Scientists have named and described a new species of herrerasaurian dinosaur from India.  The dinosaur which measured around three to four metres in length has been named Maleriraptor kuttyi. It fills a temporal gap between South American herrerasaurid dinosaurs and their younger relatives from North America. Herrerasaurs from South America are around nine million years older than herrerasaurs known from the Northern Hemisphere.  The discovery of M. kuttyi shows that herrerasaurs survived in Gondwana at least during the early Norian after the extinction event that led to the demise of the rhynchosaurs.

A skeletal drawing of the newly described herrerasaur from India Maleriraptor kuttyi. The shaded bones indicate known fossil material. Scale bar equals 1 metre. Picture credit: Royal Society Open Science (Maurício Silva Garcia).

Picture credit: Royal Society Open Science/Maurício Silva Garcia

Maleriraptor kuttyi

The fossilised remains of Maleriraptor kuttyi were collected more than four decades ago from the Upper Maleri Formation in Pranhita-Godavari Valley, less than half a mile south of the village of Annaram in south-central India.  It is known from fragmentary material. The fossil remains consist of the first sacral vertebra, part of the second sacral rib, a vertebra representing a caudosacral element or the first in the caudal series, a single anterior (close to the base of the tail) caudal vertebra. In addition, the right ilium, both ends of the right pubis, and part of the left pubis have been identified.

The genus name is derived from the Upper Maleri Formation, in which the holotype and only known specimen was collected, and the Greek word raptor, meaning thief, which is an ending commonly used for theropod genera. The species name commemorates the late T. S. Kutty, who discovered the holotype and co-authored its preliminary description with some of the authors of the recently published study.

Geographic and stratigraphic occurrence of Maleriraptor kuttyi. Palaeomap of the Late Triassic depicting the occurrences of the herrerasaurs (a). Overview of the Gondwana basins in India (b), with the Pranhita-Godavari valley highlighted and (c) detailed geological map of a portion of the Pranhita-Godavari valley indicating the type localities of the nominal dinosaur species of the Upper Maleri Formation. Picture credit: Royal Society Open Science.

Picture credit: Royal Society Open Science

Herrerasaurids Surviving into the Norian

The deposition of the Upper Maleri Formation probably occurred shortly after the extinction of rhynchosaurs, which are abundantly recorded in the Lower Maleri Formation, but completely unknown from the geologically younger Upper Maleri Formation.

Mike from Everything Dinosaur commented:

“Maleriraptor kuttyi demonstrates that herrerasaurs survived in Gondwana after the extinction event that wiped out the once abundant and geographically widespread herbivorous rhynchosaurs.”

The researchers conclude that this newly described Indian herrerasaur fills a temporal gap between the Carnian South American herrerasaurids and the younger middle Norian-Rhaetian herrerasaurs of North America.

The scientific paper: “A new herrerasaurian dinosaur from the Upper Triassic Upper Maleri Formation of south-central India” by Martín D Ezcurra, Maurício Silva Garcia, Fernando E Novas, Rodrigo Temp Müller, Federico L Agnolín and Sankar Chatterjee published by the Royal Society Open Science.

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Scientists writing in the academic journal “Cretaceous Research” have described theropod dinosaur remains from Lower Cretaceous deposits in Spain.  The fossils come from the province of Soria. They represent theropods excavated from the Western Cameros sub-basin.  Ironically, it is the eastern parts of the Cameros sub-basin that have yielded the majority of theropod remains.  In addition to mapping the Early Cretaceous theropod record, the researchers report evidence of a giant spinosaurid from this region.  Known as the Zorralbo I baryonychine, it is the largest Lower Cretaceous theropod described to date from Iberia.

The Zorralbo I baryonychine size estimate. Human figure provides the scale. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The Zorralbo I Baryonychine

In the Cameros Basin, theropods have been mostly documented in the Eastern Cameros sub-basin with baryonychine spinosaurids dominating the theropod biota. Theropods are much rarer in the Western Cameros sub-basin.  The authors describe fossils from the Western Cameros sub-basin, recovered in the upper Hauterivian–lower Barremian Golmayo Formation of the Soria province. Specifically, the theropod remains come from the Los Caños and Zorralbo I sites, which are located in the Las Camaretas and the Zorralbo areas, respectively, south-east of the main town of Golmayo.

The theropod record from the Iberian Peninsula is highly fragmentary.  However, in this paper, the authors identified the presence of three early-branching members of the Tetanurae along with three baryonychine dental morphotypes.  In addition, an enormous spinosaurid was identified.  Anatomical and phylogenetic study of the skull, post-cranial and appendicular (limb) bones suggest that this huge spinosaurid is also likely to be a baryonychine.

Whereas the Early Cretaceous theropod record is represented by carcharodontosaurians, coelurosaurians and tetanurans, it is the spinosaurids that are the most prominent.  Spinosaurs seem to be the dominant theropods of these Lower Cretaceous deposits.

