Refuting Creationism - An Ichthyosaur from 200 Million Years Before 'Creation Week'

Artist’s interpretation of Eurhinosaurus mistelgauensis on 'belemnite battleground'.

Credit: Andrey Atuchin.

Eurhinosaurus mistelgauensis specimen from the Urwelt-Museum Oberfranken on a belemnite battleground. The fossil plate is about 4 m long.

Credit: Spicher et al (2025).

New Jurassic ichthyosaur species discovered in Mistelgau

It's shaping up to be another bad week for creationism, with the evidence for evolution on an old Earth continuing to accumulate, and evidence against any intelligence being involved in its evolution growing unabated. There is even a paper describing how and when Earth was really formed, and the contrast between that reality and the Bible’s version could hardly be greater.

This article looks at just one of these developments (more will follow). From the perspective of evolutionary biology, it is not especially remarkable—simply the description of a new species of extinct ichthyosaur, Eurhinosaurus mistelgauensis, from the Lower Jurassic (around 200 million years ago).

But for creationism, it serves as yet another stark reminder of how wrong the biblical creation story and timeline are. To put it bluntly, this fossil would not exist if the Bible’s story were true. It doesn’t take a genius to see how the fact of its existence bears on debates about the truth or falsity of Genesis—though creationists appear to struggle with this basic deductive logic.

Refuting Creationism - A Newly-Identified Dinosaur From About 220 Million Years Before 'Creation Week'

Reconstruction of Newtonsaurus cambrensis in its natural setting

AI-generated (ChatGPT 5)

September: Newtonsaurus identification | News and features | University of Bristol

A newly-identified dinosaur from the Late Triassic of Wales has turned out to be hiding in plain sight. The fossil, discovered in 1899 and displayed for years in the National Museum of Wales, has only now been correctly recognised thanks to modern imaging technology unavailable to earlier researchers.

Originally described by Edwin Tully Newton in 1899 as Zanclodon cambrensis, the specimen has now been reclassified by a team of palaeontologists led by Owain Evans of Bristol University. Since the name Zanclodon is no longer used for early reptiles, the team have given it a new name: Newtonsaurus.

As always, discoveries like this present a problem for creationists. Fossils of species that lived tens or even hundreds of millions of years ago sit uneasily with their narrative that all life was magically created just a few thousand years ago. To preserve that story, they are forced into feats of mental gymnastics — whether by bearing false witness against scientists, rejecting well-established dating techniques, or simply dismissing the evidence outright as “wrong.”

The rocks, however, are not so easily ignored. Unlike ancient manuscripts, said to have been dictated by a god to prophets and accepted only on faith, the fossil record is physical, testable, and open to constant re-examination. Evidence can be checked, rechecked, and reassessed as methods improve — something faith alone cannot provide.

Refuting Creationism - A 108-Million-Year-Old Fossil From Mongolia Fills Another Gap.

Reconstruction of a pachycephalosaur

AI-generated image (ChatGPT 5)

Young Zavacephale duel for territory along a lakeshore 108 million years ago.

Image: Masato Hattori

‘Teen’ Pachycephalosaur Butts Into Fossil Record | NC State News

Here we have another of those regular discoveries which, according to the press, supposedly means history will need to be “re-written” — something creationists, always looking for a stick to beat science with, will assume means the whole of history, because science has got everything wrong yet again. Unlike their religion, of course, which — so they claim — has never got anything wrong and is therefore eternally true, including the parts about a six-day creation 6,000–10,000 years ago, a global flood which left no evidence, and a universe consisting of a small, flat planet with a dome over it.

In reality, this is merely journalistic hyperbole designed to draw the reader in — or, in the case of creationists, to be seized upon as ‘scientific’ evidence that science is fatally flawed.

The “re-written” part of history is simply the bit about which we previously had no information. The process is not one of tearing up the past but of filling a gap in our knowledge and thereby arriving at an account closer to reality. In this case, “re-writing the history books” will mean telling a more complete history of a group of dinosaurs. The discovery in question is a 108-million-year-old adolescent pachycephalosaur fossil found in the Gobi Desert, Central Asia. Being both the oldest (by about 15 million years) and the most complete skeleton of this group of dinosaurs yet discovered, it provides crucial information about their origins.

Refuting Creationism - Dinosaur Eggs From 85 Million Years Before 'Creation Week'

Egg clutch sampled for chronological studies.

Credit Dr. Bi Zhao

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Dinosaur egg fossil sampled for geochronology.

