Refuting Creationism - Evolution Of Immunity, Longevity And Cancer Resistance In Bats - No Magic Needed

Myotis bats

Little Brown Bat, Myotis lucifugus. Can live up to 35 years, immune to most viruses and rarely develops cancers

Photo © Michael Durham,
Illinois Department of Natural Resources

Clues to longevity may reside in the genomes of long-lived bats - Berkeley News

Creationists routinely claim that mutation cannot produce new genetic information and that complex biological systems must have been separately designed for their allotted purposes. Yet living genomes bear little resemblance to collections of independently engineered components. Genes are duplicated, deleted, rearranged and modified; the resulting variants are tested by natural selection; and the same molecular machinery is repeatedly recruited for several different functions. A new study of bats provides a particularly revealing example of this evolutionary improvisation.

Viruses and their hosts have been engaged in evolutionary arms races for hundreds of millions of years. Viruses evolve ways to enter cells, evade immune responses and appropriate cellular machinery for their own replication, while their hosts evolve countermeasures. From a creationist perspective, this requires an intelligent designer simultaneously to design the viruses, their means of attacking their hosts and the defensive systems needed to resist them. Evolution provides the far simpler explanation: each side imposes selection on the other, with no foresight, overall plan or concern for the suffering caused along the way.

In a paper published in Nature, an international team of researchers assembled near-complete genomes for eight closely related species of Myotis bat and established primary cell lines with which to test some of the genomic findings. The comparison revealed abundant structural variation—including inversions, translocations and gene duplications—within an otherwise strongly conserved arrangement of chromosomes.

The researchers found that bats have responded differently to different classes of virus. Proteins interacting with DNA viruses showed an unusually strong signature of positive selection, whereas genes interacting with RNA viruses were especially prone to gains and losses of copies. One antiviral gene, EIF2AK2, better known as PKR, occurs in one, two or, in one lineage, three copies. The original duplication appears to have arisen near the base of the Myotis radiation, with duplicated and unduplicated forms persisting across species for tens of millions of years. This is new genetic material arising through mutation and subsequently being retained, modified or lost according to its effects—not information supplied fully formed by an external intelligence.

Refuting Creationism - How We Know The Bible Was Written By Ignorant People - Sex Determination In Geckos

Various Geckos

Source: Wikipedia

XY or ZW? Geckos Reveal Evolution's Hidden Playbook

The simplest way to test the claim that the Bible is the inerrant work of an omniscient creator is to compare its account with observable reality. When that is done, its creation stories reflect the limited biological knowledge of their human authors, not omniscience. Genesis 1:27 presents “male and female” as divinely ordained categories for humans, while the wider biblical narrative assumes the familiar arrangement of sexually reproducing males and females among animals; indeed in Genesis 6:19 the Bible unambiguously states all the animals on the Ark were male and female.

Real biology is much less tidy. Many animal species are simultaneous or sequential hermaphrodites; some lineages consist entirely of females and reproduce by parthenogenesis; and many organisms reproduce without sex at all. The biblical authors displayed only the knowledge expected of people living in an ancient pastoral society. An omniscient creator would have known better.

Nor are the mechanisms that determine sex fixed systems established in a single act of creation, with organisms thereafter reproducing only “after their kind”. They are themselves products of evolution. The new gecko study indicates that different lineages have switched repeatedly between genetic sex determination and environmental sex determination, in which conditions such as egg-incubation temperature influence the offspring’s sex. Even genetic sex determination has repeatedly been reinvented, with different ordinary chromosomes recruited independently to become X and Y or Z and W chromosomes. Instead of one immutable system imposed by a designer, geckos exhibit an evolutionary patchwork assembled and repeatedly modified over millions of years.

The familiar mammalian arrangement in which females are XX and males XY is sometimes treated as though it were the inevitable—and therefore designed—way of determining sex. But nature displays no such uniformity. Birds generally use a ZW system, in which females are ZW and males ZZ, while many reptiles dispense with specialised sex chromosomes altogether and allow environmental conditions, particularly incubation temperature, to influence whether an embryo develops as male or female.

Geckos exhibit all three arrangements, sometimes among relatively closely related species. This extraordinary diversity makes them a natural experiment in how sex-determination mechanisms originate, change and disappear during evolution.

In a new study published in *Science*, Yang Zhou and colleagues compared chromosome-level genomes from geckos representing all seven living families. Their reconstruction indicates that gecko lineages have switched between environmental and genetic sex determination at least 23 times. The researchers identified 22 distinct sex-chromosome systems and traced them to 17 different chromosomes in the ancestral gecko genome. Some of those ancestral chromosomes were recruited independently on several separate occasions.

Refuting Creationism - Now It's A Transitional Early Insect - From 324 Million Years Before 'Creation Week'

Palaeoecological reconstruction of the Carboniferous stem-insect Chosha praecursor

From: Tihelka, E., Vásquez, C., Engel, M.S. et al (32026)

Amphibious stem-insect rewrites the evolutionary history of insect terrestrialization---- Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

A favourite creationist debating tactic is to point to a gap in the fossil record and pretend that the absence of a known transitional form is evidence that no transition occurred. When a suitable fossil is eventually found, the manoeuvre simply creates two smaller gaps on either side of it—or the fossil is arbitrarily declared to be “fully formed” and therefore not transitional. A simple trick which exposes the ignorance and disingenuity of creationism, is to ask them to describe exactly what they would expect a transition fossil to look like. They tend to abruptly break off the debate, because to answer it would violate two unwritten rules of creationism - never consider being wrong and never state what evidence would cause you to change your mind in case it's produced.

This 'god of the gaps' rhetorical game depends upon treating an inevitably incomplete geological record as though it ought to contain a specimen from every generation of every evolving lineage - something that if it were true, would be hard for science to explain, given what we know of the circumstances in which fossils are formed, which actually predicts that the record will be discontinuous.

The early history of insects has offered particularly fertile ground for this tactic. Molecular-clock studies indicate that hexapods diverged from aquatic crustacean relatives hundreds of millions of years ago, yet their small, delicate bodies were poorly suited to fossilisation, especially in the environments through which they were making the transition onto land. Consequently, there has been a conspicuous interval—the so-called “hexapod gap”—between the earliest evidence of hexapods and the abundance of unmistakable insects in later Carboniferous rocks.

Now, an international team led by Erik Tihelka and Chenyang Cai has described a remarkable fossil that helps to narrow that gap while illustrating how the familiar insect body plan was assembled. The approximately 324-million-year-old animal, named Chosha praecursor, came from the Late Mississippian Tesnus Formation of western Texas. Collected in 1985 and long misidentified as a juvenile crustacean, it remained in a museum collection until examination under cross-polarised light revealed anatomical details that had previously been almost invisible. The findings are reported in Nature.