Five Spinosauridae Genera

To date, five spinosaurid genera have been described from the Iberian Peninsula.  Although, there are many more genera likely to be present.

The five members of the Spinosauridae described so far:

• Iberospinus natarioi – to read our blog post about this theropod: A New Spinosaurus from Portugal.
• Protathlitis cinctorrensis – our blog post about this new dinosaur: Protathlitis – Member of the Spinosauridae Family.
• Riojavenatrix lacustris – named in 2024 (Isasmendi et al).
• Vallibonavenatrix cani – named in 2019 (Malafaia et al).
• Camarillasaurus cirugedae – named in 2014 (Sánchez-Hernández and Benton).

The Cameros Basin could provide an excellent analogue for the theropod biota of the Iberian Peninsula.

The scientific paper: “A giant spinosaurid from the Iberian Peninsula and new data on the Early Cretaceous Iberian non-avian theropod palaeodiversity” by Erik Isasmendi, Elena Cuesta, Adrián Páramo and Xabier Pereda-Suberbiola published in Cretaceous Research.

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

Researchers have described a new species of non-cerapodan neornithischian from the famous Upper Jurassic Morrison Formation of the western United States.  The dinosaur has been named Enigmacursor mollyborthwickae.  It is the most complete three-dimensionally preserved small ornithischian from the Morrison Formation known to date.  In addition, it is likely that there are numerous other small-bodied dinosaurs awaiting discovery.  The researchers, writing in the academic journal Royal Society Open Science conclude that small ornithischians are probably underrepresented.  Although the fossil record of these small dinosaurs is poor, Morrison Formation ornithischian species richness was likely higher than currently accepted.

A skeletal reconstruction (a) and (b) speculative life appearance of Enigmacursor mollyborthwickae. The shaded areas in the skeletal reconstruction represent known fossil material. Picture credit: Artwork by Bob Nicholls.

Picture credit: Artwork by Bob Nicholls (published in Royal Society Open Science)

Enigmacursor mollyborthwickae

The fossil material consists of a partial skeleton consisting of appendicular elements (limb bones), cervical, dorsal and caudal vertebrae, hip bones and three teeth. It was found on privately owned land (Moffat County, Colorado) and excavated by a commercial fossil collecting company. The fossil specimen now named NHMUK PV R 39000 was acquired by the London Natural History Museum in 2024.

The genus name is derived from “Enigma” which means puzzle or mystery. This is in reference to the convoluted taxonomic history of small-bodied ornithischian dinosaurs associated with the Morrison Formation. Furthermore, the genus name is derived from the Latin “cursor” for runner in recognition of the dinosaur’s elongated hind limbs and feet, adaptations for fast running. The species name honours Molly Borthwick. Her generous donation allowed the London Natural History Museum to purchase the specimen.

A Subadult Specimen

The Enigmacursor mollyborthwickae fossils probably represent a subadult.  Even when fully grown this dinosaur was tiny when compared to Morrison Formation giants such as Brontosaurus, Diplodocus, Apatosaurus and Stegosaurus.  It is thought that this dinosaur measured around 1.8 metres in length with a head height of approximately 65 centimetres.  Its tail was probably longer than the rest of its body.

The elongated feet (pedes) of the newly described (2025) non-cerapodan neornithischian E. mollyborthwickae. The feet and long hind limbs indicate that this small dinosaur was a fast runner. Picture credit: Royal Society Open Science.

Picture credit: Royal Society Open Science

The picture (above) shows the reconstructed feet (pedes) of Enigmacursor.  The right foot (pes) is represented in images a to c, whereas the left pes is shown in images d to f.

Key

Pedes of specimen number NHMUK PV R 39000, Enigmacursor mollyborthwickae, in (a–c) right pes; (d–f) left pes.  Proximal views (a and d).  Anterior/flexor views (b and e).  Posterior/plantar views (c and f).  Note that MT equals metatarsal and that the greyed-out areas indicate reconstruction.  Scale bars for b, c, e and f equal five cm. In contrast, the scale bars for images a and d are two cm.

Living Alongside Giants

Although the remains of small, cursorial ornithischian dinosaurs from the Morrison Formation have been known about for over 150 years, most of the 19th and early 20th century specimens are poorly preserved and incomplete. These dinosaurs have tended to be overlooked as palaeontologists focused on the larger taxa present. Many of these small ornithischians are designated nomina dubia. This means that any scientific name applied is doubtful and likely to be invalid.

Small dinosaurs from the Upper Jurassic Morrison Formation are not the only extinct animals to suffer from this form of bias. When modern ecosystems are studied, it is very notable that living alongside the megafauna there is a whole array of smaller animals.  It is likely that ecosystems in the Mesozoic were similar with many more types of small dinosaur (under one hundred kilograms), living amongst much larger animals.

To read a related article about a small, almost overlooked pachycephalosaur: A New Bone-headed Dinosaur is Scientifically Described.