Credit: Dr Bi Zhao

Newly dated 85-million-year-old dino eggs could improve understanding of Cretaceous climate

The dating of a clutch of fossil dinosaur eggs will leave creationists scrambling for excuses to dismiss the evidence and cling to the childish notion that Earth is only 6,000–10,000 years old, created ex nihilo by magic, with all extant and extinct species brought into existence without ancestors just a few days later. In other words, this discovery is yet another small addition to the mountain of evidence showing that the biblical creation story was the work of ignorant Bronze Age people trying to make sense of the world around them, not the word of an omniscient creator god who would have known better.

An added problem for creationists is that the research team used a new method of dating the eggs based on measuring when the eggshell itself formed, rather than relying solely on dating the rock in which the eggs were embedded. The difficulty with the latter approach is that, while it gives the age of the surrounding rock, the mineral grains in that rock may predate the eggs and could have been transported there by water or wind.

The new technique is conceptually similar to the uranium–lead (U–Pb) method used to date zircon crystals in volcanic tuff. Tiny amounts of uranium, which readily substitute into the crystal lattice, are incorporated when the zircon forms, but lead is excluded. Over time, uranium isotopes decay into stable isotopes of lead. Thus, any lead present within a zircon crystal must have come from radioactive decay, and by measuring the ratio of uranium to lead isotopes, scientists can calculate the crystal’s age with high precision.

A very similar process occurs in the carbonate of dinosaur eggshells: uranium is incorporated during formation, but lead is excluded. Measuring uranium–lead isotope ratios in the shell carbonate therefore provides a direct and highly accurate age for the eggs themselves, leaving little room for error.

Refuting Creationism - What Dinosaur Teeth Tell Us About Life - From 150 Million Years Before 'Creation Week'

Giraffatitan

AI-generated image (ChatGPT 5)

Photo of teeth in a jaw section of Giraffatitan from Tanzania (Museum für Naturkunde Berlin, MB.R.2180.20.5). The light-coloured area is the dentin, which has been exposed by tooth wear.

Image Credit: Jan Kersten, Freie Universität Berlin, Fachrichtung Paläontologie.

What Dinosaur Teeth Reveal About Life 150 Million Years Ago - Information for Media and Journalists | Freie Universität Berlin

An international team of researchers, led by Dr Daniela E. Winkler (postdoctoral researcher at Kiel University), Dr Emanuel Tschopp (visiting scientist at the Leibniz Institute for the Analysis of Biodiversity Change and research associate at Freie Universität Berlin), and André Saleiro (PhD student at NOVA University Lisbon), has shed new light on the diet and movements of the 150-million-year-old long-necked dinosaur, Giraffatitan.

By using high-resolution microscopy to examine patterns of microscopic wear on fossilised teeth, the team could reconstruct not only what Giraffatitan ate, but also how it foraged and where it roamed. The results show that these enormous sauropods fed on a wide range of vegetation, from soft leaves to tougher plant material, indicating a flexible feeding strategy. The wear patterns also suggest that the animals migrated across different habitats, rather than remaining in one area, allowing them to exploit seasonal changes in plant availability. This paints a picture of a highly adaptable browser, capable of sustaining its gigantic size by ranging widely across the Jurassic landscape.

In many ways, their lifestyle resembles that of today’s elephants or giraffes, which travel long distances to reach food and switch between different types of vegetation depending on what is available. Like elephants stripping branches or giraffes plucking leaves from the tops of trees, Giraffatitan used its immense neck to access food that other animals could not, helping to reduce competition and maintain the balance of its ecosystem.

They also represent an interesting example of convergent evolution where two unrelated species, in this case a dinosaur and giraffes, converge on the same solution to the same environmental problem - how to reach the leaves at the top of tall trees, so avoiding competition with other browsing animals - long necks and long front legs.

As ever, such discoveries are impossible to reconcile with creationist notions of a young Earth, supposedly only 6,000–10,000 years old. Yet this is merely one more example of the widening gulf between the reality uncovered by science and the superstitions preserved in ancient texts. These texts, after all, were written by Bronze Age pastoralists who imagined the universe as a flat disc beneath a dome, bounded by the few square miles they could walk in a couple of days across the Canaanite hills.

Refuting Creationism - Another Fossil; Another Thorny Problem for Creationists

Artist's impression of Spicomellus afer

Credit: Matt Dempsey

Fossils of S. afer

© The Trustees of the Natural History Museum, London

“Bizarre” armoured dinosaur, Spicomellus afer, had spikes sticking out from its neck, fossils show - University of Birmingham

A newly-identified bizarre dinosaur fossil from Morocco has presented creationists with yet another thorny problem to ignore.

