but not so much as to prevent the formation of an enclosing membrane.

To explore this possibility, Zachary Cohen and his colleagues collected water from Last Chance Lake and the similar but subtly different Goodenough Lake after seasonal evaporation. According to information from Washington University published in phys.org:
These soda lakes each contained ~1 M Na+ and ~1 mM Mg2+ at pH 10. The authors found that spontaneous extension of short RNA primers occurred in lake water at a rate comparable to the rates in standard laboratory conditions.

The authors added fatty acids, which could have been available on the early Earth, to the lake water to see if the molecules would assemble into membranes. The membranes formed in dilute water that simulates a rainfall event, and the membranes persisted even when surrounded by concentrated lake water from the dry season.

According to the authors, soda lakes on the early Earth could have supported key features of protocell development, with RNA copying and ribozyme activity taking place in the dry season and vesicle formation occurring during the wet season.
The scientists give more technical details in their open access paper in PNAS Nexus:

Tuesday 19 March 2024

Creationism's Heath-Robinson Designer - Muddling Through With Even More Ramshackle Complexity


Gut Bacteria Make Neurotransmitters to Shape the Newborn Immune System | Newsroom | Weill Cornell Medicine

The story so far, according to the Creationists Gospel:

Once upon a time, just a few thousand years ago, a magic man in the sky magicked a small flat planet with a dome over it in the Middle East, and then made some people to live on it.

It also made lots of harmful bacteria and other parasites to live in them and make them sick, but luckily, it also gave the humans an immune system to stop the parasites it made to make them sick, from doing what it designed them to do.

The only problem was that the ramshackle immune system it designed, which often doesn't do what it was designed to do, is also a little hypersensitive and prone to treating other things like the body it should be protecting as a parasite and mounting an attack on it so we suffer from all sorts of 'autoimmune' diseases that require another layer of complexity to keep in check. The other thing about it is that it needs training and until that's complete, it will treat all manner of things as parasites, including the food babies eat - and that could result in food allergies that would make life miserable!

But rather than do the simple thing and design the immune system to be able to tell the difference between food and harmful parasites, creationism's version of William Heath-Robinson went for one of the most bizarre solutions you can imagine. Rather like William Heath-Robinson's solution to an every-day problem, it co-opted things in the baby's environment to perform functions they were never intended to perform, like an upright piano being used to stand a step-ladder on to give it enough height, or a stick and some string being used to mend a broken spoke in a wheel, creationism's designer co-opted some of the bacteria that live in a baby's gut.

How it did this is explained in a free access paper in Science Immunology by a team of researchers from the Department of Pediatrics at Weill Cornell Medicine, led by Assistant Professor Dr. Melody Zeng of the Gale and Ira Drukier Institute for Children's Research. Their work is described in a Weill Cornel Medicine news item:

Creationism in Crisis - An Ancestral Croccodile from 215 Million Years Before 'Creation Week'


An artist’s interpretation of the newly identified aetosaur Garzapelta muelleri
Márcio L. Castro.
Tanks of the Triassic: New Crocodile Ancestor Identified | Jackson School of Geosciences | The University of Texas at Austin

In that very long period of Earth's history, long before creationism's god decided to create a small flat planet with a dome over it, and before even the dinosaurs rose to pre-eminence, another group of reptiles had evolved into armour-plated tank-like creatures with thick body-plates and fringes of curved spikes to deter predators. Some of these were later to evolve into the modern crocodiles.

Now three researchers from the University of Texas at Austin have identified a new species that lived 215 million years ago in the Triassic. The newly-identified species was found on a museum shelf where it had been since its discovery in Garza County in northwest Texas, some 30 years ago by the palaeontologist, Bill Mueller. The researchers have named the new species in his honor, as Garzapelta muelleri (Pelta = plate).

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:

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:
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