New Study Reveals Surprising Abundance of Ceratopsians in Europe’s Cretaceous Fauna

Paleontologists have made significant strides in understanding Europe’s elusive ceratopsians through newly discovered fossils and advanced imaging techniques. Notably, the iguanodon has been reclassified as a true member of the ceratopsian clade.



Possible restoration of Aikaceratops kosmai. Image credit: Matthew Dempsey.

Ceratopsians are a fascinating group of herbivorous ornithischian dinosaurs recognized for their unique parrot-like beaks, bony frills, and distinctive horns.

These remarkable creatures thrived primarily during the Late Cretaceous period, approximately 100 to 66 million years ago.

While ceratopsian fossils are plentiful in Asia and North America, they are notably scarce in Europe.

Previously, evidence in Europe consisted of only a few incomplete and contentious specimens.

The recent discovery of new, well-preserved fossils of Aikaceratops from the Late Cretaceous in Hungary has sparked new research employing CT scans and thorough evolutionary analysis.

Initially described in 2010, Aikaceratops has faced controversy, with some experts regarding it as a horned dinosaur and others viewing it as a distant relative of the ceratopsians, particularly the iguanodon. Despite the debate, it exhibits traits that suggest ceratopsian characteristics.

Utilizing new skull material, Professor Susannah Maidment from the Natural History Museum and the University of Birmingham, along with her colleagues, determined that the dinosaur is not only a ceratopsian but also part of the previously identified rhabdodontid family, which includes Moclodon.

The analysis revealed that several previously misclassified dinosaurs assumed to be rhabdodontids were in fact ceratopsians.

“Although iguanodon and triceratops appear distinctly different, they share a common ancestor, inheriting certain traits,” Professor Maidment stated.

“Both groups uniquely evolved four legs, complex chewing mechanisms, and large body sizes.”

“This shared history makes their teeth and limbs quite similar, complicating classification based on partial skeletons.”

This study confirms the presence of ceratopsians in Europe, addressing a long-standing gap in our understanding of these dinosaurs’ migration across the Northern Hemisphere.

“The initial fossil of Aikaceratops was so incomplete that many scientists doubted its classification as a ceratopsian,” noted Professor Richard Butler from the University of Birmingham.

“What’s fascinating about the new findings regarding Aikaceratops is that they validate the existence of horned dinosaurs in Cretaceous Europe and challenge us to rethink our understanding of ancient ecosystems.”

The earliest ceratopsians, such as Yinlong, originated in Asia and migrated multiple times to North America, leading to the evolution of frilled species like triceratops and Torosaurus.

The most plausible route for this dispersal would have been through Europe, though the scarcity of fossils has posed challenges.

“We know that dinosaurs were capable of crossing the Atlantic Ocean, which was just starting to form during the Cretaceous,” explained Professor Maidment.

“Dinosaurs like Allosaurus have been discovered in both Portugal and the United States, suggesting some level of intercontinental travel was possible.”

“Many dinosaurs could swim, and the islands within the Central European Basin were relatively close, making island-hopping a likely scenario.”

“While triceratops is one of the most recognized horned dinosaurs, most species are native to North America, and many were once misidentified as other types, leading to their obscured presence in Europe,” remarked Professor Steve Brusatte from the University of Edinburgh.

The findings are detailed in a study published in the journal Nature.

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SCR Maidment et al. Hidden diversity of ceratopsians in Late Cretaceous Europe. Nature published online on January 7, 2026. doi: 10.1038/s41586-025-09897-w

Source: www.sci.news

Coexistence of Two Coelurosaur Species in Cretaceous Brazil.

Paleontologists have undertaken a thorough anatomical reevaluation of the fossilized remains of two coelurosaurian theropod dinosaurs that inhabited South America during the Early Cretaceous period: Santanaraptor Placidus and Milischia asymmetrica.

Hypothetical reconstruction of Milischia asymmetrica (left) and Santanaraptor Placidus (right), focusing on lizards that existed in what is now northeastern Brazil approximately 112 million years ago. Image credit: Guilherme Gehr.

Santanaraptor Placidus and Milischia asymmetrica thrived in Brazil during the Early Cretaceous period, roughly 112 million years ago.

The holotypes of these coelurosaurs were discovered in Romualdo Formation in 1996 and 2000, respectively.

Dr. Rafael Delcourt from the University of São Paulo and his team stated, “The Romualdo Formation is a renowned Early Cretaceous fossil hotspot situated along the edge of the Araripe Plateau in northwestern Brazil.”

“Its megafossil record encompasses plants, invertebrates, turtles, crocodiles, pterosaurs, theropod dinosaurs, as well as one of the most diverse and well-preserved ichthyofaunas from the Mesozoic era.”

“Spinosaurids are among the most notable Romualdian theropods, with numerous reference specimens including the well-preserved skull of Illitator Challenger and the snout of Illitator Challenger Angaturama Limai.”

“Both Santanaraptor Placidus and Milischia asymmetrica originate from the same deposits that produced Spinosaurus, specifically the upper carbonate condensation level of the renowned Romualdo Formation.”

In their new study, Dr. Delcourt and collaborators from Brazil, Argentina, and Germany revised and compared the anatomy of Santanaraptor Placidus and Milischia asymmetrica to examine their phylogenetic relationships and potential synonymy.

Their analysis positions both species within an early-divergent group of maniraptoromorph dinosaurs, alongside Juratirant Rangami and Taniko Lagreus Topwilsoni, dating back to the Late Jurassic of Laurasia, indicating an early diversification of coelurosaurs in this region.

While there is some skeletal overlap, notable anatomical differences affirm their classification as separate species.

“The clade containing Juratirant Rangami, Milischia asymmetrica, Taniko Lagreus Topwilsoni, and Santanaraptor Placidus appears to extend back to at least Laurasia in the Late Jurassic, prior to the formation of the Apulian sea route that facilitated faunal exchange in the Early Cretaceous,” noted the paleontologists.

“At that time, a variety of coelurosaurs existed in both Laurasia and Gondwana, including Megaraptorra and branches such as ornithomimosaur, alvarezaurid, and dromaeosaurid.”

“Our phylogenetic model aligns more closely with the existing biogeographical data than one that confines Romualdocoelurosaurids primarily within Laurasian compsognathids or tyrannosaurids.”

“However, further studies and extensive fieldwork are necessary to clarify the early radiation of Coelurosaurus and its affinities with Romualdo morphology.”

A paper detailing these findings was published on November 18, 2025, in Anatomical Records.