Refuting Creationism - A Road-Map Of Evolution Over 600 Million Years - From A Common Ancestor

The ever-branching tree of animal Evolution

AI-generated image (ChatGPT 5.6 SOL)

Roadmap of animal biodiversity: largest-ever comparison of chromosome-scale genomes

Words such as rules, pathways and highways can become treacherous when scientific findings pass through the hands of religious apologists. A rule, in ordinary speech, suggests someone who made it; a highway suggests an engineer who decided where it should lead. It is therefore easy to anticipate claims that a major new study of animal chromosomes has discovered evidence that evolution follows rules—and that rules must imply a rule-maker directing evolution towards a predetermined goal.

That, however, is not what the researchers have found.

In the largest comparison of chromosome-scale animal genomes yet undertaken, Darrin Schultz and colleagues analysed 5,821 genomes representing 4,454 species in 19 animal phyla. Their study, published in Science Advances, developed what they call “evolutionary genome topology”: a way of mapping the enormous variety of animal genomes according to the organisation and shared ancestry of their chromosomes. The results reveal recognisable, partly irreversible patterns extending back more than 600 million years to the common ancestor of living animals.

The accompanying University of Vienna press release describes these patterns as “evolutionary highways” and says that genomes evolve according to a limited set of “rules”. Those are useful metaphors, but they describe constraints and consequences—not commands, intentions or a plan.

Animal chromosomes can split, fuse and exchange material, but these processes are not free to produce every imaginable arrangement with equal probability. Existing chromosome structure limits what can happen next, while every change becomes part of the starting conditions inherited by subsequent generations. In particular, when ancestral chromosomes fuse and their genes subsequently become intermingled, the original arrangement cannot simply be reconstructed by reversing the fusion. The researchers call this process “fusion-with-mixing”. It makes chromosome evolution path-dependent: where a lineage can readily go next depends partly upon where it has already been.

This is what “rules” means in this context. It no more implies a supernatural rule-maker than the regular formation of crystals implies a crystal designer, or the course taken by a river implies that someone planned its route. Physical and chemical processes have consistent properties; biological structures impose constraints; and inherited history restricts the range of subsequent possibilities. Regular outcomes can emerge from those natural conditions without foresight or intention.

Nor does the statement that genomes “do not change at random” mean that their future has been prescribed. Mutations and chromosome rearrangements can occur without regard to what an organism needs, but randomness does not mean that every conceivable event is equally likely—or even physically possible. Some rearrangements are more readily produced than others; some are lethal or reduce fertility; some survive genetic drift or natural selection; and every surviving arrangement alters the possibilities available to its descendants. Chance operates within constraints, producing statistical patterns rather than fulfilling a programme.

How Science Works - And Why Religion Doesn't - Testing Relativity In Extreme Conditions

The image shows all known stars in the Galactic Center orbiting the central massive black hole Sgr A*. The central region is dominated by young, hot stars (blue), and a couple of cooler stars (orange/red). One of the cooler stars, S301, is approaching Sgr A* very closely, about the distance Sun to planet Saturn. Sgr A* itself is surrounded by hot plasma, the light of which is warped due to the black hole’s strong gravity.

© MPE

This article is best read on a laptop, desktop, or tablet

A spinning black hole drags space-time around it, a phenomenon known as Lense-Thirring effect.

A star with an Extreme Orbit | Max Planck Institute for extraterrestrial Physics

One of the most striking differences between science and religion is that science does not merely offer explanations for what has already been observed. A scientific theory must also make precise predictions about phenomena that may not yet have been detected—and those predictions must expose the theory to the possibility of being proved wrong.

Einstein’s general theory of relativity is an outstanding example. More than a century after it was formulated, astronomers are still finding new ways to test its predictions under conditions far more extreme than anything available to Einstein. The latest opportunity is provided by a faint star named S301, racing around Sagittarius A*, the supermassive black hole at the centre of the Milky Way.

According to a new paper by the GRAVITY+ Collaboration, published in Nature, S301 follows an extraordinarily elongated orbit around the black hole, completing one revolution every 8.7 years—the shortest orbital period yet measured for any star around Sagittarius A*. At its closest approach, it passes only about 1.78 billion kilometres from the black hole, roughly twelve times the distance between Earth and the Sun. There it reaches approximately 25,000 kilometres per second, or more than eight per cent of the speed of light, making it the fastest-known star in the Milky Way.

S301 is not travelling through ordinary space governed adequately by Newtonian gravity. It is plunging deep into the gravitational field of an object containing about 4.3 million times the mass of the Sun. Its orbit therefore acts as a natural probe carried into a region of severely curved spacetime that no human-made spacecraft could approach and survive.

General relativity predicts that an orbit in such a field will not form a perfectly closed ellipse. The point of closest approach shifts with each revolution, producing what is known as Schwarzschild precession—an effect already detected in the orbit of the better-known star S2. S301 approaches Sagittarius A* about ten times more closely than S2 in terms of the black hole’s Schwarzschild radius, so the relativistic effects on its motion should be considerably stronger.

Refuting Creationism - The Slow Evolution and Extinction Of African Megafauna - Over 23 Million Years

Modern African megafauna

A selection of extinct African megaherbivores

AI-Generated image (ChatGPT 5.6 Sol)

Scarce emergence of new species drove the decline of African megaherbivores | Museo Nacional de Ciencias Naturales

Africa’s elephants, rhinoceroses and hippopotamuses are surviving representatives of a much richer assemblage of giant herbivores that once included such animals as Deinotherium, an elephant relative with downward-curving tusks, and the pig-like anthracotheres, relatives of modern hippopotamuses. These animals were not merely conspicuous members of their ecosystems. As “ecosystem engineers”, megaherbivores—here defined as herbivorous mammals weighing at least one tonne—alter vegetation, disperse seeds, open pathways, create water holes and redistribute nutrients.

Why so much of this diversity disappeared has usually been approached as a question of extinction. Large animals reproduce slowly, require extensive habitats and comparatively large quantities of food, so it seems intuitively reasonable to assume that they must have been especially vulnerable when climates and environments changed. Human hunting has also figured prominently in explanations of the much more recent global disappearance of large mammals.

But the diversity of any group depends upon two processes, not one. Extinction removes species, while speciation produces new ones. Even a lineage with a comparatively modest extinction rate will decline if its species disappear faster than evolutionary divergence can replace them. Conversely, a group can withstand relatively frequent extinctions if new species continue to arise sufficiently rapidly.