It is that of an ankylosaur from early in the evolutionary history of that group. Not only is its great age a problem for those who believe Earth was magicked into existence by a god with all living things fully formed and an environment perfectly tuned for life (i.e. human life — supposedly the god’s favourite), but at 165 million years old it comes from the vast span of Earth’s pre-“Creation Week” history — that 99.9975% of the planet’s history which creationists pretend never happened. This is, in fact, the oldest ankylosaur yet discovered.

Unlike later ankylosaurs, however, this one had long spikes firmly attached to its bones. These appear to have been lost as the group evolved, showing relatively rapid change. That in itself runs counter to the creationist dogma that evolution cannot proceed by loss of genetic information and must always involve increasing complexity for it to be “real” evolution. This claim, like so many creationist assertions, ignores abundant evidence — such as the reduction in genome size and anatomical complexity in many endoparasites.

Now they have yet another example to ignore while busily constructing their infantile strawman versions of evolution to attack.

The discovery by palaeontologists co-led by Professor Susannah Maidment of Natural History Museum, London, and the University of Birmingham, has just been reported in Nature and is explained in a news item from the University of Birmingham and an accompanying YouTube video:

Creationism Crushed - By Big Biting Dinosaurs

Dinosaur bite illustrations.

Rowe and Rayfield, Current Biology (2025)

Gigantic, meat-eating dinosaurs didn’t all have strong bites | EurekAlert!

Creationists will likely dismiss the recent paper in Current Biology because, as is common in creationist psychology, any scientific evidence contradicting their fundamental beliefs is either ignored, misrepresented, or actively denied—particularly if it suggests their views should be reconsidered.

The study by Andre J. Rowe and Emily J. Rayfield of the University of Bristol (UK) demonstrates that, during the long stretch of Earth’s history predating creationist timelines, giant carnivorous dinosaurs evolved markedly different jaw mechanics to tackle prey—leading to distinct ecological roles. For example, crushers such as Tyrannosaurus rex developed jaws optimised for forceful crushing, akin to crocodilians, whereas slashers - other large theropods such as allosaurids or spinosaurs - developed weaker jaws tailored to ripping and slashing flesh, like modern Komodo dragons [1.1].

This divergence in feeding mechanics underscores a fundamental principle in evolutionary biology: adaptive radiation and allopatric speciation — whereby offspring inheriting intermediate jaw characteristics (neither fully adapted for crushing nor ripping) would likely be at a disadvantage, reducing their reproductive success. Over time, this selective pressure fosters reproductive barriers and drives lineages apart.

Creationism Refuted - How The Survivors of a Mass Extinction Evolved Into Dinosaurs

Euparkeria capensis, a small, 60 cm long reptile from the early Triassic period (245 - 237 million years ago).

Credit: Taenadoman, 2011
via Wikimedia Commons
CC A-SA 3.0

Triassic reptiles took 10,000 mile trips through “hellish” conditions, study suggests - University of Birmingham

Contrary to the child-like naivety and carefully cultivated ignorance of creationists, Earth is not — and never has been — a paradise perfectly designed for life, let alone tailor-made for humans. In reality, the vast majority of Earth's history — around 99.9975% of it — took place long before creationists believe the planet even existed, during which time the environment has frequently become so hostile that mass extinctions wiped out the majority of living species. Life as we know it today descends from the lucky few that managed to survive and adapt to radically altered conditions.

One of the most devastating of these extinction events was the end-Permian climate catastrophe, during which one group of reptiles — the archosauromorphs — managed to endure. From this resilient lineage emerged the dinosaurs, who would go on to dominate the planet until they too were annihilated by a cataclysmic meteor impact 66 million years ago.

While palaeontologists have long known about the survival and evolutionary significance of archosauromorphs, a lingering mystery remained: how did they manage to disperse across vast "dead zones" of the tropics, where temperatures were thought to be lethally high? A new study by researchers from the University of Birmingham and the University of Bristol has now shed light on this question. Their findings have been published, open access, in Nature Ecology & Evolution.

Refuting Creationism - What T. Rex's Ancestors Were Doing More Than 70 Million Years Before 'Creation Week'.