Fortunately, the fossils of Enigmacursor will have the opportunity to take centre stage.  This little dinosaur is part of a new exhibit at the London Natural History Museum.  This is the first new fossil dinosaur exhibit at the Museum for eleven years.  Ironically, the last new dinosaur exhibit at the Museum was a contemporary of E. mollyborthwickae.  In 2014, the London Natural History Museum opened a new exhibit featuring a Stegosaurus.

Right lateral View of “Sophie” the Stegosaurus (London Natural History Museum). Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Everything Dinosaur acknowledges the assistance of the Royal Society open access paper in the compilation of this article.

The scientific paper: “Enigmacursor mollyborthwickae, a neornithischian dinosaur from the Upper Jurassic Morrison Formation of the western USA” by Susannah C. R. Maidment and Paul M. Barrett published by Royal Society Open Science.

The award-winning Everything Dinosaur website: Dinosaur and Prehistoric Animal Models.

It is the end of this year’s excavation season for Bromacker project team members. The excavations at the world-famous Bromacker fossil site in Thuringia (Germany) have been a success. A layer of fossils bones, small skeletons and an ash layer suitable for age determination promise new insights into the 290-million-year-old ecosystem of the Bromacker locality.  In just eighteen days, over fourteen hundred volunteers participated in the field work. Congratulations to everyone involved in this exciting project.

Field team members working on the Bromacker project (June 2025). Picture credit: Bromacker Projektteam.

Picture credit: Bromacker Projektteam

A Successful Conclusion to this Year’s Bromacker Project Field Work

The Bromacker location is one of the world’s most significant fossil sites documenting an Early Permian terrestrial ecosystem. An international research team consisting of palaeontology and geology experts, including students, technical staff and science communicators, has been excavating at the Bromacker locality for several weeks every year since 2020. The Museum für Naturkunde Berlin, the Friedrich Schiller University Jena, the Friedenstein Foundation Gotha, and the UNESCO Global Geopark Thuringia Inselsberg – Drei Gleichen are involved in the project.

To read an earlier blog post about the discovery of fossilised skin impressions at the site: Early Synapsids and Skin Impressions.

Approximately fifty researchers from six countries took part in this year’s excavation work. Over two hundred and fifty fossils were recovered from the site.

Project and excavation manager Prof Jörg Fröbisch (Museum für Naturkunde Berlin) is extremely pleased with the new finds.

He commented:

“This year’s excavation at Bromacker was once again a huge success and has revealed completely new aspects. This again includes numerous and varied finds of prehistoric bones, trace fossils, invertebrates and plants. The discovery of an extensive bone layer and two small skeletons, possibly from early reptiles, is particularly exciting. We have also examined one of the massive sandstone beds for the first time and discovered vertebrate burrow systems and plant remains. The identification of an ash layer is also spectacular, which we hope will allow us to determine the exact age of the find layers for the first time.”

The Free State of Thuringia is continuing the funding until the middle of 2026. With the continuation of excavations, preparation, collection management and various educational programmes and communication formats for the general public, the future of the UNESCO World Heritage status of the Thuringia Inselsberg – Drei Gleichen Geopark is secured.

Dr Tom Hübner (Friedenstein Foundation Gotha), is delighted with this news.

Dr Hübner added:

“The new commitment of the state of Thuringia to the Bromacker is of particular significance and underlines the importance of this unique fossil site for the region and far beyond. We are particularly pleased that the recently approved funding will make it possible to carry out another excavation next year.”

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

Visit the Everything Dinosaur website: Dinosaur Toys and Models.

A new species of tyrannosauroid described by scientists as a “missing link” sheds new light on the evolution of Late Cretaceous tyrannosaurs.  The dinosaur, named Khankhuuluu mongoliensis represents a transitional form between the small, gracile early tyrannosauroids and the giant, bone-crushing, apex predators such as Daspletosaurus and Tyrannosaurus rex.  The large tyrannosaurs from the end of the Cretaceous (Campanian and Maastrichtian) have been intensively studied.  However, the evolutionary origins of these super-sized theropods remains poorly understood.  It is known that these dinosaurs evolved from much smaller ancestors.  The discovery of Khankhuuluu (pronounced: khan-KOO-loo), helps palaeontologists to fill in a gap between these ancestral forms and the Late Cretaceous giants.

Khankhuuluu mongoliensis represents a transitional form between small tyrannosauroids of the early Late Cretaceous and the giants of Campanian and Maastrichtian. Yes, I know Maastrichtian is not correct in the diagram :). Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Khankhuuluu mongoliensis

A team of researchers led by scientists from the University of Calgary (Alberta) have described a new species of tyrannosauroid from the Upper Cretaceous Bayanshiree Formation of southeastern Mongolia. University of Calgary PhD student Jared Voris found unique autapomorphies in two fossil specimens that had been assigned to the tyrannosauroid Alectrosaurus. For example, an air cavity was identified in the nasal bone and the student found other traits that indicate this dinosaur was evolving the skull anatomy that would generate immense bite forces.