A new study published open access in Nature Communications. has now examined both sides of that evolutionary balance. Juan L. Cantalapiedra and colleagues analysed 3,327 African fossil occurrences representing 396 species of herbivorous mammals. Using neural-network models, they reconstructed changes in speciation and extinction over the past 23 million years while considering body size, tooth-crown height, evolutionary relationships and environmental change. Their results challenge the apparently obvious assumption that Africa’s largest herbivores declined because they were inherently more prone to extinction.

In fact, the models indicate that extinction rates were generally somewhat lower among the largest species. High-crowned teeth, which better withstand abrasive diets, were also associated with a reduced risk of extinction. The underlying problem for megaherbivores was that their already low speciation rates could not compensate for the species that were lost.

The imbalance developed over millions of years. As Africa became increasingly arid from about 7.2 million years ago, both speciation and extinction initially accelerated as changing vegetation and expanding open habitats reorganised its ungulate communities. Speciation then levelled off after about 3.6 million years, while extinction continued to rise and increased sharply with the beginning of the Pleistocene, about 2.58 million years ago. During the driest intervals, smaller herbivores generated new species at substantially higher rates, whereas speciation among megaherbivores was suppressed still further. The resulting decline was already well under way long before humans possessed the technology needed to hunt such enormous animals systematically.

This does not mean that humans played no part in the most recent losses, nor that climate alone explains every extinction. Rather, it places recent events within a much longer evolutionary history in which changing climate, declining ecosystem productivity, extinction and unequal rates of speciation gradually transformed the African fauna.

Creationism Refuted - How The Grand Canyon Was Formed - No Magic Flood Involved

Grand Canyon’s oldest and deepest rocks were unearthed by massive cliff across ancient USA.

Lost mega-escarpment across ancient USA may explain Grand Canyon missing billion years

Creationists sometimes point to the Great Unconformity in the Grand Canyon as evidence of Noah’s mythical global flood. But an unconformity is not a layer deposited by a flood. It is a surface representing an interval during which older rocks were exposed, eroded and sometimes deformed before younger sediments were laid on top of them. What is “missing” is not evidence; it is rock that either was never deposited or was subsequently removed, with the surviving rocks preserving evidence of what happened in the intervening time.

Creationists attempts to fit the Grand Canyon into their Biblical flood myth range from the sublime to the ridiculous, none of them in the least plausible and designed to appeal to the parochial ignorance that typifies American creationism. Their conclusion is always sacred and immune to contradiction. Facts are accepted or rejected based on whether they support the conclusion or not. Science, by contrast, starts with a neutral view, collects evidence, then takes a view that accounts for that evidence, as always in science, the facts are neutral and the conclusion provisional, contingent on the discovery of more evidence.

At parts of the Grand Canyon, Cambrian sedimentary rocks rest upon much older Precambrian rocks, leaving more than a billion years of geological history unrepresented by sedimentary strata at that particular location. Far from supporting the idea that the canyon’s rocks were deposited during a single year-long catastrophe, the contact records a succession of events involving sedimentation, burial, tectonic disturbance, uplift, prolonged exposure, erosion and renewed deposition.

A new study published open access in the journal Geology now proposes a mechanism that may explain much of the extraordinary erosion responsible for this gap in the south-western United States. Thomas M. Gernon of the University of Southampton and colleagues have reconstructed a continent-scale escarpment that may have developed along the western margin of Laurentia—the ancient continental core of North America—as the supercontinent Rodinia began breaking apart approximately 800–750 million years ago.

Refuting Creationism - Why Sex Evolved

Recombination by sexual reproduction drives adaptive diversity in yeast

AI-generated image (ChatGPT 5.6 Sol)

The why behind sex — Harvard Gazette

For creationists, who typically know little or nothing about evolution and so have no understanding that it is a process that takes place in a population, not an event that happens to individuals, sexual reproduction is a fertile source of disinformation and misunderstanding with which to attack the Theory of Evolution.

For instance, they frequently argue that the probability of the 'first man' and 'first woman' evolving together is so highly unlikely that their myth of the spontaneous creation out of dirt of a man and the cloning of a woman by magic is a far more rational alternative explanation. The science is attacked because when they try to force fit their childish myth of every species having a single ancestral male and female couple into the science of evolution, it doesn't fit well. The possibility of the myth being wrong must never be contemplated, because that would risk having to change their mind.

However, science works by addressing questions, not by throwing stones at infantile straw-man parodies of alternative ideas and declaring victory by default.

For science, sexual reproduction presents evolutionary biology with a different long-standing puzzle. An asexual organism can pass on its entire genome without finding a mate, competing for one or investing energy in courtship. In species with separate sexes, there is also the familiar “twofold cost of males”: only females produce offspring, whereas every member of an asexual population can potentially reproduce.

All else being equal, an asexual lineage should therefore increase more quickly than a sexual one, and indeed there are a few examples of where this is true - a single female vine weevil can quickly populate a window box or plant pot with devastating consequences for the owner as I have found to my cost; a single marbled crayfish can rapidly spread through a new river system, out-competing any native species.

Yet sexual reproduction is widespread among eukaryotes and has persisted for hundreds of millions of years. This does not imply that evolution requires foresight or that sex was introduced by a designer for some future purpose. It means that, under many circumstances, the descendants of organisms that exchange and recombine genetic material must acquire advantages sufficient to offset the immediate costs.

One important advantage is that sex reshuffles the genome. In an asexual lineage, genes are inherited together as a largely indivisible package. A beneficial mutation can therefore carry neighbouring neutral or mildly harmful mutations with it as it spreads through a population—a process known as genetic hitchhiking. Sexual reproduction and recombination can break up these associations, separating advantageous mutations from some of the damaging evolutionary baggage accompanying them.

Creationism Refuted - The Simple Mutation That Made Grasses So Successful - 100 Million Years Before 'Creation Week'

Joinvillea ascendans, a close relative of grass plants. Used in the Study

Photo: Sarah Friedrich.

Maeda and his collaborators sequenced the slow-growing Joinvillea ascendans plant, a close relative of grasses, to compare genomes and learn what makes grass plants unique.

Photo: Sarah Friedrich.

Molecular “bypasses” improve grass plants’ synthesis of lignin and starch, laying the early groundwork for evolutionary success – Department of Biology – UW–Madison

Creationists routinely claim that mutations can only damage genetic “information” and can never produce anything genuinely new. The claim depends partly upon leaving information conveniently undefined and partly upon ignoring the many well-understood processes by which genomes acquire new functions. Gene duplication, mutation and natural selection can preserve an existing function while a spare copy accumulates changes, sometimes enabling it to perform an additional task or participate in a new biochemical pathway.

