Researchers have identified a new species of early tetrapod from the Lower Permian of Germany. It is a plant-eater, and it has been named Diadectes dreigleichenensis.  The fossils originate from the Bromacker locality in central Germany.  The ancient creatures from the Bromacker locality lived approximately 290 million years ago.  The site is helping palaeontologists to better understand the evolution of herbivory in early vertebrate ecosystems.

Fossil skull material showing the teeth in the jaws and palatal teeth rows. A new species of advanced reptiliomorph has been named (Diadectes dreigleichenensis). Picture credit: Carola Radke, Museum für Naturkunde Berlin.

Picture credit: Carola Radke, Museum für Naturkunde Berlin

Diadectes dreigleichenensis

The lower Permian Bromacker locality, situated in the UNESCO Global Geopark Thüringen Inselsberg – Drei Gleichen, central Germany, represents a unique inland fossil ecosystem that preserves a diverse early tetrapod fauna.  This palaeoenvironment is dominated by advanced reptiliomorphs, land animals that show a variety of amphibian as well as reptilian traits.  Lead author of the study, PhD student Jasper Ponstein (Museum für Naturkunde and the Humboldt-Universität zu Berlin) explained that the research team examined skull and jaw material representing the Diadectomorpha.  The research has been published in the Royal Society Open Science.

The researchers used traditional examination techniques that involved carefully measuring the bones in the skull and jaws and comparing them to specimens in other collections.  In addition, CT scans were undertaken to reveal fine details obscured by matrix.  This research supports the identification of a third species of the group, representing a second species of the genus Diadectes, from Bromacker. This adds to the already diverse fauna of this herbivore-dominated ecosystem.

Since the 1990s palaeontologists have described fossil specimens belonging to the Diadectes genus from the Bromacker site. These specimens had all been assigned to a single species – Diadectes absitus.  Diadectes is a member of the Diadectidae family.  This family of reptilomorphs show both amphibian and amniote characteristics.  They evolved during the Early Carboniferous (Mississippian subperiod), and their fossils are known from America, Asia and Europe. These animals are typically, robust, heavily-built tetrapods.  They had strong, deep jawbones and molar-like teeth adapted to a diet of plants.

Diadectes dreigleichenensis fossil jawbone shown in lateral view. The jaw is robust, and the molar-like teeth are adapted for the efficient grinding of plant material. Picture credit: Carola Radke, Museum für Naturkunde Berlin.

Picture credit: Carola Radke, Museum für Naturkunde Berlin

The Diadectomorpha include the earliest known herbivorous tetrapods, which evolved 305 million years ago in North America during the Late Carboniferous. Through the Late Carboniferous and much of the early Permian, herbivores remained a rare component of their respective ecosystem.

Abundant Early Herbivores

The Bromacker quarry is extremely significant.  It preserves evidence of the earliest ecosystem known in which herbivores were highly abundant.  Palaeontologists consider the Bromacker locality as the first modern ecosystem with a food chain that is recognisable today.  Herbivores make up the greatest proportion of vertebrates present.  In comparison, there are few secondary and apex predators.  The herbivore fossil record at this location includes numerous and exquisitely preserved skeletons of the diadectomorphs Diadectes absitus and Orobates pabsti, the pot-bellied caseid Martensius bromackerensis and the small agile lizard-like bolosaurid Eudibamus cursoris.

Jasper Ponstein outlined how the study was undertaken.  He stated:

“These skulls are preserved with the jaws firmly attached to the rest of the skull. Key features related to feeding, like the tooth row and the shape of the jaw joint, are obscured by the skull.  Through the CT-scans, we could actually reconstruct what these regions look like and compare the different specimens”.