Phylogenetic analysis suggests that K. mongoliensis sits just outside the Eutyrannosauria. This is the clade which contains giant tyrannosaurs such as Gorgosaurus, Lythronax, Tarbosaurus and T. rex as well as, smaller more lightly built predators.

The Eutyrannosauria is split into two tribes:

• Alioramini (for example Qianzhousaurus and Alioramus): smaller, slender, shallow-skulled forms.
• Tyrannosaurini (for example Tyrannosaurus rex): massive, deep-skulled forms.

Khankhuuluu and the Alioramini both share certain traits. They are lightly built, have long hind limbs and shallow skulls.  These characteristics are seen in juvenile specimens of the giant tyrannosaurs such as Tarbosaurus and T. rex. These traits evolved due to heterochrony, meaning changes in the timing of growth during evolution.  Writing in the journal “Nature” the research team which included Professor Darla Zelenitsky (University of Calgary) suggest that accelerated growth led to the evolution of the giant forms of tyrannosaur (peramorphosis). In contrast, the Alioramini retained juvenile traits into adulthood (paedomorphosis).  This explains, their smaller size and gracile build.

It is postulated that the different body types of the Alioramini and Tyrannosaurini likely helped them live side by side in Asia by filling different ecological roles.

The Prince of Dragons

The fossils were discovered in the 1970s at the Baishin-Tsav locality (Bayanshiree Formation). The strata are believed to have been laid down in the Turonian to Santonian faunal stages of the Late Cretaceous. The fossils of Khankhuuluu mongoliensis are thought to be approximately 86 million years old. Khankhuuluu is estimated to have weighed around 750 kilograms and measured around four metres in length.

The dinosaur’s name translates as “Mongolia’s Prince of Dragons”.  It hints that this theropod was a prince that led to the evolution of the “tyrant kings”.

The Everything Dinosaur blog has documented numerous articles about new discoveries leading to the erection of new Tyrannosauroidea taxa.  Most of these dinosaurs were considerably smaller than Khankhuuluu.

To read about the discovery of a small-bodied tyrannosauroid from southern Laramidia: Suskityrannus – The Shape of Things to Come.

The contemporary Timurlengia from Uzbekistan: New Dinosaur Sheds Light on How Tyrannosaurs Got Big.

Moros intrepidus, a member of the Superfamily Tyrannosauroidea from Utah: Moros – A Diminutive Tyrannosauroid.

Alioramini Not a Basal Lineage

Previously, phylogenetic analysis had relied too much on immature specimens, and this led to the assumption that the Alioramini were a primitive, early diverging group. However, the researchers postulate that the Alioramini were not basal, but more derived representing theropods that retained immature features into adulthood.

Furthermore, the study reveals that Asian tyrannosauroids (similar to Khankhuuluu) dispersed to North America. They gave rise to the Eutyrannosauria. The Eutyrannosauria diversified and remained exclusively in North America until a single dispersal to Asia in the latest Cretaceous that established the Alioramini and Tyrannosaurini tribes.

The scientific paper: “A new Mongolian tyrannosauroid and the evolution of Eutyrannosauria” by Jared T. Voris, Darla K. Zelenitsky, Yoshitsugu Kobayashi, Sean P. Modesto, François Therrien, Hiroki Tsutsumi, Tsogtbaatar Chinzorig and Khishigjav Tsogtbaatar published in Nature.

The Everything Dinosaur website: Dinosaur Models and Toys.

Scientists have revealed the last meal of an Australian herbivorous dinosaur that lived ninety-five million years ago.  Researchers writing in the journal “Current Biology” report on the discovery of Diamantinasaurus matildae stomach contents.  This remarkable discovery is the first time that sauropod stomach contents have been identified.  The analysis of the plant remains suggests bulk feeding and multi-level browsing.  The Diamantinasaurus nicknamed “Judy” was not fussy when it came to food.  Plants eaten by Diamantinasaurus include conifers, seed ferns and angiosperms. In addition to the fossilised stomach contents, the scientists also examined mineralised skin found with the specimen. This revealed a pattern of polygonal (often hexagonal) non-overlapping scales, a characteristic commonly seen in other sauropods.

A life reconstruction of the Australian titanosaur Diamantinasaurus matildae. Picture credit: Travis Tischler.

Picture credit: Travis Tischler

Diamantinasaurus matildae Stomach Contents

Sauropods were abundant and diverse throughout the Jurassic and Cretaceous.  The Sauropoda include the largest terrestrial animals known to science.  Studies of teeth suggest these dinosaurs were herbivorous.  However, our knowledge of their diet is based on indirect evidence such as coprolites (dung).  Furthermore, no fossilised gut contents (cololites) were known.  Intriguingly, this all changes with the publication of a remarkable study that describes Diamantinasaurus matildae stomach contents.

Subadult Diamantinasaurus matildae stomach contents. Undigested leaves can be clearly observed in the cololite. Picture credit: Australian Age of Dinosaurs.