A new study published in Science provides an unusually clear example. Rather than merely showing that related organisms possess different enzymes, Yuri Takeda-Kimura and colleagues reconstructed how two important metabolic innovations arose during the ancestry of grasses: additional routes for producing starch and lignin. They did this by comparing the genomes of grasses with those of several of their closest non-grass relatives, including Joinvillea, Ecdeiocolea, Pharus and Typha.

Abiogenesis News - How RNA Droplets Could Have Preceded The First Cells - No Magic Required

RNA condensates forming in an early-Earth mineral pool

AI-generated image (ChatGPT 5.6 Sol)

RNA droplets may have helped start life on Earth. A new study explains why they form - University at Buffalo

One of the enduring questions in origin-of-life research is how the first biologically useful molecules could have become sufficiently concentrated to interact before cells, complete with enclosing membranes, had evolved. Dispersed throughout an ocean or pond, relatively fragile molecules such as RNA would have been unlikely to encounter one another often enough to sustain complex chemical reactions and would have remained exposed to environmental degradation. Some form of compartmentalisation therefore appears to have been an important intermediate stage between unorganised prebiotic chemistry and the first true cells.

Creationists routinely present this and other unanswered questions about abiogenesis as though they were evidence for supernatural intervention. The familiar argument is that, because scientists have not yet reconstructed every step between simple chemistry and the earliest life, an unexplained creator must have supplied whatever is missing. This is merely the false dichotomy and the god-of-the-gaps fallacy masquerading as an explanation. A gap in current scientific knowledge is not evidence that magic occurred inside it, and the history of science is largely a history of such gaps being progressively narrowed by evidence.

Research led by physicist Priya R. Banerjee of the University at Buffalo has now identified a potentially important natural mechanism that could have helped solve the problem of pre-cellular compartmentalisation. In a paper published in Nature Communications, Gable M. Wadsworth and colleagues compared the behaviour of RNA with that of single-stranded DNA carrying essentially equivalent nucleotide sequences. They found that RNA was markedly more inclined to gather spontaneously into microscopic, liquid-like droplets known as biomolecular condensates.

These condensates are not cells and are not enclosed by lipid membranes. Nevertheless, they could perform part of the function later assumed by cellular compartments: bringing molecules together in a confined space, increasing the likelihood of interactions and potentially providing some protection from hostile surroundings. The experiments showed that RNA began forming droplets at temperatures about 10 °C lower than the corresponding DNA and was also more prone to developing interconnected, gel-like molecular networks. Such networks might have retained and protected RNA more effectively than freely dispersed molecules could have done. The researchers used temperature-controlled microscopy, small-angle X-ray scattering and molecular-dynamics simulations to investigate the effect.

Remarkably, much of the difference can be traced to a very small chemical distinction between RNA and DNA. The ribose sugar in RNA carries a hydroxyl group at its 2′ position—the 2′-OH group—which is absent from the deoxyribose sugar of DNA. The experiments and computer simulations indicated that this group alters RNA’s interactions with magnesium ions and the surrounding water, helping RNA strands to associate with one another. When the researchers chemically modified the 2′-OH group, RNA’s tendency to condense weakened and the physical properties of the resulting droplets changed. A single chemical group on each sugar unit can therefore influence the emergence of structures many times larger than the individual molecules themselves.

Refuting Creationism - Japanese Jōmon People Diversified From Other Asian People About 10,000 Years Before 'Creation Week'

[caption]

[credit]

Japanese Archipelago during the last glacial maximum (LGM) when sea-levels were at their lowest. Grey areas were land which is now submerged.

Cold-Climate Adaptations of East Eurasian Hunter-Gatherers Who Lived During the Ice Age, as Revealed by the Jomon Genome - SCHOOL OF SCIENCE THE UNIVERSITY OF TOKYO

Belief in the literal truth and inerrancy of the Bible’s origin myths somehow staggers on, despite their complete lack of supporting evidence and the repeated contradiction of their testable claims by evidence from the real world. It survives through the careful avoidance of inconvenient facts, a steady supply of misinformation and an assortment of strategies for dismissing evidence and suppressing the cognitive dissonance between what believers have been taught and what the evidence shows.

Within this intellectually impoverished and parochial culture, changing one’s mind in response to new information is treated as weakness rather than intellectual honesty, while ignorance of societies beyond the Bible’s narrow geographical horizon makes their histories easier to disregard. One such history is that of the Jōmon people of Japan—a population whose origins, migrations and adaptations extend far back into that immense expanse of human history before creationism’s supposed ‘Creation Week’.

The genomes of ancient people can preserve evidence not only of ancestry and migration but also of the environments in which their distant ancestors evolved. Genetic variants that became unusually common in a population may reveal where natural selection acted, particularly when several independent signals affect biological pathways relevant to the same environmental challenge.

This is the approach taken by an international research team led by Yusuke Watanabe, Yoshiki Wakiyama and Hiroki Oota of the University of Tokyo. In a paper published in Science Advances, the researchers analysed genome-wide data from 42 Jōmon individuals: 25 newly sequenced for the study and 17 whose genomes had previously been reported.

The individuals themselves lived during the Holocene, not during the Last Glacial Maximum. What their DNA preserves, however, is the genetic legacy of a much older population. The researchers estimate that the ancestral Jōmon lineage separated from continental East Eurasian populations sometime between approximately 27,000 and 19,000 years ago—broadly coinciding with the coldest part of the last Ice Age. After becoming established in the Japanese archipelago, this population remained comparatively isolated and later differentiated into regional Jōmon lineages.

The genomic history was not one of absolute separation. The analysis also detected gene flow from northern Upper Palaeolithic Siberians, adding another strand to the already complex history of East Asian populations. Conversely, the researchers found no evidence of Denisovan ancestry unique to the Jōmon lineage, suggesting that any such ancestry had entered the ancestors of East Asian populations before the Jōmon lineage diverged from continental groups.

Unintelligent Design - The Evolutionary Compromises That Made The Human Female Pelvis - No Intelligence Involved

Virtual reconstructions of the Neanderthal pelvises of a 1.5-year-old infant from Dederiyeh Cave, Syria (left), and a young adult female from Sima de las Palomas de Cabezo Gordo, Spain (right). Age- and sex-matched modern human pelvises are superimposed in transparency to highlight form differences.

Image credit: Marcia Ponce de León
and Christoph Zollikofer
(University of Zurich)

A Neanderthal woman and Baby. Her Pelvis is the result of the same evolutionary processes as that of Homo sapiens women.

AI-generated image (ChatGPT 5.6 Sol).