T. rex’s direct ancestor crossed from Asia to North America | UCL News - UCL – University College London

This artwork illustrates the disparity of the northern and southern hemisphere’s evolution of terrestrial Cretaceous faunas after the Cretaceous Thermal Maximum. On the left, End Cretaceous Southern Hemisphere (Western Gondwana) became dominated by megaraptorid theropods and titanosaur sauropods. The centre of the piece summarises the extinction event of terrestrial fauna at the Cretaceous Thermal Maximum, where the apex predators the carcharodontosaurids and allosaurs went extinct and tyrannosauroids (including megaraptoran and the ancestors of Tyrannosaurus rex) were small. On the right, the end Cretaceous northern hemisphere fauna dominated by tyrannosaurids (such as Tyrannosaurus rex), hadrosaurs and ceratopsian ornithischian dinosaurs. The environment also became more mesic compared to the more semi-arid seasonal environment earlier in the Cretaceous.

Credit: Pedro Salas and Sergey Krasovskiy.

One of the major challenges for creationism is how to ignore the overwhelming volume of evidence that contradicts it—especially from the vast span of Earth’s pre-'Creation Week' history, during which 99.9975% of geological time unfolded. Even allowing for their standard claim that scientists fake their dates and Earth is really only a few thousand years old, there is a vast amount of history to compress into so short a timeline.

During that immense period, something remarkable was happening: a distant ancestor of Tyrannosaurus rex, destined to become one of the most formidable land predators the planet has ever seen, was making its way across a land bridge from Asia into North America.

That’s the conclusion of a new study led by researchers at University College London (UCL), recently published in Royal Society Open Science. The team found that this transcontinental migration—via the Beringian land bridge over 70 million years ago—marked a key moment in the evolution of tyrannosaurids. They also noted a rapid increase in body size that appears to have coincided with a global cooling event following a climatic peak around 92 million years ago. The study was a collaboration between scientists from UCL and the universities of Oxford, Pittsburgh, Aberdeen, Arizona, Anglia Ruskin, Oklahoma, and Wyoming.

Refuting Creationism - Beetles Were Feeding on Dinosaur Feathers - 100 million Years Before 'Creation Week'

Moult remains of feather-feeding beetle larvae intimately associated with downy feather portions from an unidentified theropod dinosaur in Early Cretaceous amber of Spain. Insets show the head with powerful mandibles of one of the larval moults (top) and the pigmentation pattern of feather second order branches (bottom), with the main stem of one feather at the right of the amber fragment. The length of the amber fragment is 6 millimetres across.

Image credit: CN IGME-CSIC.

Fossils reveal a 100-million-year-old relationship between feathered dinosaurs and feather-feeding beetles | University of Oxford

Isolated moult of the feather-feeding beetle larva found in the Spanish amber outcrop of Rábago/El Soplao, with detail of its powerful mandibles (right). Length of the moult is less than two millimetres.

Image credit: CN IGME-CSIC.

To normal people, the discovery of feather-eating beetles and feather fragments in 105-million-year-old amber, 30 million years before there were birds might be a clue that something had feathers before bird had them, suggesting that birds might have evolved from whatever that was.

Not so, creationists, however. Creationists conclude that any evidence that doesn't agree with them must be wrong because their evidence-free dogma is sacred and therefore uninfluenced by real-world evidence.

So, the following is just something else for creationists to ignore while they pretend to know better than the experts who have, unlike creationists, actually studied the subject.

It is news that a study, co-led between the Geological and Mining Institute of Spain of the Spanish National Research Council (CN IGME-CSIC) and Oxford University Museum of Natural History (OUMNH) has shown that beetles fed on the feathers of dinosaurs about 105 million years ago. This is based on an analysis of spectacular fossil amber fragments, from the locality of San Just in north-eastern Spain, revealed moults of tiny beetle larvae tightly surrounded by portions of downy feathers.

The feathers belonged to an unknown theropod dinosaur that lived around 105 million years ago, during the Early Cretaceous. This means that the feathers could not have come from a ‘modern bird’ species, since current evidence indicates that this group appeared about 30 million years later in the fossil record, during the Late Cretaceous.

Refuting Creationism - Even a 10 Year-Old Can Do It - 200-Million Year-Old Dinosaur Tracks In South Wales

200-million-year-old dinosaur tracks in red sandstone, Lavernock Point, South Wales

Illustrations of how a camelotia may have looked like are rare, but experts think it closely resembled the massospondylus, shown here.

Schoolgirl's dinosaur footprint find on Vale of Glamorgan beach - BBC News

Ten-year-old Tegan went looking for fossils on a South Wales beach with her mother, Clair, and found something completely unexpected - a set of footprints made by a massive dinosaur 200 million years ago.