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Rafael Delcourt and colleagues. Coelurosaurian theropods of the Romualdo Formation of the Early Cretaceous (Aptian) of Brazil: Santanaraptor Placidus meets Milischia asymmetrica. Anatomical Records, published online on November 18, 2025. doi: 10.1002/ar.70085

Source: www.sci.news

Bolivian Fossil Site Captures Thousands of Cretaceous Dinosaur Footprints, Tail Marks, and Swim Trails

The Carreras Pampas archaeological site within Bolivia’s Toro Toro National Park has documented 1,321 tracks and 289 isolated footprints, totaling 16,600 theropod dinosaur footprints. Additionally, 280 swim tracks have been identified, amounting to 1,378 swim tracks in total. Some of the tracks include tail traces.



Dinosaur footprints at the Carreras Pampas Stadium in Bolivia’s Toro Toro National Park. Image credit: Esperante et al., doi: 10.1371/journal.pone.0335973.

Bolivia boasts one of the most comprehensive and diverse records of dinosaur footprints globally, covering the Triassic, Jurassic, and Cretaceous periods.

Despite the abundance of track sites, there has been limited scientific research published.

A recent study led by paleontologist Raul Esperante from the Institute of Geosciences, along with his colleagues, has documented an extraordinary variety of dinosaur footprints at the Carreras Pampas site in Toro Toro National Park.

In nine different study areas, the research team uncovered 16,600 footprints left by three-toed theropod dinosaurs from the late Cretaceous.

These footprints vary in size from small (less than 10 cm) to large (over 30 cm) and capture a range of dinosaur behaviors, including running, swimming, tail dragging, and abrupt turns.

“The waist height of most (80%) of the trackmakers was between 65 cm and 1.15 meters, with a significant portion measuring between 75 cm and 1.05 meters,” stated the paleontologist.

“Interestingly, very few trackmakers exceeded 1.25 meters in height.”

The majority of these footprints are oriented approximately northwest to southeast, and the sediments retain ripple marks, indicating that these dinosaurs traversed ancient shorelines.

“The Carreras Pampas track set a new world record for the number of individual dinosaur footprints, continuous tracks, tail marks, and swimming marks,” the researchers noted.

“This exceptional frequency suggests it was a heavily trafficked area, and the parallel alignment of some footprints may imply groups of dinosaurs traveled together.”

“Numerous more footprints at this site and other locations in Bolivia remain to be studied,” they added.

“This site offers a remarkable glimpse into the region’s past. It reveals not only how many dinosaurs inhabited the area but also their behaviors during migration.”

“It’s truly incredible to work here, as the ground is covered with dinosaur footprints wherever you look.”

The team’s findings were published in the online journal PLoS ONE.

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R. Esperante et al. 2025. Morphology, preservation, and taphonomy of dinosaur footprints, tail prints, and swim tracks in the world’s largest athletic arena: Carreras Pampas, Toro Toro National Park, Bolivia (Upper Cretaceous). PLoS One 20 (12): e0335973; doi: 10.1371/journal.pone.0335973

Source: www.sci.news

New Research Reveals Dynamic, Regionally Unique Communities of Late Cretaceous Dinosaurs

The most renowned mass extinction in Earth’s history occurred approximately 66 million years ago. A swift decline in environmental conditions resulted in the extinction of around 75% of species, including the most famous non-avian dinosaurs, and the eventual restoration of terrestrial ecosystems. The ongoing debate focuses on whether dinosaurs vanished abruptly while they were still diverse and thriving or whether they experienced a prolonged decline by the end of the Cretaceous.



Flynn and colleagues analyzed Alamosaurus fossils found in northwestern New Mexico, revealing that these dinosaurs, while very different, are contemporaneous with those discovered further north in Wyoming and Montana. Image credit: Natalia Jagielska.

The geological formations of northwestern New Mexico hold a concealed chapter of Earth’s history.

Paleontologist Daniel Peppe from Baylor University and his team have uncovered indications of a flourishing dinosaur ecosystem in the Kirtland Formation’s Naashoibito Formation just prior to the asteroid impact.

Utilizing high-precision dating methods, they established that the fossils in these formations range from 66.4 to 66 million years old.

“The Naashoibito dinosaur coexisted with the renowned Hell Creek species of Montana and the Dakotas,” Dr. Peppe remarked.

“They were not in decline; rather, they constituted a vibrant, diverse community.”

The discoveries in New Mexico challenge previous assumptions.

Instead of being uniform and weakened, dinosaur communities across North America were unique and thriving in their respective regions.

Through ecological and biogeographic analysis, the researchers determined that dinosaurs in western North America thrived in distinct biozones shaped by regional temperature variations, rather than geographical barriers like mountains or rivers.

“Our recent study indicates that dinosaurs were not on the brink of mass extinction,” stated Andrew Flynn, a researcher at New Mexico State University.

“They were thriving, but the asteroid impact ultimately led to their demise.”

“This contradicts the long-established notion that a gradual decline in dinosaur diversity precipitated mass extinction, making them more susceptible to extinction.”

“The asteroid impact briefly terminated the age of dinosaurs, but the ecosystem they left laid the groundwork for what followed.”

“Within 300,000 years post-extinction, mammals began to diversify rapidly, branching into new diets, body sizes, and ecological roles.”

“The same temperature-driven patterns that influenced dinosaur communities carried into the Paleocene, illustrating how climate influenced the rebirth of life following catastrophic events.”

“The surviving mammals continued to exhibit distinct northern and southern biological regions.”

“Mammals from the north and south are markedly different from each other, diverging from other mass extinctions, which tend to appear more uniform.”

Of findings posted in today’s edition of Science.

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Andrew G. Flynn et al.. 2025. Late-surviving neo-Mexican dinosaurs reveal Cretaceous superlative diversity and locality. Science 390 (6771): 400-404; doi: 10.1126/science.adw3282

Source: www.sci.news

New Cretaceous Crocodile Species Discovered in Montana

Paleontologists have discovered a new species of extinct crocodile-like creature from fossilized remains found in southwest Montana, USA.



Impressions of the artist Thikarisuchus Xenodentes. Image credits: Dane Johnson/Rockies Museum.

The newly identified species existed at the edge of the ancient western inland sea around 95 million years ago, during the late Cretaceous period.

It has been named Thikarisuchus Xenodentes, a type of neostian.

“Measurements indicate it was less than 60 cm (2 feet) from nose to tail tip,” stated David Barilisio, a professor at Montana State University. “If it had grown fully, it could have reached about 90 cm (3 feet) or more, but still much smaller than most members of the Neosuchia clade to which it belongs.”

“This clade includes modern crocodiles and their closest extinct relatives, most of which are semi-aquatic or marine carnivorous animals with simple cone-shaped teeth.”