Rethinking Birth and Bipedalism - School of Science University of Tokyo

The human pelvis is a particularly poor candidate for anyone wishing to argue that the human body was intelligently designed from scratch. It must support the upper body, anchor muscles used in standing and locomotion, protect internal organs, maintain the pelvic floor and— in females—provide a passage through which a large-bodied, large-brained infant can be born. The result is not an ideal solution to a single engineering problem, but an evolutionary compromise assembled by modifying an inherited structure while several competing selection pressures acted upon it.

For much of the past century, one influential explanation for its shape has been the “obstetrical dilemma”. According to the simplest version of this hypothesis, the female pelvis represents a compromise between a birth canal wide enough to accommodate a large-brained baby and hips narrow enough to permit efficient bipedal walking. Childbirth pushes pelvic evolution in one direction, in other words, while locomotion pushes it in the other.

That explanation has never been beyond dispute. Studies have questioned whether wider hips necessarily impose the assumed energetic penalty on walking or running, while alternative hypotheses have emphasised maternal metabolism, infant development and the need for a stable pelvic floor capable of supporting the abdominal organs. The pelvis is involved in too many functions for its evolution necessarily to be reduced to a single contest between walking and childbirth.

Refuting Creationism - Observed Evolution Of Live Birth in the European Common Lizard

European common lizard, Zootoca vivipara

Image credit: Meredith Kimble

European common lizard, Zootoca vivipara

By Ocrdu - Own work, CC BY-SA 4.0, Link

University of Glasgow - University news - Scientists uncover the evolutionary process behind live birth in lizards

Live birth is not a simple characteristic that could be produced by switching a single gene on or off. Retaining embryos inside the mother until they are sufficiently developed to survive requires coordinated changes in gestation length, uterine physiology, eggshell formation, gas exchange, nutrient transfer, hormonal control and the maternal immune response. To creationists, this is just the sort of complex biological system that must supposedly have appeared complete and fully functional in a single act of creation.

But that is not what the genomes of living animals show.

In a study recently published in Current Biology, an international team led by Dr Hongxin Xie of the University of Glasgow has reconstructed how live birth evolved in the Eurasian common lizard, Zootoca vivipara. The transition did not depend upon one miraculous genetic leap, or even upon one or two mutations of exceptionally large effect. It arose through natural selection acting upon numerous genetic changes distributed across the genome and accumulated over an extended period.

Refuting Creationism - Denisovans Show Why Scepticism Is The Stuff Of Good Science, But Toxic To Creationism

The Harbin cranium

From: Fu Q, Cao P, Dai Q (2025)

Reconstruction of Homo longi from the Harbin cranium, now identified as that of a Denisovan.

© Nobu Tamura, CC BY-SA 3.0, via Wikimedia Commons.

Were Denisovans tall compared to other ancient humans? We should be sceptical

One of the most important differences between science and creationism is not that science possesses absolute certainty while creationism does not. It is that science has procedures for recognising uncertainty, testing assumptions and preventing an interesting possibility from being promoted prematurely into an established fact. Creationism, by contrast, begins with an asserted certainty and then selects, distorts or dismisses the evidence according to whether it supports the required conclusion.

That distinction is illustrated particularly well by the recent suggestion that Denisovans may have been exceptionally tall. The claim originated in a preprint by Yousuke Kaifu and colleagues describing an incomplete femur and tibia recovered by dredging from the Penghu Channel between Taiwan and mainland China. Ancient proteins preserved in the bones identify them as Denisovan, giving scientists the first known Denisovan leg bones and potentially valuable information about the bodies of these enigmatic archaic humans.

Penghu 2 and Penghu 3 hominin leg bones.
Anterior (a), medial (b), and distal (c) views of the Penghu 2 right femoral shaft. Anterior (d), lateral (e) and distal (f) views of the Penghu 3 right tibia. Symbols: m=medial, p=posterior. Scale bar=10cm.

Kaifu, Y., et al.(2026)

Reconstructions suggest that the owner of the femur, known as Penghu 2, may have stood about 1.8 metres tall and weighed approximately 83 kilograms. The owner of the Penghu 3 tibia may have been about 1.9 metres tall and weighed around 91 kilograms. These were undoubtedly large individuals by Pleistocene standards, and their estimated dimensions compare with those of some of the largest ancient humans known from Africa and Europe.

But two large individuals do not establish that Denisovans as a population were exceptionally tall. Modern humans vary considerably in height, and no responsible anthropologist would attempt to calculate the average stature of the entire species from two people selected from a crowd. The problem is even greater when dealing with two incomplete bones recovered by trawling rather than from a documented archaeological excavation. Their exact discovery locations and original geological contexts are unknown, while large, robust bones are more likely than small or fragile ones to survive, become caught in fishing nets and be recognised as scientifically interesting.

This is the point made by palaeoanthropologist Sally Christine Reynolds in an article in The Conversation. The height estimates may be perfectly reasonable for the two individuals concerned, but extending those estimates to Denisovans generally would require a much larger and more representative sample. At present, “two Denisovans were tall” is a defensible conclusion; “Denisovans were a tall species” remains an intriguing but weakly supported generalisation.

This is evolutionary population thinking in practice. Species are not collections of identical specimens conforming to an ideal form. They are variable populations in which individuals differ because of their genes, sex, nutrition, health, environment and developmental history. Treating one or two specimens as definitive representatives of an entire species is a remnant of the typological thinking that sits much more comfortably with the creationist notion of separately manufactured and essentially unchanging “kinds”.

Creationists habitually misrepresent scientific disagreements about details as evidence that scientists are abandoning evolution. Nothing of the sort is happening here. Reynolds is not questioning whether Denisovans existed, whether they shared common ancestry with Neanderthals and Homo sapiens, or whether they interbred with the ancestors of some living people. She is questioning whether two bones provide sufficient evidence for one proposed characteristic of the Denisovan population.

Indeed, identifying these bones as Denisovan depended upon evolutionary science. Proteins change through inherited mutations, so similarities and differences in their amino-acid sequences retain evidence of common ancestry. Even when recoverable DNA and diagnostic skeletal features are unavailable, palaeoproteomics can place a fossil within an evolutionary family tree. Creationism supplies no corresponding method for predicting those nested molecular relationships and no explanation for why the history recorded by fossil proteins should agree with that reconstructed from DNA and anatomy.

One qualification should be added to the account in The Conversation. Reynolds states that neither bone has been dated directly. However, a companion preprint reporting radiocarbon and stable-isotope analyses gives Penghu 3 a direct radiocarbon age of approximately 45,575–44,522 calibrated years before the present. Penghu 2 remains undated, and the lack of stratigraphic provenance still prevents the two individuals from being assumed to have lived together or even during the same period. Both studies are also preprints and have yet to complete peer review.