These have been identified by dinosaur expert, Cindy Howells, from the National Museum Wales, as almost certainly the tracks of a sauropodomorpha. The tracks were in a red sandstone 'pavement' on the beach at Lavernock Point between Cardiff and Barry on a stretch of the Glamorgan Heritage Coast known to be a prehistoric hotspot.

Refuting Creationism - The Mass Extinction, 66 million Years Before 'Creation Week'

Artist’s rendition of the asteroid entering the atmosphere. 66 million years ago.

Tracking down the asteroid that sealed the fate of the dinosaurs

If there is anything guaranteed to have creationists metaphorically, if not actually, screwing up their eyes, putting their hands over their ears and jumping up and down shouting "'Tisn't! 'Tisn't! 'Tisn't!" its news about the mass extinction 66 million years before 'Creation Week' that exterminated all but the non-avian dinosaurs and the early mammals and about 75% of all other species.

This event reminds them not only that Earth is very much older that their cult requires them to believe but also that Earth is not the 'finely-tuned' haven for life that their belief in a perfect creator requires them to believe. Instead, Earth is very old and subject to unpredictable catastrophes, not the least of which are cosmological events such as meteor strikes and the consequential mass extinctions.

Refuting Creationism - A Burrowing Dinosaur - 99 Million Years Before 'Creation Week'

Fona herzogae.

Credit: Jorge Gonzalez.

Fona herzogae.

Credit: Jorge Gonzales

Life Underground Suited New Dinosaur Fine | NC State News

If you want to leave a fossil as evidence of your existence, live, or at least die, in a burrow.

If you want to refute creationism, arrange to die 99 million years before they believe the Universe existed.

That's what an otherwise unremarkable dinosaur that was about the size of a large dog, contrived to do in what is now Utah, USA. It, and its relatives, because so many of them died in their borrows, are preserved in exception detail compared to species that lived above ground where their bodies would have been scavenged and destroyed before they could be fossilised.

Creationism in Crisis - UK's Most Intact Dinosaur Fossil Was Living 125 Million Years Before 'Creation Week'

Jeremy Lockwood at the excavation site,
Compton Bay, Isle of Wight]

An artist’s impression of Comptonatus chasei.

Image credit: John Sibbick

Research reveals the most complete dinosaur discovered in the UK in a Century | University of Portsmouth

The fossil remains of a dinosaur, discovered in the cliffs of Compton Bay, Isle of Wight, England, have been shown to be a species new to science. The fossils were discovered in 2013 by the late fossil collector Nick Chase, who sadly died of cancer before his finds could be fully analysed. Nick Chase had a record of fossil discovery, including the most complete Iguanodon skull ever found, yet never had a new species named after him

That has now been rectified by retired GP and PhD student at the School of the Environment, Geography and Geosciences, University of Portsmouth, UK, Jeremy Lockwood, who helped with the dinosaur's excavation and has spent years analysing it to determine that it is a new species which he has named Comptonatus chasei. It has proven to be the most intact dinosaur ever discovered in Britain.

Together with David Martell, also of the School of the Environment, Geography and Geosciences, University of Portsmouth and Susannah Maidment of the Fossil Reptiles, Amphibians and Birds Section, Natural History Museum, London, UK, Dr Lockwood has published his findings, open access, in the Journal of Systematic Palaeontology. Their work is also explained in a University of Portsmouth press release:

Creationism in Crisis - A Newly-Discovered Dinosaur, Lokiceratops - From 78 Million Years Before 'Creation Week'

Reconstruction of Lokiceratops in the 78-million-year-old swamps of northern Montana

Artwork by Fabrizio Lavezzi
© Evolutionsmuseet, Knuthenborg

Newly discovered dinosaur Lokiceratops boasts big, blade-like horns - Warner College of Natural Resources

Reconstruction of Lokiceratops in the 78-million-year-old swamps of northern Montana, as two Probrachylophosaurus move past in the background.

Artwork by Fabrizio Lavezzi © Evolutionsmuseet, Knuthenborg

Colorado State University affiliate faculty member Joseph Sertich and University of Utah Professor Mark Loewen, have identified and named a new species of dinosaur that lived in Northern Montana.

Like almost everything that ever lived, this dinosaur, Lokiceratops, lived in the 99.99975% of history that happened before creationists like to imagine the universe was created. It lived a mere 78 million years before the mythical creation week, to be precise.