In contrast, Thikarisuchus Xenodentes likely lived on land and possibly fed on plants, insects, and small animals, possessing a variety of tooth shapes.

“Its unique anatomy indicates it is part of a newly identified family of crocodile-like creatures endemic to the Cretaceous in North America.”

The fossilized remains of Thikarisuchus Xenodentes—including its limbs, vertebrae, jaw, and a skull measuring 50 mm—were discovered in the US Forest Service Black Reef Formation near Dillon, Montana, in the summer of 2021.

“We previously found dinosaurs in the Black Reef Formation, making this the second known vertebrate species discovered in this layer,” remarked Harrison Allen, a doctoral student at Stony Brook University.

Paleontologists found the bones of Thikarisuchus Xenodentes in a densely packed arrangement consistent with the fossils of other living creatures found in the dens of the Black Reef Formation and nearby Wayan Formation in Idaho.

“This supports the idea that Thikarisuchus Xenodentes was preserved in dens and that fossils from these layers are biased toward those found in such environments,” they noted.

The specimen also suggested connections to a newly established family group, wannchampsidae, and a related group identified in Eurasia, known as the Atopasauriaceae.

Both families were small, globally adaptive, and exhibited specific skull and dental characteristics shared with more distantly related groups from the Cretaceous period in Africa and South America.

“We propose that shared environmental conditions and prey availability led to convergent evolution between these two distantly related groups during the same timeframe.

“The vast majority of alligatorid diversity belongs to the past, including fully marine crocodiles, entirely terrestrial crocodiles, herbivorous, omnivorous species, and those with unique shells.”

“This discovery surprised me and motivated my interest in this specific field of paleontology.”

A paper detailing the findings is published in the Journal of Vertebrate Paleontology.

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Harrison Allen et al. 2025. The impact of newly discovered small heterodonneostians and heterodonneostians in southwestern Montana’s Black Leaf Formation on paleoecology. Journal of Vertebrate Paleontology in press; doi: 10.1080/02724634.025.2542185

Source: www.sci.news

Fossils from the Early Cretaceous Period at the Swiss Museum

Paleontologists have identified a new species within the extinct turtle genus Craspedochelys, based on some remarkable fossil shells and subsequent bones discovered in Colombia.



Artistic reconstruction of Craspedochelys Renzi and the shallow marine ecosystem it inhabited. The flip-like shape of the forelimbs is inspired by the most complete known specimen of Thalassemys bruntrutana. Image credit: Juan Guilard.

Craspedochelys Renzi thrived during the early Cretaceous Hauterivian period, approximately 132 to 125 million years ago.

This ancient species belonged to the Thalassocheridia, a group of marine-adapted turtles from the Jurassic and Cretaceous eras.

“Throughout their evolutionary journey, various unrelated turtle groups have developed adaptations for marine and coastal habitats,” says Dr. Edwin Alberto Cadena, a paleontologist at the Smithsonian Tropical Research Institute of Natural History.

“One such group is the Thalassocheridia, traditionally classified into three Jurassic families: Eurysternidae, Plesiochelyidae, and Thalassemydidae, which have complex and often debated phylogenetic relationships.”

“Among these families, the ‘Plesiochelyidae’ is particularly diverse, encompassing at least ten species across four different genera: Craspedochelys, Plesiochelys, Portlandomys, and Tropidemys.”

“The shells of ‘Plesiochelyids’ can be distinguished from other thalassocheridians by their large size (40-55 cm in shell length), with adults lacking the thyroid cortex of the hanging skin, typically displaying only a thick layer of fontanel in the center.”



Craspedochelys Renzi is characterized by a distinct shell featuring several occipital bones. Image credits: Cadena et al. , doi: 10.1186/s13358-025-00394-1.

The fossil specimen of Craspedochelys Renzi was first discovered by Swiss geologist Otto Lenz during a field expedition in the Cunja de Cuisa region of Guazila Province, Colombia, in the 1950s.

This specimen included partial shells measuring 25.5 cm long and 23.1 cm wide, along with hind limb bones and caudal vertebrae.

It was later stored in the paleontological collection of the Naturhistorisches Museum Basel in Switzerland, where it remained unnoticed for over 60 years among the fossil invertebrate collection.

“Geological evidence connects these specimens to shallow marine sediments from the Moina Formation, dating to the Hauterivian,” the paleontologist explained.

This fossil represents the youngest known occurrence of Thalassocheridians globally during the Hauterivian, and it is the second record from a non-European group.

“The discovery of Craspedochelys Renzi will greatly enhance our understanding of Thalassocheridians, particularly the ‘Plesiochelyidae’, expanding their geographical range to North Gondwana and temporal range to the Hauterivian,” the researchers stated.

“This find underlines the significance of reevaluating historical collections and the potential for future discoveries in less explored areas such as northern South America.”

“The existence of Craspedochelys Renzi in the Moina Formation further underscores the intricate paleobiogeographic history of early Cretaceous coastal habitats and marine turtles.”

“It also offers new perspectives on the evolutionary dynamics of Thalassocheridia and the still unresolved, unstable phylogenetic relationships within the group, which necessitates further detailed investigation in future research.”

The discovery of Craspedochelys Renzi is discussed in a paper published in the Swiss Journal of Palaeontology.

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ea. Cadena et al. 2025. The first occurrence of the “Plesiochelyidae” turtle in the early Cretaceous period of South America. Swiss J Palaeontol 144, 52; doi:10.1186/s13358-025-00394-1

Source: www.sci.news

Early Cretaceous Iguanodontian Dinosaurs Could Strike Their Sails

A new genus and species of sailed Iguanodontian dinosaurs has been discovered from a partial skeleton unearthed in the Wessex Formation on the Isle of Wight, England.

Restoration of Istiorachis macarthurae. Image credit: James Brown.

Named Istiorachis macarthurae, this new dinosaur species thrived in what is now England during the early Cretaceous period, approximately 125 million years ago.

These ancient creatures were part of a large, widely distributed group of herbivorous dinosaurs known as iguanodontians.

“Iguanodontia represented a highly successful clade of Ornithischian dinosaurs,” said Jeremy Lockwood, a paleontologist from the University of Portsmouth and the Museum of Natural History in London.

“By the end of the Cretaceous, they dominated the dinosaur fauna of Laurasia, alongside the hadrosaurid family, including Edmontosaurus legatus and Parasaurolophus walkeri.”

“While diversity among iguanodonts was low during the late Jurassic, it surged in the early Cretaceous.”

The most notable characteristic of Istiorachis macarthurae is a series of elongated spines along its back and tail, which formed a large sail-like structure.

“Evolution often favors the extravagant over the practical,” Lockwood commented.