Picture credit: Australian Age of Dinosaurs

The fossil material was collected from Winton Formation exposures (Queensland, Australia).  The cololite was located in the abdominal region and closely associated with a layer of mineralised skin.  Detailed analysis of the cololite reveals the plant material eaten.  Conifer pinnules, angiosperm leaves, and seed-fern fruiting bodies are preserved.  In addition, chemical biomarkers are identified consistent with angiosperms and gymnosperms.

This Diamantinasaurus matildae cololite provides the first direct, empirical evidence in sauropods of herbivory, demonstrating generalist feeding, low- to high-level browsing, and minimal oral processing of food.  It seems that these animals were not fussy what plant material they consumed.  They did not chew or grind up their food, relying on their enormous guts to digest the plant material.  Food may have persisted in their guts for a fortnight or more before being excreted.

Australian Age of Dinosaurs Collection Manager Mackenzie Enchelmaier (co-author of the study) highlighting the Diamantinasaurus gut contents. Picture credit: Australian Age of Dinosaurs.

Picture credit: Australian Age of Dinosaurs

The study marks the first use of molecular techniques to identify sauropod stomach contents.

Sauropods Feeding at a Range of Heights

The research was led by Dr Stephen Poropat (Curtin University, Perth, Western Australia).  The Diamantinasaurus specimen, originally found in 2017 has provided unprecedented detail on the feeding habits and diets of the Sauropoda.

The first direct, empirical evidence in sauropods of herbivory, demonstrating generalist feeding, low- to high-level browsing, and minimal oral processing of food. Picture credit: Australian Age of Dinosaurs.

Picture credit: Australian Age of Dinosaurs

To read Everything Dinosaur’s blog post from 2009 about the discovery of Diamantinasaurus: A Trio of New Dinosaurs from Australia.

Dr Poropat stated:

“The specific plants that they ate, and the height above ground at which they fed, have remained unknown – until now. The stomach contents we found belonged to a 12-metre-long, subadult sauropod that was still growing at the time of its death. Our findings show that at least some species of subadult sauropods were able to feed at a range of heights above ground level, and consequently were equipped to deal with environmental and vegetation changes throughout the Jurassic and Cretaceous periods.”

Co-author of the study, John Curtin Distinguished Professor Kliti Grice added:

“By using advanced organic geochemical techniques, we were able to confirm the presence of both angiosperms and gymnosperms in the diet of this sauropod. This unique approach provided molecular evidence of the plants that sauropods consumed.”

Mineralised Skin

Furthermore, this amazing titanosaur fossil specimen revealed details of its skin texture. The researchers identified a pattern of five-sided (often hexagonal), non-overlapping scales. This type of integumentary covering has been found in other sauropod specimens. The scales measure between seven and thirteen mm in diameter.   Each scale is covered in small bumps (papillae).  Their appearance is consistent with other known sauropod skin fossils.

Mineralised skin found with the Diamantinasaurus specimen known as Judy reveals polygonal (often hexagonal) scales. Picture credit: Australian Age of Dinosaurs.

Picture credit: Australian Age of Dinosaurs

The Diamantinasaurus matildae stomach contents and mineralised skin were preserved alongside yet-to-be-published body fossils of the subadult.  The fossils are housed at the Australian Age of Dinosaurs Museum. These fossils will form a key part of the Australia Through Time exhibition in the Museum’s future multi-million-dollar facility.

The longevity of the clade Sauropoda was underpinned by the persistence through time of generalist feeders like Diamantinasaurus matildae that were capable of feeding at a range of heights on a wide variety of different plant species.

Everything Dinosaur acknowledges the assistance of a media release from the Australian Age of Dinosaurs in the compilation of this article.

The scientific paper: “Fossilized gut contents elucidate the feeding habits of sauropod dinosaurs” by Stephen F. Poropat, Anne-Marie P. Tosolini, Samantha L. Beeston, Mackenzie J. Enchelmaier, Adele H. Pentland, Philip D. Mannion, Paul Upchurch, Karen Chin, Vera A. Korasidis, Phil R. Bell, Nathan J. Enriquez, Alex I. Holman, Luke M. Brosnan, Amy L. Elson, Madison Tripp, Alan G. Scarlett, Belinda Gode, Robert H. C. Madden, William D. A. Rickard, Joseph J. Bevitt, Travis R. Tischler, Tayla L. M. Croxford, Trish Sloan, David A. Elliott and Kliti Grice published in Current Biology.

For models and replicas of dinosaurs and other prehistoric animals: Dinosaur Models.

A newly published paper postulates that ungulate evolution has been shaped by two major ecological shifts. Tectonic shifts and global climate change have been the drivers of major biota turnover amongst large herbivorous mammals.

Ungulates are hoofed mammals.  This extremely diverse clade is subdivided into two orders, the Artiodactyla (even-toed) mammals that walk on two of their five toes and the Perissodactyla (odd-toed) mammals that walk on one or three toes. Molecular data led to a reclassification at the turn of the century with the establishment of a larger clade the Euungulata.