The detailed study of the skull fossils revealed that diadectomorphs have a sinuous row of teeth on their lower jaws.  In addition, there are two rows of conical teeth located on the palate and a long blade-like process connected to the jaw joint.  The teeth in the lower jaw are widely spaced to maximise the available plant grinding surface. The blade-like process of the jaw joint probably played a role in helping to support the jaw whilst plant material was masticated. These adaptations allowed diadectomorphs to more effectively grind vegetation. Furthermore, the powerful CT images revealed a few replacement teeth within the palate. This suggests that diadectomorphs occasionally replaced their palatal teeth as well.

These observations enabled the research team to conclude that there was sufficient variation between the skulls to erect a new species – Diadectes dreigleichenensis.

Ponstein remarked:

“We named the species after UNESCO Global Geopark Thüringen Inselsberg – Drei Gleichen, which also contains the world-famous Bromacker locality. The species name is after Drei Gleichen, which means three of the same, in reference to the seemingly similar looking three diadectids from Bromacker, just like three iconic castles from the Middle Ages, each situated on a hilltop between Gotha and Erfurt within the Geopark.”

Co-author Professor Jörg Fröbisch (Humboldt-Universität zu Berlin) added:

“The ongoing Bromacker project is a prime example of an innovative and interdisciplinary research and science communication program, building on a multiple-decade-long international collaboration.”

Everything Dinosaur acknowledges the assistance of a media release from the Museum für Naturkunde, Berlin in the compilation of this article.

The scientific paper: “A comprehensive phylogeny and revised taxonomy of Diadectomorpha with a discussion on the origin of tetrapod herbivory” by Ponstein, J., MacDougall, M.J., and Fröbisch, J. 2024 published in the Royal Society Open Science.

The award-winning Everything Dinosaur website: Dinosaur Toys and Models.

Researchers have named a new species of iguanodontian dinosaur from fossils found on the Isle of Wight.  The dinosaur has been named Comptonatus chasei.  The fossil material represents the most complete iguanodontian skeleton discovered in the Wealden Group for over a hundred years.  This new taxon has been erected based on numerous unique characteristics (autapomorphies) related to the skull, the straight dentary bone and a markedly expanded pubic hip bone described as being “the size of a dinner plate”.

A view of the head of the newly described iguanodontian Comptonatus chasei. Picture credit: John Sibbick.

Comptonatus chasei

The fossil material is around 125 million years old (Barremian faunal stage). The dinosaur fossils was found in the cliffs of Compton Bay on the Isle of Wight in 2013 by fossil collector Nick Chase, before he tragically died of cancer.  Dr Jeremy Lockwood, helped with the excavation of the bones and teeth. He then spent years carefully comparing these fossils to other Wealden Group iguanodontians before he was confident that these fossils represented a new species.

Dr Jeremy Lockwood walking on the beach in front of the cliffs that mark the excavation site. Picture credit: University of Portsmouth.

Dr Lockwood has become synonymous with Isle of Wight ornithopods along with Professor David Martill (University of Portsmouth) and Professor Susannah Maidment (London Natural History Museum).  These three scientists described Brighstoneus simmondsi, another Isle of Wight ornithopod in 2021.  The discovery of Comptonatus chasei demonstrates that these dinosaurs were particularly diverse during the Barremian to early Aptian faunal stages.

Lateral views of the skulls of three taxa of Isle of Wight iguanodontian dinosaurs. Comptonatus chasei (A), Brighstoneus simmondsi (B) and Mantellisaurus atherfieldensis (C). Picture credit: University of Portsmouth.

Honouring the Late Nick Chase

A total of 149 fossil bones were collected.  The genus name translates as “Compton thunderer”.  This dinosaur was named after Compton Bay where the fossils were found and the “thunderer” element of the genus name relates to the large size of this dinosaur.   Bone histology indicates that the animal was around five or six years old when it died. It is estimated to have weighed around nine hundred kilograms.

The species name honours Nick Chase, winner of the Palaeontological Association’s Mary Anning Award in 2018, who made the initial discovery and through his lifetime contributed enormously to the collections at the Dinosaur Isle Museum on the Isle of Wight, and the Natural History Museum, London.