“The precise function of such structures has been debated for years; however, while they may serve purposes from heat regulation to fat storage, visual signaling—perhaps for sexual display—seems the most plausible explanation in this context.”

“In modern reptiles, such sail structures are often more pronounced in males, indicating that these traits may have evolved to attract mates or intimidate rivals.”

“We hypothesize that Istiorachis macarthurae may have done something similar.”

Paleontologists closely examined the fossilized bones to determine the purpose of the sails.

By creating a comprehensive database of similar dinosaur backbones through direct observations, photographs, scientific illustrations, and reconstructions, they were able to investigate the evolutionary history of the back structure in this new Iguanodontian family tree.

This helped identify broader trends in the evolution of these sails.

“These methods allow us not only to explain the fossil evidence but also to test hypotheses about their function,” Lockwood noted.

“We demonstrated that Istiorachis macarthurae‘s spines were not only taller but also more exaggerated compared to typical Iguanodon features, making it an ideal candidate for traits arising through sexual selection.”

Istiorachis macarthurae illustrates a broader evolutionary pattern.

Research indicates that the lengthening of neural spines in the Iguanodon lineage began in the late Jurassic period, becoming more common in the early Cretaceous.

However, true hyperelongation, which surpasses four times the height of the spine body, remains rare.

Similar displays can be observed in present-day reptiles, such as various lizard species, where elaborate crests and sails often communicate health and strength to potential mates.

Istiorachis macarthurae is a prime example,” Lockwood said.

The findings were published in the journal Paleontology Papers this week.

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Jeremy A. F. Lockwood et al. 2025. The origin of neural spine elongation in Iguanodontian dinosaurs and the osteology of the new sail-backed dinosaur (Dinosaur, Ornithischia) from the Cretaceous Wealden group in England. Paleontology Papers 11(4): E70034; doi: 10.1002/spp2.70034

Source: www.sci.news

Home to Large-Horned Lizards and Armored Cretaceous Dinosaurs in North America.

Recently discovered fossil specimens of the Monsters include new genera and species, Borguamondor, found in southern Utah’s magnificent Kaiparowitz Formation at Escalante National Monument. These specimens highlight the remarkable diversity of these large lizards during the late North American period.



Reconstruction of Borguamondor‘s life. Image credit: Cullen Townsend.

Borguamondor existed in North America during the Cretaceous Campania period, approximately 72 million years ago.

These ancient reptiles represent a portion of the evolution of large-bodied lizards known as the Monsters. One of the most notable examples is the Gira monster, which still inhabits deserts where new species have been rediscovered.

“According to Monster Aurus Hank Wooley, a paleontologist at the Dinosaur Institute:

“They have a lineage spanning about 100 million years, but their fossil records remain largely incomplete. Discoveries like Borguamondor are significant in understanding these remarkable lizards, which would have appeared monstrous to us.”

“With an estimated length of about 1 m (3 feet), depending on the size of the tail and body, it may have been even larger.”

“In comparison to modern lizards, it was a large creature, akin to a monitor lizard inhabiting the savanna.

Related skeletal remains of Borguamondor, including skulls, vertebrae, girdles, limbs, and osteoderm fragments, were discovered starting in 2005 at the Kaiparowits Formation in Utah.

“Dr. Randy Ilmith, a paleontologist at the University of Utah, commented on Borguamondor:

Other fossils retrieved by the team include heavily armored skull bones, suggesting that ancient, seasonally tropical forests in southern Utah were home to at least three distinct types of large predatory lizards.

“Despite their size, the skeletal remains of these lizards are incredibly rare; most fossil records are based on isolated bones and teeth,” noted Dr. Joe Celtic, a paleontologist at the Smithsonian Tropical Research Institute and Colorado State University.

“The exceptional fossil record of large lizards from the Grand Stair Escalante National Monument may indicate that they were a typical part of the dinosaur-dominated ecosystem in North America, playing a vital role as small predators hunting for eggs and smaller animals in Lalamidia forests.”

“The identification of this new species within the Monsters category suggests the potential for undiscovered large lizards from the late Cretaceous period,” the researchers remarked.

“Moreover, this discovery underscores that there remains untapped diversity yet to be uncovered both in the field and within paleontological collections.”

“The closest known relatives of Borguamondor are found across the planet in the Asian Gobi Desert.”

“It has been widely recognized that these creatures traversed the former Cretaceous continents, which were once interconnected. The discovery of Borguamondor suggests that smaller animals also migrated, indicating a broader biogeographical pattern among terrestrial vertebrates during this era.”

Survey results will be published in the journal Royal Society Open Science.

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C. Henrik Woolley et al. 2025. New specimens of Monstaurus from the Kaiparowitz Formation in Utah reveal the unexpected diversity of ancient large lizards in late North America. R. Soc. Open SCI 12(6): 250435; doi: 10.1098/rsos.250435

Source: www.sci.news

Cretaceous Marine Deposits Reveal Evidence of a Massive Ancient Tsunami

Significant amber deposits found in northern Japan may have been propelled from the forest into the sea by tsunamis occurring between 116 million and 114 million years ago during the early Cretaceous period. This is according to a recent study conducted by geological surveys at Japan and Chuo University.

Amber deposits from Sichuan Quarry in Hokkaido, northern Japan. Image credit: Kubota et al. , doi: 10.1038/s41598-025-96498-2.

Identifying traces of ancient tsunamis can be challenging, as the powerful waves tend to reshape coastlines. The sediment left behind often resembles deposits created by other high-energy events, like storms.

Nevertheless, amber, which originates on land and is then transported to the sea, acts as a historical record of tsunami occurrences, illuminating the physical processes influencing sediment movement during these events.

“A tsunami is a destructive ocean wave primarily caused by significant changes in submarine or coastal crust, as well as impacts from asteroids,” explains Dr. Aya Kubota, a researcher at geological surveys at Japan and Chuo University.

“They have been extensively studied during the Holocene (the last 11,700 years) due to their relevance in disaster prevention.”

“Aside from asteroid sediments, accurately identifying ancient tsunamis before major vegetation growth is extremely difficult for two key reasons.”

“First, coastal tsunami deposits are easily eroded in their dynamic environments. Second, well-defined criteria for identifying tsunami deposits have not been established, as they can be difficult to differentiate from other high-energy coastal events, such as cyclones.”

In their research, Dr. Kubota and colleagues examined amber-rich silica deposits from the Shiko River Quarry in northern Hokkaido, which formed during the early Cretaceous period around 115 million years ago.

Using fluorescence imaging, the authors discovered that the amber samples exhibited clear deformation in what is known as the flame structure. This occurs when the amber is still pliable at the time of deposition, allowing it to change shape before solidifying.