• Typical artiodactyls – ruminants such as cattle, goats, sheep, llamas, camels, hippos, giraffes, deer, pigs.
• Typical perissodactyls – rhinos, horses, tapirs.

It should be noted that the odd-toed ungulates were much more diverse in the past.  Brontotheres and knuckle-walking chalicotheres are extinct members of the Perissodactyla.

A wonderful prehistoric animal model. A 1:20 scale replica of the chalicothere Moropus – an extinct perissodactyl.

The picture above shows a typical chalicothere.  It is a 1:20 scale replica of Moropus from CollectA.  To view the range of CollectA scale prehistoric animal models: CollectA Deluxe Prehistoric Life.

Large Herbivores Shaping the Landscape

Large herbivores have shaped the Earth’s landscapes for the last forty million years.  A new study led by researchers from the University of Gothenburg in collaboration with scientists from Spain and the Museum für Naturkunde Berlin examines how these animals reacted to dramatic environmental changes.  The study, published in “Nature Communications” demonstrates that ecosystems managed to remain stable despite the extinction of many families.

Ungulates and other large mammals such as elephants are key ecosystem engineers.  The decline of large herbivores threatens entire habitats.  These large herbivores shape landscapes and promote biodiversity.  Current extinction rates, often referred to as the sixth mass extinction could lead to a loss of key taxa.

Dr Fernando Blanco, a visiting scientist at the Museum für Naturkunde Berlin led the research.  The fossils of over three thousand large herbivores from the past sixty million years to more recent times were studied.

Dr Blanco commented:

“We found that these ecosystems have remained surprisingly stable over long periods of time, even though species were added and others became extinct. Twice in the last sixty million years, however, the environmental pressure was so great that the entire system was globally reorganised.”

The End of the Tethys

The team discovered that the first major reorganisation of ecosystems took place around twenty-one million years ago.  This was during the Miocene Epoch.  The Tethys Sea closed and this created a landbridge between Eurasia and Africa.  A mass migration of species occurred. The ancestors of many extant ungulates moved into new habitats.  This had a profound effect on ungulate evolution.

A second major reorganisation of ecosystems occurred approximately ten million years ago.  This was during the Tortonian stage of the Miocene. Global cooling led to a massive reduction in forests and the spread of grasslands.  This led to a dramatic increase in grazing species and a gradual disappearance of many forest-dwelling species.  The researchers postulate that this was the beginning of a sustained decline in the functional diversity of large, herbivorous mammals.  This has led to a decrease in their influence over the planet’s ecosystems. Despite the extinctions, the researchers found that the basic ecological structure of herbivore communities remained remarkably stable.  Ecosystems remained stable even when many iconic taxa died out such as mastodons, mammoths and giant rhinoceroses.

A typical artiodactyl – a Cape buffalo (Syncerus caffer) photographed in Tanzania. Scientists reflect on ungulate evolution and the impact of large herbivores on the Earth’s ecosystems. Picture credit: Juan López Cantalapiedra.

Picture credit: Juan López Cantalapiedra

Co-author of the study, Dr Ignacio A. Lazagabaster from CENIEH (Centro National de Investigacion Sobre la Evolucion Humana, Spain) commented:

“It’s like a football team changing players during a game without the line-up changing significantly. New species came into play and the communities changed, but the new players fulfilled similar ecological tasks – as a result, the overall structure remained stable.”

The Resilience of Large Herbivores is Not Guaranteed

The research team remarks on the resilience of large mammals to survive glaciation, global cooling and other environmental crises.  However, many large taxa are extremely vulnerable today.

Fellow co-author of the study Dr Juan L. Cantalapiedra from the Spanish MNCN (Museo Nacional de Ciencias Naturales) stated:

“Our results show how enormously adaptable ecosystems can be. But there are limits. If we continue to lose species and their ecological roles on such a massive scale as in the present, we could soon reach a third global tipping point – and we humans are actively contributing to this.”

Everything Dinosaur acknowledges the assistance of the Museum für Naturkunde Berlin in the compilation of this article.

The scientific paper: “Two major ecological shifts shaped 60 million years of ungulate faunal evolution” by Fernando Blanco, Ignacio A. Lazagabaster, Óscar Sanisidro, Faysal Bibi, Nicola S. Heckeberg, María Ríos, Bastien Mennecart, María Teresa Alberdi, Jose Luis Prado, Juha Saarinen, Daniele Silvestro, Johannes Müller, Joaquín Calatayud and Juan L. Cantalapiedra published in Nature Communications.

For models of extinct mammals and other prehistoric animals: Prehistoric Animal Models and Toys.

Researchers have discovered the earliest evidence known to science of birds nesting in the Arctic.  A newly published study in the journal “Science” indicates that birds were nesting in polar regions during the Late Cretaceous.  Ancient Arctic birds nested alongside dinosaurs.  Fossils collected from the famous Prince Creek Formation of Alaska push back the record of Arctic nesting birds by up to thirty million years.