The late Nick Chase who found the fossil remains in 2013. The species name honours him, a winner of the Palaeontological Association’s Mary Anning Award in 2018, Nick Chase made the initial discovery. During his lifetime he contributed enormously to the study of the dinosaur biota of the Wessex Formation. Picture credit: University of Portsmouth.

Dr Lockwood commented:

“Nick had a phenomenal nose for finding dinosaur bones – he really was a modern-day Mary Anning. He collected fossils daily in all weathers and donated them to museums. I was hoping we’d spend our dotage collecting together as we were of similar ages, but sadly that wasn’t to be the case. Despite his many wonderful discoveries over the years, including the most complete Iguanodon skull ever found in Britain, this is the first dinosaur to be named after him.”

The Comptonatus chasei excavation in 2013. Nick Chase (in the foreground sketching), Steve Hutt (blue jumper), Jeremy Lockwood (wearing gloves), and Penny Newberry examining the exposed fossil material. Picture credit: University of Portsmouth.

Unique Autapomorphies

During the collection and initial preparation it was thought that these fossils represented a Mantellisaurus atherfieldensis. However, a detailed study identified several autapomorphies (unique characteristics) that led to the erection of a new taxon.

Dr Lockwood explained:

“I’ve been able to show this dinosaur is different because of certain unique features in its skull, teeth and other parts of its body. For example its lower jaw has a straight bottom edge, whereas most iguanodontians have a jaw that curves downwards. It also has a very large pubic hip bone, which is much bigger than other similar dinosaurs. It’s like a dinner plate!”

The large pubis bone of Comptonatus pubis. The enlarged blade-like feature of the pubis is a unique characteristic that helped to define this new taxon. Picture credit: University of Portsmouth.

The scientists are uncertain as to why the pubic hip bone is so large. It could have been for muscle attachments indicating that this ornithopod had a different mode of locomotion. Perhaps it could have helped support the large stomach, or played a role in respiration.

The Geological Setting of Comptonatus chasei

Comptonatus chasei and Brighstoneus simmondsi fossils are associated with the Wessex Formation of the Wealden Group.  However, the deposits where Brighstoneous fossils have been found might be two million years older than the strata associated with C. chasei.  Conversely, Mantellisaurus atherfieldensis is geologically younger than Comptonatus.  Mantellisaurus fossils seem confined to the overlying Vectis Formation (Wealden Group).  This means that Comptonatus and Brighstoneus lived during the early Barremian faunal stage of the Cretaceous.  Mantellisaurus lived several million years later (late Barremian).

The scientists state that the Wessex Formation may have supported a greater diversity than previously realised, or that evolutionary and or migratory pressures resulted in faunal turnover. Comptonatus provides further evidence for a greater iguanodontian diversity and it is now unclear as to which iguanodontian taxon or taxa dominated the Wessex sub-basin during the Barremian.  In addition, the researchers postulate that a reassessment of ornithopod fossil material may be required, as with our improved understanding of the differences between these taxa, more new species might be identified.

Isle of Wight Dinosaur Taxa

Despite only four new dinosaur species being described on the Isle of Wight in the whole of the 20th century, there have been eight new species named in the last five years.  A remarkable number of new dinosaur taxa have been described from fossils found on the Isle of Wight. Ornithischians such as Vectidromeus insularis, Brighstoneus simmondsi and Vectipelta barretti have been named.

To read more about Vectidromeus insularis: Vectidromeus – A New Hypsilophodontid.

An article on Brighstoneus simmondsi: A New Iguanodontid from the Isle of Wight.

A scale drawing of the recently described Isle of Wight iguanodontian Brighstoneus.  CollectA added a model of Brighstoneus simmondsi to their CollectA Age of Dinosaur Popular range of figures.  Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

A new, armoured dinosaur from the Isle of Wight described in 2023 (Vectipelta barretti): New Armoured Dinosaur Honours Natural History Museum Professor.