This suggests that a substantial quantity of amber was swiftly transported from land into the open ocean due to the backwash from one or more tsunamis, experiencing minimal exposure to air.

The amber then settled at the seabed, becoming covered with a layer of silt, which helped to preserve it.

“Other terrestrial sediments carried into open water could be instrumental in studying significant ancient catastrophic events, such as tsunamis,” the researchers concluded.

Their study was published in the journal Scientific Reports on May 15th.

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A. Kubota et al. 2025. Amber, a deep-sea sediment from the Cretaceous period, reveals a massive tsunami. Sci Rep 15, 14298; doi:10.1038/s41598-025-96498-2

Source: www.sci.news

Mammals evolved to thrive on land in the late Cretaceous period.

A recent study conducted by the University of Bristol presents evidence that many mammals had already transitioned towards a more ground-based lifestyle prior to the final Cretaceous mass extinction that eradicated the non-avian dinosaurs 66 million years ago.



Dryolestes late Jurassic relatives of Cretaceous treatment mammals. Image credits: James Brown/Pamelagill/University of Bristol.

Present-day mammals thrive in a varied environment mainly dominated by angiosperms (flowering plants).

In contrast to the habitats provided by coniferous vegetation, forests and woodland environments possess intricate lower levels and towering trees, offering rich biodiversity and resources for terrestrial mammals of all sizes.

Yet, the angiosperm-dominated habitat is relatively recent in Earth’s history, primarily characteristic of the Cenozoic era (66 million years ago to the present), with initial developments towards the end of the Cretaceous period.

“Mesozoic mammals were typically small, mostly weighing under 5 kg, with few surpassing 10 kg,” noted Professor Christine Janice from the University of Bristol and a colleague.

“While it holds true that the majority of present-day mammals are small, averaging around 0.5 kg, the Cenozoic era saw the evolution of greater mammal diversity.”

“The small size of Mesozoic mammals has commonly been attributed to dinosaur predation, but recent recognition of the late Cretaceous proliferation of angiosperms and the habitats they offered may be more crucial than dinosaurs in elucidating the patterns of Mesozoic mammal evolution and diversification.”

“Did these mammals prefer trees or terrestrial substrates? And did this preference alter towards the close of the Cretaceous period with the changes in angiosperm habitats?”

In their research, the authors scrutinized tiny bone fragments of ancient mammalian taxa (marsupials and placentals) unearthed in western North America, specifically the extremity bone edges.

They identified indications that these mammals were adapting to a terrestrial lifestyle.

The analysis of extremity bone edges entailed signatures of locomotive patterns that could be statistically compared to modern mammals.

“There was a known shift in plant life towards the Cretaceous boundary, characterized by angiosperms,” stated the researchers.

“It was also acknowledged that arboreal-dwelling mammals faced challenges post-asteroid impact.”

“However, what remained undocumented was whether mammals were inclining towards a more ground-dwelling lifestyle alongside habitat transformations.”

Former studies utilized complete skeletons to study the movement patterns of ancient mammals, but this study was among the first to employ small bone elements to track alterations across the community.

“The plant habitat appears to have played a pivotal role in the trajectory of Cretaceous mammal evolution beyond dinosaur influences,” remarked Professor Janice.

Published in the March/April 2025 issue of the journal Paleontology, the study unveils intriguing insights into ancient mammal adaptations.

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Christine M. Janice et al. 2025. Paleontology 68(2): E70004; doi: 10.1111/pala.70004

Source: www.sci.news

The Cretaceous period larvae possessed advanced eyes

Paleontologists have discovered three racewing larvae in Myanmar's 100 million Kachin amber with large forward trunks (the eyes of Holometabolan). These specimens show highly developed, simple eye convergent evolution of at least two additional lines, indicating the enormous diversity of Cretaceous larvae.

A larva from Kachin Amber, 100 million years ago. Image credit: Haug et al. , doi: 10.1111/1744-7917.13509.

Adult insects are known for their fascinating and complicated eyes. This allows you to achieve amazing sensory feats when performing functions such as food and peers search.

However, in many insect larvae, these eyes are not yet developed. The simple eyes known as the stem are usually sufficient for these larvae. Often, it is a machine that is mostly eating at this stage.

However, some insect larvae are predators, and a few of these have developed highly efficient imaging systems from simple stems.

“The adults and pups of beetles, bees, flies, butterflies and close relative insects also have complex eyes that are present in some larvae,” says Dr. Carolin Haug, researcher at Ludwig-Maximilians-Universität München.

“In contrast, most holometaboran larvae have a small group of up to seven simple eyes, known as stems, on either side of the head.”

“The trunk is inherent to holometaborane, usually a simple structure, often slightly radial oriented, creating a wide field of view.”

“However, the fields of the right and left trunks rarely overlap, but denies binocular vision in the larvae.”

“And more, most stems lack the complex internal structures needed to create images.”

“In contrast, several predatory holometaboran larvae evolved anteriorly directed stems, which were expanded with overlapping fields of vision that promote binocular vision.”

“Examples include the larvae of diving beetles known as water tigers, tiger beetles, anthraion and the Whirlgihi beetle.”

“The trunk has been reported in over 120 fossil larvae, but no imaging eyes have been identified that allow binocular vision.”

In a new study, the authors discovered three predatory larvae with unusually large and positive trunks in the Cretaceous Cachin Amber.

They found that the size and orientation of the larvae eyes are comparable to the size and orientation of modern anthraions, allowing for similar optical resolution.

“This is evidence of the first fossils of such an eye and therefore the oldest,” Dr. Haug said.

“The highly refined, simple eyes of predatory larvae evolved with a further double convergence, not just anti-, water tigers and tiger beetles, but also at least among extinct larvae.”

“Our results reveal greater diversity in morphology, ecology, and feeding strategies among Cretaceous larvae than today.”

Survey results Published in the journal Insect Science.

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Karolyn Haug et al. Cretaceous horny larvae with binocular vision show convergent evolution of refined, simple eyes. Insect SciencePublished online on February 18th, 2025. doi:10.1111/1744-7917.13509

Source: www.sci.news

The Mighty Hidden Muscle Dinosaurs that Roamed Cretaceous European Islands

New genus and species of Titanosaurus have been identified from fossilized sites found in the Hayeg Basin, Transylvania, western Romania.

The artist's impression of the lithotrothian dinosaur herd (right). Image credit: Abelov/CC by 3.0.

The newly identified species was alive Haeg IslandA large subtropical land located in the Thetis Sea about 70 million years ago (Cretaceous).

dubbing uriash kadicithe animals belong to Lithostrotiaa group of titanosaurus dinosaurs containing many armored species.