Scientific scepticism therefore does not weaken the evolutionary account; it protects it from exaggeration. Scientists can accept that the bones belonged to two large Denisovans, recognise the importance of their molecular identification and direct dating, and nevertheless withhold judgement on whether Denisovans generally were unusually tall. That willingness to make the conclusion no larger than the evidence can support is one of the defining strengths of science—and the antithesis of a creationist doctrine in which the conclusion was declared infallible before any evidence was examined.

Sally Christine Reynolds's article in The Conversation is reprinted here under a Creative Commone License, reformatted for stylistic consistency:

Creationism in Crisis - Penguin Fossils Expose Creationist Lies

Ancient Penguin Fossils Offer New Window into Antarctica’s Changing Climate | Blog

Fossil collection sites, Seymour Island, Antarctica.
Images credit: Boyang Xia et al.

Embarrassed by the wealth of fossils documenting an orderly succession of changing life over hundreds of millions of years, creationists traditionally fall back on several almost equally implausible attempts to reconcile the evidence with their preferred origin myth. According to young-Earth creationism, Earth is only 6,000–10,000 years old, while most of the fossil-bearing geological record was supposedly produced during a single, year-long global flood in which almost every terrestrial vertebrate was exterminated in an act of divine genocide, leaving only a handful of survivors aboard a wooden boat.

The principal pseudo-scientific attempt to explain the orderly fossil record is something creationists call “hydrological sorting”. This proposes that the Flood sorted organisms according to such factors as their size, density, buoyancy, habitat or ability to escape the rising water. The term therefore has a nominal meaning, but it provides no credible explanation for the observed succession of organisms in the rocks. It cannot explain why particular groups appear only after their presumed ancestors, why countless short-lived species occur in a consistent order across different continents, why terrestrial and marine ecosystems succeed one another coherently, or why the same sequence agrees with radiometric dates, palaeomagnetism, plate tectonics and independent records of environmental change.

When this supposed mechanism fails, creationists can retreat into claims that are conveniently immune to evidence: that their creator deliberately planted or manipulated the fossil record to make Earth look ancient; that Satan planted the evidence to deceive the faithful; or that generations of geologists, palaeontologists, physicists and biologists have participated in a vast conspiracy to conceal the “truth”. Each claim abandons any pretence of scientific explanation because none can be tested, falsified or distinguished from an invented excuse. They serve only to protect a predetermined conclusion from inconvenient facts.

The latest inconvenient facts come from three researchers at the China University of Geosciences (Beijing): Boyang Xia, Huaichun Wu and Quanguo Li. In a paper recently published in the open-access journal Fossil Record, they report that fossil penguin bones from Seymour Island, off the Antarctic Peninsula, preserve a geochemical record of changing environmental conditions during the Eocene.

Seymour Island contains one of the world’s richest and most nearly continuous successions of Eocene penguin fossils. Xia and colleagues examined bones from three different levels in the La Meseta and Submeseta formations: an early Eocene horizon dated to 55.3–54.1 million years ago, a younger horizon dated to 49.1–45.8 million years ago, and a middle-to-late Eocene horizon dated to 41.2–37.7 million years ago. For comparison, they also examined bones from living chinstrap and emperor penguins.

Creationism in Crisis - Hunting for Earth’s First Complex Life

The bird cliff Stappen, southern Bjørnøya (Bear Island) in the Barents Sea. The island is part of Svalbard, Norway.

Michael Haferkamp,
CC BY-SA 3.0, via Wikimedia Commons

Microfossils from a sediment core of the Deep Sea Drilling Project (DSDP), Sediment sample with microfossils

Hannes Grobe (talk), Alfred Wegener Institute,
CC BY 3.0, via Wikimedia Commons

On The Hunt For Earth’s First Complex Life - Universe Today

For most of its history, Earth was not a planet of trees, animals, fungi or anything else visible without a microscope. It was a microbial world. Life had existed for well over a billion years before the first clearly recognisable eukaryotic cells appeared in the fossil record, and for roughly another billion years after that, complex life remained comparatively inconspicuous.

That immense, slowly unfolding history is the subject of On the Hunt for Earth’s First Complex Life, an article in Universe Today by science journalist Bruce Dorminey, based on an interview with University of Oxford palaeontologist Associate Professor Ross Anderson. Anderson studies some of the most elusive fossils on Earth: the microscopic and usually soft-bodied remains of the organisms that preceded animals, plants and fungi.

The article is not a report of one new research paper, but an overview of an active field of research. Fortunately, several peer-reviewed studies provide the scientific background to Anderson’s comments. Together they describe not a sudden act of creation, but a long evolutionary transition from a biosphere dominated by bacteria and archaea to one containing eukaryotic cells, multicellular organisms and, eventually, animals.

From a Microbial World to Complex Life. For most of Earth’s approximately 4.54-billion-year history, life was microscopic. The dates below represent the oldest reasonably secure evidence currently known, not necessarily the moment at which each evolutionary innovation first appeared. Any organism must have evolved before it could leave a fossil, and the earliest members of a lineage may have gone unpreserved or remain undiscovered.

Some major milestones

• About 4.54 billion years ago — Earth formed. The young planet initially experienced intense volcanism, impacts and chemical evolution before stable oceans and environments capable of supporting life developed.
• More than 3.5 billion years ago — microbial life was established. Ancient rocks preserve chemical and structural evidence of organisms that lacked nuclei and other membrane-bound organelles. Some proposed evidence is older, but its biological origin remains disputed.
• By about 2.7–2.3 billion years ago — oxygenic photosynthesis had evolved. Cyanobacteria began using sunlight to extract electrons from water, releasing oxygen as a by-product.
• About 2.4 billion years ago — the Great Oxidation Event. Oxygen began accumulating persistently in the atmosphere. This did not immediately produce complex life, but it profoundly altered ocean chemistry, mineral formation and the evolutionary opportunities available to organisms.
• At least 1.75 billion years ago — recognisable eukaryotes. Organic-walled microfossils from northern Australia are among the oldest well-supported fossil eukaryotes. Their distribution indicates that they lived on or within oxygenated seabeds and probably already possessed mitochondria.
• By about 1 billion years ago — multicellular eukaryotes. The fossil record contains increasingly persuasive examples of multicellular algae and other organisms in which cells were joined and organised. Multicellularity subsequently evolved independently in several eukaryotic lineages.
• About 791 million years ago — diverse eukaryotes in the Svalbard sea. The Svanbergfjellet Formation preserves green algae and several enigmatic organisms with complex multicellular forms.
• About 720–635 million years ago — Cryogenian global glaciations. During the “Snowball Earth” episodes, ice extended into tropical latitudes. The resulting environmental disruption probably caused extinctions while also creating new ecological opportunities after the ice retreated.
• By about 574 million years ago — macroscopic Ediacaran organisms. Large, soft-bodied organisms appeared in marine ecosystems. Some may have been early animals, although the precise affinities of several famous Ediacaran forms remain debated.
• From about 539 million years ago — the Cambrian radiation. Animal diversity, movement, burrowing, predation and biomineralisation expanded dramatically over millions of years. Skeletons and shells also made organisms much more likely to enter the fossil record.