In addition, several theropod dinosaurs have been described including Vectiraptor greeni, Ceratosuchops inferodios and Riparovenator milnerae. Furthermore, there is evidence of a gigantic spinosaurid (the “white rock spinosaurid”). These discoveries suggest that the Wessex Formation supported a greater diversity of dinosaurs than previously realised. It could also indicate a substantial faunal turnover during the deposition of the Wessex Formation deposits.

Ancient relative of Velociraptor from “Dinosaur Isle”: Early Cretaceous Dromaeosaurid from the Isle of Wight.

To read about Ceratosuchops inferodios and Riparovenator milnerae: Two New Spinosaurids from the Isle of Wight.

News about the enormous “white rock spinosaurid”: Super-sized Carnivorous Dinosaur from the Isle of Wight.

Everything Dinosaur acknowledges the assistance of a media release from the University of Portsmouth in the compilation of this article.

The scientific paper: “Comptonatus chasei, a new iguanodontian dinosaur from the Lower Cretaceous Wessex Formation of the Isle of Wight, southern England” by Jeremy A. F. Lockwood, David M. Martill and Susannah C. R. Maidment published in the Journal of Systematic Palaeontology.

The Everything Dinosaur website: Dinosaur Models.

A newly published study led by scientists from the Field Museum in Chicago (USA) includes descriptions of nine new species of fossil grapes.  The paper, published in the journal “Nature Plants” reveals how the extinction of the non-avian dinosaurs may have permitted grape vines to spread and diversify.  Some of the newly described grape taxa are the oldest found to date in the Western Hemisphere.  The fossils were found in Peru, Panama and Columbia and range in age from sixty million years old to around nineteen million years old.  The seeds range in geological age from the Palaeocene Epoch to the Miocene Epoch.

Fossil grape (photograph top left) with computer model generated from CT fossil scans (top right). Line drawings illustrating the fossil by Pollyanna von Knorring (below). Picture credit: Fabiany Herrera.

Picture credit: Fabiany Herrera

Studying Fossil Grapes

These fossil seeds from Central and South America help to show how the grape family (Vitis) spread in the years following the extinction of the dinosaurs.

Lead author of the paper Fabiany Herrera (assistant curator of palaeobotany at the Field Museum in Chicago), commented:

“These are the oldest grapes ever found in this part of the world, and they’re a few million years younger than the oldest ones ever found on the other side of the planet.  This discovery is important because it shows that after the extinction of the dinosaurs, grapes really started to spread across the world.”

It is rare for fruits to be preserved in the fossil record.  However, seeds are more likely to survive the fossilisation process.  What palaeobotanists know about the evolution of angiosperms has been greatly enhanced by studying seeds and fossil pollen.  The earliest known grape seed fossils were found in India.  They are approximately sixty-six million years old.  At this time, there was a global extinction event.  This extinction was probably caused by the impact of an extra-terrestrial bolide.  This devastated life on Earth and led to a re-setting of ecosystems.  The composition of forests was altered as the extinction event affected both fauna and flora.

Fabiany Herrera in the field holding a grape fossil. Picture credit: Fabiany Herrera.

Picture credit: Fabiany Herrera

Dinosaur Extinction Helped Grape Growers

Herrera and his colleagues postulate that the extinction of the Dinosauria helped alter the flora within forests.

Co-author Mónica Carvalho explained:

“Large animals, such as dinosaurs, are known to alter their surrounding ecosystems. We think that if there were large dinosaurs roaming through the forest, they were likely knocking down trees, effectively maintaining forests more open than they are today.”

With the dinosaurs having died out and the absence of large mammals during the Palaeocene, forests became more crowded.  There were no large animals present to deplete the forest understorey and create a more open environment.  These new, dense forests provided an opportunity for plants like vines to become more widespread.  Ultimately, modern-day wine producers might have to thank dinosaurs for the evolution of the grape family of plants.

The diversification of mammals and birds may also have aided the spread of vines by helping to spread their seeds.