“The sauropod dinosaurs on Titanosaurus include the largest animal walking on land, with a huge species of over 60 tons,” says Paleoliths at the Museum of Fool Naturkunde, a Livenitz Installation Fool Evolution. said Dr. Veronica Dees Diaz, a scholar. colleague.

“By the late Cretaceous, Titanosaurus had achieved almost global distribution.

“Despite the rich and global fossil record, the evolutionary relationships of Titanosaurus are less known, limiting our understanding with this diverse megaharbibaud (the only group of sauropods is , the only group to survive the latest Cretaceous period).

“European giants in particular have been largely ignored in phylogenetic analysis,” they said.

“This neglect comes mainly from the historical advantages of the Gondwana species and the rarity and imperfection of Laurasian artefacts, particularly from Europe.”

“However, this began to change with the combination of reassessment of existing species and specimens and the discovery of new sites with distinct partial skeletons.”

“As a result, the fossil records of the most recent Cretaceous European sauropods are increasingly important for biogeographical scenarios, and rich evolutionary history is increasingly recognized for increasing incorporation into phylogenetic analysis. It is beginning to make clear.

Holotype of uriash kadici It was discovered in the formation of density in the Hayeg Basin, Romania.

Dinosaurs are estimated to weigh between 5 to 8 tons and their body length is close to 12 m.

uriash kadici It is the largest titanosaurus species known from the Ha eg basin, exceeding the maximum reached by most other late Cretaceous European Titanosaurus. Abitosaurus (Estimated at 14 tons and 17.5 m long)”, the paleontologist said.

The existence of large giants such as ” uriash kadici It is worth noting and requires explanation as it appears to contradict, or at least weaken, the supposed behavior of “island domination” over these faunas. ”

uriash kadici It coexists with three other Titanosaurus species. Majarosaurus Dax, PaluditiTan nalatzensis and Petrustitan Hungarian.

The diversity was probably even higher, as evidenced by the substantial amounts of fossils involved.

“Our phylogenetic analysis shows that these Transylvanian titanosaurus exhibit particularly close relationships with Gondwana species. Majarosaurus Retrieved as a member or relative of the Saltasauria family. Palditian Affinity with lognkosauria and the Spanish Titanosaurus that were almost the same era Lohuecotitan; Petrustitan It is most closely related to early branched eutitanosaurian species in South America. and Uriash We share a unique feature with Gondwanan Titanosaurs,” they said.

“These analyses also reinforce the paleobiogeographic hypothesis that the latest Cretaceous European giants were members of the Gondwana lineage that invaded the old regions during the ages of Valemia and Albia.”

“Since the first discovery, Majarosaurus Dax The island's dwarfs have been identified as star sauropods, proposed as explanations for the small size of this species and other dinosaurs on Hayeg Island. ”

“on the other hand Palditian and Petrustitan It is also a small body sauropod. Uriash It is several orders of magnitude heavier and represents one of the largest Titanosaurus species found in the Late Cretaceous period of Europe. ”

“We have shown that the existence of this body size disparity is ecologically excluded from body size reduction due to competition with small-body titanosaurus, or as evidence that some lineages and small We interpret it as evidence that it occurred early in stratigraphically among the giants of the body. Hayeg Island has descendants of existing dwarf ancestors.”

“In contrast to some previous studies, signs of titanosaurus leaving the body size, including swapping the War star species for larger-sized species during the top Cretaceous period of the Transylvanian region. I can't see it.”

Discovery of uriash kadici Reported in a paper It was released this month Journal of Systematic Palaeontology.

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Veronica Dies Dias et al. 2025. The Romanian sauropod dinosaur revision reveals high titanosaurus diversity and body size disparities on Hayeg Island of Titanosaurus, affecting the biogeography of Titanosaurus. Journal of Systematic Palaeontology 23(1): 2441516; doi: 10.1080/14772019.2024.2441516

Source: www.sci.news

Abyssaurid birds from the Cretaceous era might have hunted similar to present-day hawks and owls

Paleontologists have explained three new things Enantiornithine Cretaceous Hell Creek Formation birds, two of which are new species abysauridae seed. These birds lived alongside dinosaurs 68 million years ago, and their powerful leg bones suggest they may have captured and carried off prey.

Restoration of abyssaurids (e.g. Avisaurus Darwini). Image credit: Clark others., doi: 10.1371/journal.pone.0310686.

The most diverse bird species of the Cretaceous period was a now extinct group called the enantiornithines, which were known throughout the world during this period.

However, enantiornithines and other Mesozoic birds are known primarily from Early Cretaceous deposits, with records from the Late Cretaceous being relatively sparse.

Therefore, there is a general lack of understanding of the evolutionary trends of birds towards the end of the Mesozoic Era.

The fossilized remains of three new enantiornithine birds have been discovered in the Hell Creek Formation of Montana and date to the late Cretaceous period.

Two species were named new species. Magnusabis ekarakaensis and Avisaurus Darwiniwhile the third is an unnamed species. Avisaurus.

All of these birds were larger than the Early Cretaceous enantiornithines; Avisaurus Darwini It is estimated to weigh more than 1 kg, making it about the size of a large hawk.

“These discoveries virtually double the number of bird species known from the Hell Creek Formation and are important for a better understanding of why only some birds survived the mass extinction event. It will be.” tyrannosaurus and the abysaurid described here,” said Dr. Jingmai O'Connor, associate curator of fossil reptiles at the Field Museum.

When the team analyzed the leg bones, they found Avisaurus Hawks and owls and their relatives exhibit hawk- and owl-like proportions and adaptations, and, like some modern raptors, have powerful legs that can grasp and carry proportionately large prey. Shows muscles and legs.

“Based on clues in the leg bones, we think these birds were able to capture and transport prey, similar to modern hawks and owls,” said Dr. Alex Clark. students at the Field Museum and the University of Chicago.

“They may not have been the first raptors to evolve, but their fossils are the oldest known examples of predatory birds.”

This new species expands the known diversity of Late Cretaceous birds, confirms trends toward larger body sizes, and sheds light on how enantiornithines evolved a diversity of ecological roles over time. It's highlighted.

“Abyssaurids, the latest Cretaceous enantiornithid birds, display hindlimb features with strong ankle flexion, which contributes to the ability to carry heavy prey and similar behavior to modern raptors. “This suggests that,” the paleontologists said.

their paper Published in today's diary PLoS ONE.

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AD Clark others. 2024. New enantiornithine diversity of the Hell Creek Formation and functional morphology of avian tarsometatarsals. PLoS ONE 19 (10): e0310686;doi: 10.1371/journal.pone.0310686

Source: www.sci.news

Toothed birds in the Cretaceous era primarily consumed gymnosperm fruits, not fish.