An illustration of Cretaceous Period birds with other dinosaurs from the same time period in the background. A paper in the journal Science documents the earliest-known example of birds nesting in the polar regions. A dromaeosaur feeds whilst Pachyrhinosaurus congregate in the background. Picture credit: Gabriel Ugueto.

Picture credit: Gabriel Ugueto

Ancient Arctic Birds

The University of Alaska Fairbanks led the research team.  However, researchers from the University of Reading were involved.  The scientists identified dozens of tiny fossil bones and teeth from the Alaskan excavation site.  Multiple types of birds were breeding in the Arctic. For example, diving birds that resembled loons, gull-like birds, and several kinds of birds similar to modern ducks and geese.  Analysis of the structure of the fossil material demonstrated that the bones represented very young birds such as hatchlings.

A hatchling bird beak, top left, and three foot bones are pictured to scale on a penny. The bones’ spongy texture tells scientists that they come from hatchlings, rather than adult birds. Picture credit: Pat Druckenmiller.

Picture credit: Pat Druckenmiller

The sediments are approximately seventy-three million years old (late Campanian faunal stage of the Cretaceous).

To read a blog post about dinosaurs nesting in the Arctic: Dinosaurs Nested in the Arctic.

Lead author of the study, Lauren Wilson, a doctoral student at Princeton University commented:

“Birds have existed for 150 million years. For half of the time they have existed, they have been nesting in the Arctic. Finding bird bones from the Cretaceous is already very rare. To find baby bird bones is almost unheard of. That is why these fossils are significant.”

More than Fifty Bird Fossils Found

Birds are key components in modern polar ecosystems.  Many species breed in these regions and spend all year either in the Arctic or Antarctic.  Although the Cretaceous polar regions were much warmer than today, they were still extreme, harsh environments.  Cretaceous polar regions would have experienced months of near total darkness.  They were challenging environments to colonise even though they were not as cold as they are today.  The fossil assemblage from the Prince Creek Formation suggests that chicks and adults of multiple species lived in the Arctic.  This suggests that birds began breeding in the Arctic early on in their evolution.

Prior to this research, the earliest known evidence of birds breeding in the polar regions dates to approximately forty-seven million years ago.  This was during the Eocene Epoch. The fossil material used in this study was collected from Prince Creek Formation exposures along the Colville River. Rather than focusing on large bones, the scientists collected every bone and tooth they could find from screen washes. Screen washing involves taking tubs of sediment and screening the sediments using sieves.  Once the majority of the stones and pebbles have been removed the remaining material is examined under a microscope.  In this way, tiny fossils including those of hatchling birds can be identified.

Joe Keeney, Patrick Druckenmiller and Jim Baichtal excavate at a site on the Colville River. Picture credit: Lauren Wilson.

Picture credit: Lauren Wilson

Evidence of Neornithes

Some of the tiny bones have skeletal features only found in Neornithes, the group that includes all extant birds. Like extant birds, some of these ancient species had no true teeth.

Co-author of the study, Dr Jacob Gardner (University of Reading) commented:

“Determining the identity of fossils using separate individual bones is notoriously difficult. For the first time, we determined the identities of large numbers of fossils using high-resolution scans and the latest computer tools, revealing an enormous diversity of birds in this ancient Arctic ecosystem. Polar bird communities have deeper evolutionary roots than previously imagined.”

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

The scientific paper: “Arctic bird nesting traces back to the Cretaceous” by Wilson, L. N., Ksepka, D. T., Wilson, J. P., Gardner, J. D., Erickson, G. M., Brinkman, D., Brown, C. M., Eberle, J. J., Organ, C. L. and Druckenmiller, P. S. published in the journal Science.

For models and replicas of prehistoric animals: Dinosaur and Prehistoric Animal Models.

Newly published research suggests that Allosaurus europaeus is not a valid taxon. A detailed study of Portuguese fossil material has led to the conclusion that the A. europaeus holotype (ML 415) represents Allosaurus fragilis.

The remains of large theropods ascribed to the Allosaurus genus have been found in Portugal. In 1988, fossils of a meat-eating dinosaur were discovered near the village of Andrés, (Leiria District, Portugal). Additional fossil finds from the coast at Praia de Vale Frades, (Lourinhã, Portugal) and a coal mine in the district of Leiria were assigned to Allosaurus. Subsequently, a European Allosaurus was erected in 2006 (Mateus et al). This dinosaur was named Allosaurus europaeus.  However, a detailed analysis of cranial material has led researchers to conclude that fossils attributed to A. europaeus should be bracketed as Allosaurus fragilis.

A life-size replica of an Allosaurus. The genus was first erected in 1877 (Marsh). Several species have been named but the validity of many of these species has been challenged. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The Demise of Allosaurus europaeus

Allosaurus fragilis was first described in the Upper Jurassic of Portugal in 1999 based on a set of postcranial remains collected at the Andrés fossil site in Pombal. The description of a second species, Allosaurus europaeus, based on elements from the back of the skull and a sequence of tail bones (ML 415) collected at Praia de Vale Frades in Lourinhã was controversial.  The scientists provide a detailed description of a new sample of skull fossil material.  These fossils from the village of Andrés are confidentially assigned to the Allosaurus genus.