An interesting feature of this species - one of a number that appear to have evolved rapidly in the region - is the large 'ornamental' horns that may have been used in courtship, implying female sex-selection played a part. Female sex-selection is a known driver of rapid speciation because it produces genetic isolation and forms an important pre-zygotic barrier to hybridization, just as display and sex-selection does in many birds today.

This could account for the apparent proliferation of these types of dinosaurs.

Creationism in Crisis - How Dinosaurs Evolved Feathers

Latest News and Views from University College Cork

Psittacorus (reconstruction)

Artwork by Walter Myers

This paper is enough to send a dedicated creationist disinformation specialist into intellectual summersaults. On the one hand, they hate the fact that dinosaurs lived so long ago and are evidence of life on earth tens and hundreds of millions of years ago, so they bend over backwards to prove they were around just a few thousand years ago, and then, horror of horrors, along come some clever scientists and show evidence that some dinosaurs even evolved into birds!

And now, courtesy of Palaeontologists at University College Cork (UCC) in Ireland , we have evidence of the transition from scales to feathers in pre-avian dinosaurs.


But it gets even worse! Creationists frauds have ben claiming for several years now that 'fossilised' soft dinosaur tissues prove they were just a few thousand years old because, despite the perfectly rational explanation of how 'soft' tissues can be preserved for many millions of years in the right circumstances, like the presence of iron, the evidence of this transition from scales to feathers would found in fossilised soft tissue!

So, a creationist disinformation specialist must now argue that fossilised dinosaur soft tissues don't exist, and when they do, they prove dinosaurs lived recently. One problem they face is that the fossilised skin isn't skin at all, or even the fibrous protein parts of skin; it has been entirely mineralised aa silicate, preserving only the morphology, including the surface patterning - which is where the evidence lies.

The University College Cork scientists have just published their findings, open access, in Nature Communications and in a UCC news release:

Creationism in Crisis - Dinosaurs Evolved Warm-Bloodedness 180 Million Years Before 'Creation Week'

Artist’s impression of a dromaeosaur, a type of feathered theropod, in the snow. This raptor was a relative of Velociraptor.

Davide Bonadonna/Universidade

First ‘warm-blooded’ dinosaurs may have emerged 180 million years ago | UCL News - UCL – University College London

Of all the different orders of living organisms' only mammals and birds today are warm-blooded, i.e., they are able to maintain a body temperature, within a certain range of ambient temperatures, by either producing heat or losing it, as necessary.

It might be thought that this indicates that the ability evolved in a common ancestor but of the ancestors of birds, the evidence suggests that many dinosaurs were cold-blooded like today's reptiles, and mammals are descendants of an earlier, pre-dinosaurian reptiles, so these similar processes for maintaining the body temperature may be more a matter of convergence than common ancestry.

Do mammals and birds use the same method to maintain their body temperature, and if not, how do they differ? Mammals and birds both maintain their body temperatures through endothermy, meaning they generate and regulate heat internally to keep their body temperatures stable. However, there are differences in how they achieve this due to variations in their physiology and behaviors. Here’s an overview of the similarities and differences:

Similarities in Temperature Regulation

1. Metabolic Heat Production:
   • Both mammals and birds generate heat through metabolic processes. This involves breaking down food to produce energy, with heat being a byproduct.
2. Insulation:
   • Both groups have evolved insulating layers to retain heat. Mammals have fur or hair, while birds have feathers. These layers trap air and provide a barrier against the cold.
3. Shivering Thermogenesis:
   • Both can generate additional heat through shivering, which involves rapid muscle contractions that produce heat.
4. Behavioral Adjustments:
   • Both mammals and birds engage in behaviors to manage their temperature, such as seeking shade or shelter, sunning themselves, or altering their activity levels based on the ambient temperature.