Paleontologists found fossilized seeds of gymnosperms, relatives of today’s conifers and ginkgo trees, in the stomachs of two of the specimens. Longipteryx caoyangensis One of the oldest known birds, and also one of the strangest. This discovery shows that these birds ate fruit, despite the long-held assumption that they were fish eaters, and the more recent hypothesis that they ate insects with their incredibly strong teeth.

Skull Longipteryx caoyangensis Image courtesy of Xiaoli Wang.

Longipteryx caoyangensis It lived in what is now northeastern China during the Cretaceous period, about 120 million years ago.

First described in 2000, this ancient bird had a long skull and teeth only at the tip of its beak.

“Tooth enamel is the hardest substance in the body. Longipteryx” Human tooth enamel is 50 microns thick,” says Alex Clark, a doctoral student at the Field Museum and the University of Chicago.

“That’s the same thickness as the enamel of a large carnivorous dinosaur. Allosaurus It weighed 4,000 pounds. Longipteryx It was about the size of a blue jay.”

Scientists have previously found that the elongated skull of a kingfisher Longipteryx caoyangensis This means they hunted fish, but this hypothesis has been called into question by a number of studies.

“There are other fossil birds. Janornis “We know they ate fish because specimens have been found with preserved stomach contents, and fish tend to preserve well,” said Dr. Jingmai O’Connor, associate curator of fossil reptiles at the Field Museum.

“In addition, these fish-eating birds had many teeth throughout their beaks. Longipteryx “It only has teeth at the tip of its beak. That doesn’t make sense.”

but, Longipteryx caoyangensis In some cases, animals have been found with fossilized food still in their stomachs, allowing scientists to determine what they had been eating.

In the new study, paleontologists examined two new specimens of this species.

They found that the small round structures in the bird’s stomach Gymnosperms seed.

Since Longipteryx caoyangensis Since they lived in a temperate climate, it is unlikely that they ate fruit all year round.

The authors speculate that when fruit was unavailable, they may have had a mixed diet that included insects.

Longipteryx caoyangensis Part of a larger group of prehistoric birds called enantiornithines, the discovery marks the first time that scientists have found the stomach contents of an enantiornithine in China’s Jehol Biota, despite the discovery of thousands of fossils.

“It’s always puzzling not to know what they were eating, but this study points to a larger problem in palaeontology, which is that the physical characteristics of fossils don’t always tell the whole story about what animals were eating or how they lived,” Dr O’Connor said.

Since Longipteryx caoyangensis It apparently did not hunt fish, which raises the question of what it used its long, pointed beak and unusually strong teeth for.

“The thick enamel seems to be overpowering and weaponized,” Clark said.

“One of the most common skeletal parts that birds use in aggressive displays is the proboscis, or beak.”

“Using the beak as a weapon makes sense because it keeps the weapon away from the rest of the body and helps prevent injury.”

“Modern birds don’t have teeth, but there are some really cool little hummingbirds that have keratinous projections near the tip of their snouts. Longipteryx And they are using it as a weapon to fight each other,” Dr O’Connor added.

“Hummingbird beaks have evolved at least seven times, allowing them to compete for limited resources.”

of Survey results Published in the journal today Current Biology.

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Jinmai O’Connor others Direct evidence for frugivory in Mesozoic birds Longipteryx This is inconsistent with morphological indicators of diet. Current Biology Published online September 10, 2024; doi: 10.1016/j.cub.2024.08.012

Source: www.sci.news

New insights into the evolutionary origins of tardigrades from Cretaceous amber fossils

Tardigrades are a diverse group of microinvertebrates widely known for their remarkable ability to survive. Molecular clocks suggest that tardigrades diverged from other panarthropods (arthropods, tardigrades, velvet worms, and lobopods) before the Cambrian, but the fossil record is extremely poor. Now, paleontologists have described a new species of tardigrade and redescribed previously known species. readBoth are from Canadian Cretaceous amber.

Artistic Restoration read (Top) and Aerobius dactylus (Bottom) A hypothetical fossilization environment. Image courtesy of Franz Anthony.

First discovered in 1773, tardigrades are a diverse group of microscopic invertebrates best known for their ability to survive in extreme environments.

Also known as tardigrades or moss pigs, these creatures can live up to 60 years and grow to a size of up to 0.5mm. They are best seen under a microscope.

They can survive up to 30 years without food or water, and can survive temperatures as low as -272°C and as high as 150°C for a few minutes, and as low as -20°C for decades.

Tardigrades can withstand pressures ranging from nearly zero atmospheres in outer space to 1,200 atmospheres at the bottom of the Mariana Trench, and can also tolerate radiation levels of up to 5,000-6,200 Gy.

They survive by entering a state of suspended animation called biostasis, using proteins that form a gel inside the cells and slow down vital processes.

“Tardigrades are microscopic invertebrates characterized by a compact body shape with lobopod legs with four pairs of claws, and are closely related to the clawed pterygota and euarthropods. Panarthropods“Harvard doctoral student Mark Mapalo and his colleagues said:

“Tardigrades are widely known for having several species with cryptobiotic capabilities that allow them to survive extreme conditions such as the vacuum of space, ionizing radiation and freezing temperatures. Tardigrades are also found in marine, freshwater and terrestrial habitats around the world.”

“Despite their ubiquity in the modern biosphere, tardigrades have a notoriously poor fossil record, and research into their macroevolution, such as the origin of their body shape, the timing of their terrestrialization, and the acquisition of their cryptic abilities, is limited.”

“Currently, only four fossil crown-group tardigrades are known, all preserved as amber inclusions, but only two of these have an established taxonomic position relative to extant tardigrades.”

Aerobius dactylusImages/Photos: Mapalo others., doi: 10.1038/s42003-024-06643-2.

For the study, the authors looked at a piece of amber containing a tardigrade fossil that was discovered in Canada in the 1960s. read and what was presumed to be another tardigrade, which was virtually unexplained at the time.

Using confocal laser scanning microscopy, a technique commonly used to study cell biology, the researchers were able to examine the microscopic structure of the tardigrade fossils in astonishing detail.

This study read It has been identified as a new species in the Tardigrade family tree, Aerobius dactylus.

“Both were found in the same Cretaceous amber, which means that these tardigrades coexisted with dinosaurs,” said Dr Javier Ortega-Hernández of Harvard University.

read The seven claws are well preserved, and those that curve towards the body are smaller than those that curve away from it, a pattern seen in modern tardigrades.”

“The second, previously unidentified specimen had claws of equal length on each of the first three pairs of legs, but the outer claws on the fourth leg were longer.”