How do scientists recognise a fossil eukaryote?

Finding a microscopic structure in an ancient rock does not automatically establish that it was alive, still less that it was a eukaryote. Palaeontologists first determine whether the object is genuinely biological, whether it was deposited with the surrounding sediment and whether it is as old as the rock containing it. They then examine combinations of features that are difficult to explain as mineral growths, later contamination or ordinary bacterial cells.

• Size: Many early eukaryotic fossils are more than 100 micrometres across, considerably larger than typical bacteria. Size alone is not decisive, however, because some bacteria also produce exceptionally large cells.
• Complex walls: Multiple wall layers, regularly arranged spines, sculptured surfaces and other elaborate structures indicate a degree of cellular control associated with eukaryotes.
• Controlled openings: Some fossils have deliberately formed openings through which a cell apparently emerged from a resistant cyst. Their regular shape and position distinguish them from accidental tears or decay.
• Internal structures: Preserved internal bodies, membranes or consistent patterns of cell division can support a eukaryotic interpretation, although claims that a particular structure represents a nucleus or organelle require especially strong evidence.
• Multicellular organisation: Regular arrangements of connected cells, branching, differentiated regions or structures resembling holdfasts can demonstrate controlled growth rather than a chance aggregation of microorganisms.
• Organic chemistry: Microscopy and spectroscopic techniques can establish that a fossil has a carbon-rich biological wall and reveal how heat, pressure and mineral reactions altered it after burial.
• Geological context: Sedimentology and geochemistry reveal whether the organism lived in a coastal lagoon, on an oxygenated seabed or in deeper anoxic water. Finding the same form repeatedly within an appropriate environment strengthens its biological interpretation.

No single characteristic is necessarily conclusive. Large cells can be prokaryotic, mineral crystals can imitate biological shapes and geological alteration can create misleading structures. The strongest identifications therefore combine morphology, chemistry, repeated occurrence and environmental context.

Even when a fossil can confidently be identified as eukaryotic, its precise relationship to modern organisms may remain uncertain. Many organic-walled microfossils are consequently described by form rather than assigned prematurely to animals, plants, fungi or a particular group of protists. This caution is a strength of palaeontology, not a weakness: conclusions are calibrated to the evidence available and revised when better specimens or analytical techniques become available.

Further information: Susannah M. Porter, “Insights into eukaryogenesis from the fossil record”; Ross P. Anderson and colleagues, “Proterozoic microfossils continue to provide new insights into the rise of complex eukaryotic life”.

For creationists, the timescale alone is fatal. The rocks being examined are hundreds of millions to more than a billion years older than the entire Universe is supposed to be according to a literal reading of Genesis. More importantly, they preserve an ordered history of biological and environmental change that bears no resemblance to a six-day creation followed by a recent global flood.

The cellular innovation behind complex life

A eukaryotic cell is fundamentally more internally organised than a bacterial or archaeal cell. Its DNA is enclosed within a nucleus, while specialised compartments called organelles perform particular functions. Among the most important of these are mitochondria, which use oxygen to release energy from food and make energy-intensive forms of cellular organisation possible.

Refuting Creationism - Rationalising The Complex Hominin Taxonomy

Evolution is a process not an event

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Where does red become blue?

Why it might be time to rethink the human family tree.

Taxonomy is an indispensable tool for organising the living world, but it can also create a misleading impression of nature divided into sharply separated compartments. The familiar Linnaean hierarchy was devised in a pre-evolutionary age, principally to classify organisms as distinct types. It was not designed to accommodate fragmentary snapshots of populations undergoing continuous change over millions of years.

That problem becomes particularly acute in palaeoanthropology. Fossils do not come with labels identifying their species and genus, and palaeoanthropologists cannot test whether their owners could have interbred. They must infer relationships from incomplete and often distorted remains, sometimes consisting of little more than a few teeth or part of a jaw. They must then assign those remains to discrete taxonomic boxes, even though evolution within each lineage was continuous, while populations were also branching, diverging, coexisting and sometimes exchanging genes.

The boundary traditionally drawn between Australopithecus and Homo has always seemed especially arbitrary. It gives the impression that, at some point between the two, evolution took a sudden stride and produced something qualitatively different: a creature sufficiently human to be admitted into our genus. In reality, the characteristics once used to define Homo did not appear together as a package. Bipedalism preceded substantial brain enlargement by millions of years; tool use is no longer regarded as the exclusive preserve of Homo; and fossils repeatedly present mosaics of supposedly “primitive” and “advanced” features.

Nor is there a universally objective amount of anatomical difference that separates one genus from another. A genus is a humanly constructed rank, not something that can be excavated from the ground alongside the fossil. Drawing a firm boundary across a gradually changing lineage can therefore exaggerate the differences on either side of it, artificially turning a succession of small evolutionary changes into an apparent leap.

This is the problem addressed by Monash University palaeoanthropologist Dr Ian Towle in a new paper, Clades, grades, and the genus problem: A case for revising hominin taxonomy, published in the American Journal of Biological Anthropology. Towle proposes expanding the genus Homo to include the species currently assigned to Australopithecus and Paranthropus—in effect placing the closely related hominins of the past four or five million years within one broadly defined genus.

Refuting Creationism - How Flightless Beetles Evolved On Japanese Islands

Carabus blaptoides

By Adan - Photo taken by Adan at Sendai Miyagi, Japan., CC BY-SA 3.0, Link

Reach in or crush the shell? A flightless snail-hunting beetle evolved different body shapes even without a sea barrier | EurekAlert!

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Phylogenetic relationships and geographic distribution of Carabus blaptoides

Junji Konuma

Islands have repeatedly provided some of the clearest demonstrations of evolution in action. The most famous example is, of course, Darwin’s finches, whose differently shaped beaks reflect adaptation to different foods in the Galápagos. More recently, as I described in an earlier article about “Darwin’s daisies”, the Galápagos plant genus Scalesia has diversified from a common ancestor into forms with different growth habits and leaf shapes suited to different island environments.