The Significance and Importance of Fossil Grapes

In 2013, Herrera’s PhD advisor and senior author of the new paper, Steven Manchester, published the paper describing the oldest known grape seed fossil from India.  Herrera suspected that ancient grape vines existed in South America too.

Herrera commented:

“Grapes have an extensive fossil record that starts about fifty million years ago.  I wanted to discover one in South America, but it was like looking for a needle in a haystack.  I’ve been looking for the oldest grape in the Western Hemisphere since I was an undergraduate student.”

Field work in the Colombian Andes with study co-author Mónica Carvalho provided the breakthrough.  Mónica discovered a fossilised grape seed.  The specimen was at least sixty million years old.  It was the first grape fossil to be found in South America.

Mónica Carvalho excitedly holding a grape fossil. Picture credit: Fabiany Herrera.

Picture credit: Fabiany Herrera

A Tiny Fossil Seed

The fossil seed is extremely small. However, Herrera and Carvalho were able to identify it based on its particular shape, size, and other morphological features. CT scans were undertaken to examine the fossil’s internal structure and confirm its affinity with the grape family.  This new taxon was named Lithouva susmanii.  The binomial name translates as “Susman’s stone grape”.  The name honours Arther T. Susman a supporter of South American palaeobotany at the Field Museum.

Co-author Gregory Stull of the National Museum of Natural History (Washington DC) explained the significance of these fossil grapes:

 “This new species is also important because it supports a South American origin of the group in which the common grape vine Vitis evolved.”

The field studies in Central and South America led to the scientific description of nine new species of fossil grapes.  These fossilised seeds not only tell the story of grapes’ spread across the Western Hemisphere, but also of the many extinctions and dispersals the grape family has undergone. The fossils are only distant relatives of the grapes native to the Western Hemisphere and a few, like the two species of Leea identified are only found in the Eastern Hemisphere today.

A Tumultuous Evolutionary Journey

These fossils suggest that the evolutionary journey of the grape family has been tumultuous.  Herrera commented that the fossil record of grapes demonstrates that these plants are extremely resilient.

Given the mass extinction our planet is currently facing, Herrera commented that studies like this one are valuable because they reveal patterns about how biodiversity crises play out.

Everything Dinosaur acknowledges the assistance of a media release from the Field Museum (Chicago) in the compilation of this article.

The scientific paper: “Cenozoic seeds of Vitaceae reveal a deep history of extinction and dispersal in the Neotropics” by Fabiany Herrera, Mónica R. Carvalho, Gregory W. Stull, Carlos Jaramillo and Steven R. Manchester published in Nature Plants.

The Everything Dinosaur website: Everything Dinosaur.

Ammonites were not in decline immediately before the End-Cretaceous extinction event that wiped out the dinosaurs.  Newly published research led by the University of Bristol has found that there is evidence to indicate that these cephalopods were still relatively successful at the end of the Age of Dinosaurs.  The study suggests the fate of ammonites was not set in stone.  Instead, the final few million years of their evolutionary history is more complex than previously thought.  Ammonite fossils might be very familiar, but we still have a lot to learn about the ammonoids.

Demonstrating a sequence of ammonite fossils identified from specific strata that helps to form a biostratigraphic column.  Ammonites provide an important resource to help with the relative dating of strata.  It was thought these marine molluscs were in decline in the Late Cretaceous, but new research challenges this theory.  Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Ammonite Fossils

Ammonites were marine molluscs that flourished in the Earth’s seas and oceans for more than 350 million years before they became extinct.  They died out during the same chance event that wiped out the dinosaurs, pterosaurs and most of the marine reptiles sixty-six million years ago.

It had been suggested that the extinction of the ammonites was inevitable as changes in climate and marine biota took hold.  It had been thought that the number of species was in decline at the end of the Cretaceous.

Newly published research challenges this assertion.  Writing in the journal “Nature Communications”, the scientists demonstrate that a detailed study of the ammonite fossil record reveals a more nuanced and complex picture.