In addition to the fossil study a comprehensive phylogenetic assessment of the Morrison Formation fossil record of Allosaurus was performed. The phylogenetic analysis indicates that there were only two valid Allosaurus species present in the Late Jurassic ecosystems of North America.  These species are Allosaurus fragilis and the recently erected Allosaurus jimmadseni.

To read Everything Dinosaur’s blog post about the establishment of A. jimmadseni as a separate species: A New Species of Allosaurus.

Manufacturers of prehistoric animal models were quick to introduce replicas of this new Allosaurus species.  Allosaurus jimmadseni was erected in 2020.  The American company Creative Beast Studios introduced an articulated replica of A. jimmadseni.

This figure has proved popular with collectors, especially collectors based in the USA.

To view the range of Beasts of the Mesozoic/Cenozoic figures: Beasts of the Mesozoic Figures.

The new Beasts of the Mesozoic Cyberzoic figure (A. jimmadseni) is one of the highlights of the latest customer newsletter. Shortly, after this new species was erected, new Allosaurus models came onto the market. Picture credit: Everything Dinosaur.

Referring Specimens to Allosaurus fragilis

The authors of the paper postulate that their analysis indicates that only two valid Allosaurus species were present in the Late Jurassic ecosystems of North America.  These two species are Allosaurus fragilis and Allosaurus jimmadseni.  The researchers provide an updated reference for Allosaurus classification.  The Portuguese specimens MNHN/UL.AND.#, ML 415, and MG 27804 are interpreted as belonging to A. fragilis.

This new research helps palaeontologists to better understand the evolution of theropods associated with the Lusitanian Basin.  The researchers consider that this study provides evidence of a close biogeographical relationship between North America and Europe during the Late Jurassic.

The scientific paper: “Cranial osteology of a new specimen of Allosaurus Marsh, 1877 (Theropoda: Allosauridae) from the Upper Jurassic of Portugal and a specimen-level phylogenetic analysis of Allosaurus” by Elisabete Malafaia, Pedro Dantas, Fernando Escaso, Pedro Mocho and Francisco Ortega published in the Zoological Journal of the Linnean Society.

The Everything Dinosaur website: Dinosaur Models.

Researchers have identified fossil tracks with skin impressions of early synapsids from the famous Bromacker fossil site in Thuringia (Germany).  These are the oldest skin impressions of early mammalian relatives known.  They provide unique insights into the evolution of scales and integumentary coverings within an Early Permian ecosystem.  The Bromacker quarry exposes 290-million-year-old deposits associated with the Tambach Formation. This rare site preserves exquisite, articulated fossils of a unique vertebrate fauna.  This quarry has been at the centre of a long research project, lasting decades led by the Museum für Naturkunde Berlin.

290-million-year-old skin impression fossils. Picture credit: Lorenzo Marchetti.

Picture credit: Lorenzo Marchetti

Studying the Trace Fossils of Early Synapsids

The fossil tracks were discovered over a century ago. These rare fossils were re-examined as part of the ongoing Bromacker research project.  This research project is run by the Federal Ministry of Research, Technology and Space.  The scientific paper has been published in the journal “Current Biology”.

Senior author of the study, Professor Jörg Fröbisch commented:

“It has been shown time and again that certain characteristics and traits of modern vertebrates, such as skin structure, lifestyle or social behaviour, appeared earlier in the course of evolutionary history than was initially assumed. The study once again demonstrates the globally unique significance of the fossil deposit at Bromacker and its enormous potential for future research.”

To read a blog post about a Dimetrodon fossil found at the Bromacker locality: Fossil Mystery is Solved.

Scales on the Underside, Legs and the Tail

One trackway preserved at the site is particularly illuminating. An impression preserved in the fine-grained Tambach sandstone reveals skin folds on the toes and various types of scales on the upper and lower legs.  There are also scale impressions from the ventral portion of the tail, the hip area and the abdomen.  The scientists have identified this as a resting track or evidence of a Permian vertebrate wallowing.

The arrangement and shape of the scale marks, sometimes diamond-shaped, rectangular, pentagonal to polygonal, sometimes overlapping like roof tiles, is reminiscent of the horny scales of membranous reptiles.

Evidence of Social Behaviour in Early Synapsids

A number of sandstone slabs preserve large numbers of tracks.  Several tracks are adjacent to each other, and some tracks are parallel.  The researchers suggest this is evidence of animals of the same species walking together.  The track producers, early synapsids such as Dimetrodon teutonis, probably rested, basked and cooled down together.  This suggests that these Permian animals demonstrated group behaviours, just like modern lizards, birds and mammals.

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

The scientific paper: “Early Permian synapsid impressions illuminate the origin of epidermal scales and aggregation behaviour” by Marchetti, L., Logghe, A., Buchwitz, M., and Fröbisch, J. published in Current Biology.

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