Differences in Temperature Regulation

1. Physiological Mechanisms:
   • Sweating and Panting: Mammals often use sweating and panting to cool down. Sweat glands secrete moisture that evaporates, taking heat away from the body. Dogs, for instance, pant to evaporate moisture from their respiratory tract. Birds, on the other hand, do not sweat. Instead, they often rely on a behavior called gular fluttering, where they rapidly move the skin in their throat to increase evaporation and cool down.
   • Brown Adipose Tissue (BAT): Many mammals, especially small ones and those living in cold environments, have brown adipose tissue that generates heat through non-shivering thermogenesis. Birds lack this type of tissue.
2. Heat Exchange Systems:
   • Countercurrent Heat Exchange: Birds have highly efficient countercurrent heat exchange systems in their legs and feet, which minimize heat loss. Blood vessels are arranged such that warm arterial blood warms the cooler venous blood returning to the body, conserving heat. While some mammals also use countercurrent heat exchange (such as in extremities), the systems are particularly pronounced and crucial in birds.
3. Basal Metabolic Rate:
   • Birds generally have higher basal metabolic rates compared to mammals of similar size, which means they produce more heat relative to their body size. This higher metabolic rate is partly due to the high energy demands of flight.
4. Hibernation and Torpor:
   • Many mammals can enter states of torpor or hibernation to conserve energy and reduce body temperature during periods of cold or food scarcity. While some birds also enter torpor, true hibernation is rare in birds. Instead, some birds migrate to warmer regions to avoid cold weather.

Behavioral Differences

1. Migration:
   • Migration is a key strategy for many birds to avoid extreme temperatures. While some mammals also migrate, it is far more common and pronounced in birds.
2. Nesting and Roosting:
   • Birds often build insulated nests or seek out warm roosting spots to maintain body temperature, especially during breeding seasons or cold nights. Mammals, on the other hand, may use burrows, dens, or other insulated shelters.

In summary, while both mammals and birds use endothermic processes to maintain their body temperatures, the specific physiological and behavioral strategies they employ can differ significantly due to their distinct evolutionary paths and physical characteristics.

A team of researchers led by University College London (UCL) and Universidade de Vigo, Spain, scientists has concluded that dinosaurs may have evolved warm-bloodedness as long ago as 180 million years ago, some 50 million years after the first dinosaurs evolved.

They concluded this after relating the evolutionary tree of the dinosaurs throughout the Mesozoic era to climate and geographical changes over the same time period and examining 1000 dinosaur fossils.

Their findings are the subject of an open access paper in the Cell Press journal, Current Biology. Their work is also explained in a UCL news release:

The ability to regulate body temperature, a trait all mammals and birds have today, may have evolved among some dinosaurs early in the Jurassic period about 180 million years ago, suggests a new study led by UCL and University of Vigo researchers.

In the early 20^th century, dinosaurs were considered slow-moving, “cold-blooded” animals like modern-day reptiles, relying on heat from the sun to regulate their temperature. Newer discoveries indicate some dinosaur types were likely capable of generating their own body heat but when this adaptation occurred is unknown.

The new study, published in the journal Current Biology, looked at the spread of dinosaurs across different climates on Earth throughout the Mesozoic Era (the dinosaur era lasting from 230 to 66 million years ago), drawing on 1,000 fossils, climate models and the geography of the period, and dinosaurs’ evolutionary trees.

The research team found that two of the three main groupings of dinosaurs, theropods (such as T. rex and Velociraptor) and ornithischians (including relatives of the plant eaters Stegosaurus and Triceratops), moved to colder climates during the Early Jurassic, suggesting they may have developed endothermy (the ability to internally generate heat) at this time. In contrast, sauropods, the other main grouping which includes the Brontosaurus and the Diplodocus, kept to warmer areas of the planet.

Previous research has found traits linked to warm-bloodedness among ornithischians and theropods, with some known to have had feathers or proto-feathers, insulating internal heat.

Our analyses show that different climate preferences emerged among the main dinosaur groups around the time of the Jenkyns event 183 million years ago, when intense volcanic activity led to global warming and extinction of plant groups. At this time, many new dinosaur groups emerged. The adoption of endothermy, perhaps a result of this environmental crisis, may have enabled theropods and ornithischians to thrive in colder environments, allowing them to be highly active and sustain activity over longer periods, to develop and grow faster and produce more offspring.

Dr Alfio Alessandro Chiarenza, first author
Centro de Investigación Mariña
Departamento de Ecoloxía e Bioloxía Animal
Universidade de Vigo, Vigo, Spain

And Department of Earth Sciences
University College London, London, UK.

Theropods also include birds and our study suggests that birds’ unique temperature regulation may have had its origin in this Early Jurassic epoch. Sauropods, on the other hand, which stayed in warmer climates, grew to a gigantic size at around this time – another possible adaptation due to environmental pressure. Their smaller surface area to volume ratio would have meant these larger creatures would lose heat at a reduced rate, allowing them to stay active for longer.

Dr Sara Varela, Co-author
Centro de Investigación Mariña
Departamento de Ecoloxía e Bioloxía Animal
Universidade de Vigo, Vigo, Spain.