Lead author of the study Dr Joseph Flannery-Sutherland (University of Bristol), stated:

“The fossil record tells us some of the story, but it is often an unreliable narrator. Patterns of diversity can just reflect patterns of sampling, essentially where and when we have found new fossil species, rather than actual biological history.  Analysing the existing Late Cretaceous ammonite fossil record as though it were the complete, global story is probably why previous researchers have thought they were in long-term ecological decline.”

The colourful heteromorphic ammonoid model – CollectA Pravitoceras.  An ammonite of the Late Cretaceous.

The picture (above) shows a model of an ammonite with an irregularly coiled shell (heteromorphic ammonite).  This is the CollectA Pravitoceras ammonite figure from the “CollectA Prehistoric Life” range.

To view the range of CollectA prehistoric animal models and figures in stock at Everything Dinosaur: CollectA Prehistoric Life Models and Figures.

A Database of Late Cretaceous Ammonite Fossils

In a bid to better understand Late Cretaceous ammonite speciation the researchers constructed a new database of Late Cretaceous ammonite fossils to help fill in the sampling gaps in their record.

Co-author of the study, Cameron Crossan, a 2023 graduate of the University of Bristol’s Palaeobiology MSc programme, explained:

“We drew on museum collections to provide new sources of specimens rather than just relying on what had already been published.  This way we could be sure that we were getting a more accurate picture of their biodiversity prior to their total extinction.”

Using this database, the researchers then analysed how ammonite speciation and extinction rates varied in different parts of the world. If ammonites were in decline through the Late Cretaceous, then their extinction rates would have been generally higher than their speciation rates wherever the team looked.  However, the team found that the balance of speciation and extinction changed both through geological time and between different geographic regions.

Two different types of ammonite (a regularly coiled homomorphic ammonite and an irregularly coiled heteromorphic ammonite) in a Late Cretaceous marine environment. Picture credit: Callum Pursall.

The differences in ammonoid diversification in different parts of the world has not been fully explored.  However, it is crucial to understanding their state prior to the mass extinction event.

Co-author Dr James Witts (London Natural History Museum), explained:

“These differences in ammonoid diversification around the world is a crucial part of why their Late Cretaceous story has been misunderstood.  Their fossil record in parts of North America is very well sampled, but if you looked at this alone then you might think that they were struggling, while they were actually flourishing in other regions.  Their extinction really was a chance event and not an inevitable outcome.”

Why Did Ammonoids Continue to be Successful?

To discover more about the factors responsible for the continued success of ammonoids, the team looked for possible influencing criteria that might have caused their diversity to change.  There are two contrasting theories.  Were speciation and extinction rates driven mainly by environmental conditions like sea temperatures and sea levels (the Court Jester Hypothesis), or by biological processes like pressure from predators and intraspecific competition (the Red Queen Hypothesis).

Co- author Dr Corinne Myers (University of New Mexico) commented:

“What we found was that the causes of ammonite speciation and extinction were as geographically varied as the rates themselves.  You couldn’t just look at their total fossil record and say that their diversity was driven entirely by changing temperature, for example. It was more complex than that and depended on where in the world they were living.”

Dr Flannery-Sutherland added:

“Palaeontologists are frequently fans of silver bullet narratives for what drove changes in a group’s fossil diversity, but our work shows that things are not always so straightforward. We can’t necessarily trust global fossil datasets and need to analyse them at regional scales. This way we can capture a much more nuanced picture of how diversity changed across space and through time, which also shows how variation in the balance of Red Queen versus Court Jester effects shaped these changes.”

Everything Dinosaur acknowledges the assistance of a media release from the University of Bristol in the compilation of this article.

The scientific paper: “Late Cretaceous ammonoids show that drivers of diversification are regionally heterogeneous” by Joseph Flannery-Sutherland, Cameron Crossan, Corinne Myers, Austin Hendy, Neil Landman and James Witts published in Nature Communications.

The Everything Dinosaur website: Prehistoric Animal Models and Toys.