Now scientists studying the Japanese Archipelago have uncovered another striking example of the same fundamental evolutionary process—this time involving flightless beetles and the land snails they eat.

In a paper published in the Biological Journal of the Linnean Society, Junji Konuma of Toho University, Nobuaki Nagata of Japan’s National Museum of Nature and Science, and Teiji Sota of Kyoto University describe the evolutionary diversification of the snail-eating ground beetle Carabus blaptoides. The species is distributed across the Japanese islands and has diversified into eight recognised subspecies.

Because the beetles’ hindwings are reduced, they cannot fly and must disperse on foot. Seas therefore isolate populations on different islands, while sheer distance, topography and environmental variation can restrict movement even between populations on the same large island. This reduced gene flow allows populations to respond independently to local ecological conditions—the familiar starting point for adaptive divergence and, eventually, speciation.

The principal selective pressure appears to be sitting on the beetles’ dinner plate—or, more accurately, retreating into its shell. Different regions of Japan contain different assemblages and sizes of land snails, particularly species of Euhadra and Satsuma. Beetles living where large snails predominate tend to have long, narrow heads and thoraxes. This slender form allows a beetle to push its head deeply into a large shell and reach the animal inside.

Refuting Creationism - How Death Stalked South America In The Form Of Giant Crocodylians - Over 10 Million Years Before 'Creation Week'

[caption]

[credit]

Reconstruction of Purussarus neivensis attacking Pericotoxodon platignathus.

Image: Miguel Hernandez.

Giant crocodylians dominated the food chain in Miocene South America | University of Helsinki.

If the Young-Earth creationist claim that there was no death, suffering or predation before Eve’s supposed ‘sin’ were true, four fossil specimens preserved in museum collections in Colombia should not exist. They are the remains of large herbivorous mammals bearing punctures and other damage attributed to the teeth of a giant crocodylian—and they are between approximately 10.5 and 16 million years old.

In other words, these fossils are not merely the remains of animals that lived and died millions of years before there were humans to commit any biblical ‘sin’. They preserve physical evidence of animals attacking—or, at the very least, feeding upon—other animals in a functioning predator–prey ecosystem more than a thousand times older than the entire universe imagined by Young-Earth creationists.

The evidence is described by Oscar E. Wilson of the University of Helsinki and Jorge W. Moreno-Bernal in a paper recently published in the Journal of Vertebrate Paleontology. The researchers examined four specimens belonging to three species of large, now-extinct South American ungulates from the celebrated La Venta fossil assemblage of Colombia: the toxodontid Pericotoxodon platignathus and the astrapotheres Xenastrapotherium kraglievichi and Granastrapotherium snorki.

The skulls and jaws bear puncture marks and, in some cases, substantial deformation caused by a powerful bite. From the size and shape of the marks, together with the force apparently needed to produce the damage, Wilson and Moreno-Bernal identify the most likely culprit as Purussaurus neivensis, an enormous relative of modern caimans that may have reached about seven metres in length and weighed approximately 1,800 kilograms.

Middle Miocene South America contained an ecosystem unlike anything living today. The continent’s long geographical isolation had allowed native mammals—including toxodontids, astrapotheres, ground sloths and glyptodonts—to diversify independently. Around the immense tropical wetlands lived giant snakes, flightless predatory ‘terror birds’, terrestrial crocodyliforms and several kinds of aquatic crocodylian. Because large mammalian carnivores were comparatively scarce, reptiles such as Purussaurus occupied the major apex-predator niches.

Earlier studies had inferred this ecological role from the animals’ size, anatomy and the composition of the La Venta fauna. The newly reported bite marks provide direct physical evidence that giant crocodylians interacted with—and probably preyed upon—some of the ecosystem’s largest herbivorous mammals. Purussaurus may therefore have helped to regulate herbivore populations, much as large predators influence prey populations in modern ecosystems.

For creationists, the problem could hardly be clearer. These animals lived, competed, killed, fed, reproduced and became extinct millions of years before any known hominin existed, let alone the mythical couple blamed in Genesis for introducing death into the world. Even if an individual bite mark resulted from scavenging rather than an actual attack, that alternative still requires a dead animal, a flesh-eating crocodylian and an established ecological system based partly upon the consumption of carcasses. It offers no refuge for the claim that the pre-Fall world was free from death and carnivory.

Refuting Creationism - Transformation of the Northwest African Landscape - Over 24 Million Years

24 million Years ago

5.3 million years ago

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Northwest Africa, 24 Million years ago.

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African grasslands became widespread over five million years earlier than previously known | EurekAlert!

To anyone familiar with Africa today, its extensive grasslands and savannahs can seem almost timeless: landscapes of grasses, scattered trees, grazing herbivores, predators and recurrent fires. But, like every modern ecosystem, the African savannah has a history. It was not created fully formed, stocked with its present collection of plants and animals, during a mythical creation week a few thousand years ago. It developed through a succession of environmental and evolutionary changes extending over tens of millions of years.

Some of that history is preserved not on the African continent itself, where erosion and geological disturbance have left gaps in the terrestrial record, but beneath the neighbouring Atlantic Ocean. Plant waxes blown from the land settled on the sea surface and were incorporated into sediments accumulating slowly on the ocean floor. Layer upon layer, these sediments preserved a chemical record of the vegetation growing in north-west Africa at different times.

Now, Anna K. Schartman, Pratigya J. Polissar and Caroline A. E. Strömberg have used these molecular fossils and their carbon-isotope composition to reconstruct some 24 million years of ecological change. Their findings are reported in an open-access paper, “The origin and development of the Miocene northwest African savanna”, published in the Proceedings of the National Academy of Sciences.

The researchers found that the region’s closed forests and woodlands began giving way to a much more open ecosystem about 15–14 million years ago—approximately five million years earlier than earlier regional reconstructions had suggested. This first open landscape was not equivalent to the modern African savannah. It was rich in C₃ grasses and had no close modern counterpart. The familiar C₄-grass savannah developed later and in stages, with its most rapid expansion occurring between about 7.4 and 6.4 million years ago.

This does not conflict with research publicised by UC Santa Cruz in 2023, which found locally abundant C₄ grasses in parts of eastern Africa between about 21 and 16 million years ago. That earlier research examined terrestrial fossil sites in Kenya and Uganda; the new study reconstructs regional vegetation in north-west Africa from wind-blown plant waxes preserved in marine sediments. Together, the studies show that Africa did not undergo a single, continent-wide transformation. Different mixtures of forest, woodland and grassland appeared in different regions at different times.