In the paper, the researchers also investigated if sauropods might have stayed at lower latitudes to eat richer foliage unavailable in colder polar regions. Instead, they found sauropods seemed to thrive in arid, savannah-like environments, supporting the idea that their restriction to warmer climates was more related to higher temperature and then to a more cold-blooded physiology. During that time, polar regions were warmer, with abundant vegetation. The Jenkyns event occurred after lava and volcanic gasses erupted from long fissures in the Earth’s surface, covering large areas of the planet.

This research suggests a close connection between climate and how dinosaurs evolved. It sheds new light on how birds might have inherited a unique biological trait from dinosaur ancestors and the different ways dinosaurs adapted to complex and long-term environmental changes.

Dr Juan L. Cantalapiedra, co-author
Departamento de Paleobiología
Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain.

The study involved researchers from UCL, University of Vigo, the University of Bristol and the Museo Nacional de Ciencias Naturales in Madrid, and received funding from the European Research Council, the Spanish Ministry of Research, the Natural Environment Research Council and the Royal Society.

Highlights

• Warm-blooded dinosaurs flourished in varied climates.
• Dinosaur groups adapted differently to climate, suggesting diverse thermophysiologies.
• Endothermy in theropods and possibly ornithischians evolved by the Early Jurassic
• Sauropod niche conservatism suggests higher thermal sensitivity and poikilothermy.

Graphical Abstract

Summary

A fundamental question in dinosaur evolution is how they adapted to long-term climatic shifts during the Mesozoic and when they developed environmentally independent, avian-style acclimatization, becoming endothermic.^1,2 The ability of warm-blooded dinosaurs to flourish in harsher environments, including cold, high-latitude regions,^3,4 raises intriguing questions about the origins of key innovations shared with modern birds,^5,6 indicating that the development of homeothermy (keeping constant body temperature) and endothermy (generating body heat) played a crucial role in their ecological diversification.⁷ Despite substantial evidence across scientific disciplines (anatomy,⁸ reproduction,⁹ energetics,¹⁰ biomechanics,¹⁰ osteohistology,¹¹ palaeobiogeography,¹² geochemistry,^13,14 and soft tissues^15,16,17), a consensus on dinosaur thermophysiology remains elusive.^{1,12,15,17,18,19} Differential thermophysiological strategies among terrestrial tetrapods allow endotherms (birds and mammals) to expand their latitudinal range (from the tropics to polar regions), owing to their reduced reliance on environmental temperature.²⁰ By contrast, most reptilian lineages (squamates, turtles, and crocodilians) and amphibians are predominantly constrained by temperature in regions closer to the tropics.²¹ Determining when this macroecological pattern emerged in the avian lineage relies heavily on identifying the origin of these key physiological traits. Combining fossils with macroevolutionary and palaeoclimatic models, we unveil distinct evolutionary pathways in the main dinosaur lineages: ornithischians and theropods diversified across broader climatic landscapes, trending toward cooler niches. An Early Jurassic shift to colder climates in Theropoda suggests an early adoption of endothermy. Conversely, sauropodomorphs exhibited prolonged climatic conservatism associated with higher thermal conditions, emphasizing temperature, rather than plant productivity, as the primary driver of this pattern, suggesting poikilothermy with a stronger dependence on higher temperatures in sauropods.

Chiarenza, Alfio Alessandro; Cantalapiedra, Juan L.; Jones, Lewis A.; Gamboa, Sara; Galván, Sofía; Farnsworth, Alexander J.; Valdes, Paul J.; Sotelo, Graciela; Varela, Sara
Early Jurassic origin of avian endothermy and thermophysiological diversity in dinosaurs Current Biology (2024) DOI: 10.1016/j.cub.2024.04.051

Copyright: © 2024 The authors.
Published by Elsevier. Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)

Dinosaurs have always been a problem for creationists because their existence betrays the fact that the age of Earth as calculated from the Bible geneaolgies is wildly inaccurate by several orders of magnitude, but this paper piles on the agony by showign a clear evolutionary pathway from poikilothermy (cold-bloodedness) to homeothermy (warm-bloodedness) supported by geological, geographical and climatological evidence sometime around 180 million years before the biblical 'Creation Week'.

And it goes without saying that, being biologists, the authors of the paper show no sign of abandoning the TOE in favour of the childish notion of magic creation by an unproven supernatural entity. Indeed, they could scarcely be considered scientists if they included magic and superstition in their explanation for natural phenomena like creationists pseud-scientists are obliged to for contractual reasons.

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