Both species serve as important calibration points for an analysis called a molecular clock analysis, which helps scientists estimate important evolutionary timing.

For example, new research suggests that modern tardigrades likely branched off during the Cambrian period, more than 500 million years ago.

The study also sheds light on the origins of tardigrades' remarkable ability to survive extreme environments by entering a state of torpor.

“This study estimates that this survival mechanism likely evolved during the middle to late Palaeozoic and may have played a key role in helping tardigrades survive the end-Permian mass extinction, one of the most severe extinction events in Earth's history,” Dr Ortega-Hernández said.

of result Published in a journal Communication Biology.

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MA Mapalo others2024. Inclusions in Cretaceous amber shed light on evolutionary origins of tardigrades. Communication Violet 7, 953; doi: 10.1038/s42003-024-06643-2

Source: www.sci.news

The mystery of Cretaceous shark hunting techniques revealed through detailed fossil analysis

Petitcodus shark fossil discovered in Mexico

Roman Vullo

A fossil shark that thrived during the Cretaceous period has been found and has shed light on how sharks hunted and their place on the evolutionary tree.

Fossil shark teeth Ptychodus have been in museums for over 200 years. While some members of this group grew to be enormous, the anatomy of others was largely unknown.

This lack of information left researchers uncertain about the shark’s overall appearance and feeding habits, but the wide, flat teeth suggest it was capable of eating hard-shelled prey.

Recently, Professor Roman Vullo at the University of Rennes in France discovered six well-preserved full-body fossils of Ptychodus in Mexico, placing the shark in the order Lamniformes alongside modern shark species like great whites and basking sharks.

What makes this discovery interesting is that while modern white sharks are known for hunting in open waters, Ptychodus were fast swimmers and voracious eaters in the open ocean, preying on armored pelagic fish like large ammonites and sea turtles.

Despite the small size of the studied specimens, estimated to be less than 3 meters long, researchers believe some members of the genus reached lengths of about 9.7 meters – twice the size of a great white shark. Females tended to be larger, measuring between 4.6 and 4.9 meters in length.

During the Cretaceous period, Ptychodus sharks played a significant role in the marine food chain. They likely competed with large marine reptiles with crushing dentition, which may have led to their extinction before the end-Cretaceous extinction event.

topic:

Source: www.newscientist.com

New Middle Cretaceous paleoclimate insights from dinosaur footprints in the Nanushuk Formation

Paleontologists investigated dinosaur footprints and large assemblages of fossilized plants. Nanushuk FormationIt extends over much of the northern slope of central and western Alaska, varying in thickness from 1,500 to 250 m (4,921 to 820 ft) from west to northeast.

Theropod dinosaur footprints in the Nanushuk Formation, Alaska, USA. Note the sinusoidal shape of the metatoe impression. Scale bar – 10 cm.Image credit: Fiorillo other., doi: 10.3390/geosciences14020036.

“For the past 20 years, Alaska has been working on projects that integrate sedimentology, dinosaur paleontology, and paleoclimate indicators,” said Paul McCarthy, a professor at the University of Alaska Fairbanks.

“We've been studying the other three formations, Denali, the North Slope, and southwestern Alaska, and they're about 70 million years old.”

“This new one is in strata that are about 90 million to 100 million years old.”

“What we were interested in looking at rocks from this age is that this is about the same time that people thought the Bering Land Bridge connecting Asia and North America began.”

“We want to know who was using it, how they were using it, and what the circumstances were.”

“The mid-Cretaceous period was the hottest period of the Cretaceous period.”

“The Nanushuk Formation gives us a snapshot of what high-latitude ecosystems look like on a warm Earth.”

The Nanushuk Formation dates from the mid-Cretaceous period, approximately 94 to 113 million years ago, at the beginning of the Bering Land Bridge.

The field survey was conducted between 2015 and 2017, focusing on the Cork Basin, a circular geological feature of the formation.

The basin is located at the base of the Delong Mountains along the Kukpouluk River, approximately 100 km (60 miles) south of Point Rey and 32 km (20 miles) inland from the Chukchi Sea.

In the area, paleontologists found about 75 fossilized footprints and other traces of dinosaurs believed to have lived along rivers and deltas.

“This place had so many dinosaur footprints. One site stands out,” said Dr. Anthony Fiorillo, a researcher at the New Mexico Museum of Natural History and Science.

“We eventually realized that we were walking over an ancient landscape for at least 400 yards (366 meters).”

“In that landscape, we found large upright trees with smaller trees between them, with leaves on the ground. There were footprints on the ground, and there was fossilized feces.”

“We found numerous fossilized tree stumps about 60 centimeters (2 feet) in diameter. It felt like we were walking through a forest that was millions of years old.”

Although the Nanushuk Formation includes rocks of marine and non-marine characteristics and composition, the new study focuses primarily on non-marine sediments exposed along the upper Kukpouluk River.

“One of the things we did in our paper was look at the relative frequencies of different types of dinosaurs,” Dr. Fiorillo said.

“What was interesting to us was that bipedal plant-eating animals were clearly the most common.”

Two-legged plant-eating animals accounted for 59% of all footprints discovered. 17% were four-legged plant-eating dinosaurs, 15% were birds, and 9% were non-avian, mainly carnivorous bipedal dinosaurs.

“One of the interesting things is the relative frequency of bird tracks,” Dr. Fiorillo said.

Carbon isotope analysis of wood samples revealed that the area received approximately 70 inches (178 cm) of rainfall per year.

This record of increased precipitation during the Mid-Cretaceous provides new data supporting global precipitation patterns associated with the Mid-Cretaceous. Cretaceous thermal maximum.

The Cretaceous thermal maximum was a long-term trend about 90 million years ago, during which average global temperatures were significantly higher than today.

“Temperatures were much warmer than today, and perhaps more interestingly, we had a lot of rain,” Dr. Fiorillo said.

a paper Survey results are published in a magazine earth science.

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Anthony R. Fiorillo other. 2024. New dinosaur ichthyological, sedimentological, and geochemical data from the Nanushuk Formation of Alaska's North Slope, a Cretaceous high-latitude terrestrial greenhouse ecosystem. earth science 14(2):36; doi: 10.3390/geosciences14020036

Source: www.sci.news

The pioneering toothless beak of the Cretaceous enantiornithine bird

Paleontologists have described a new species of enantiornithine bird with a toothless beak from the Chinese Jehor bird family. This discovery delayed the earliest appearance of edentulism (lack of teeth) in enantiornithines by about 48 million years.

fossil skeleton of Impalavis Attenborough and bird restoration. Image credit: Ville Sinkkkonen / Wang other., doi: 10.1016/j.cretres.2024.105867.

Impalavis Attenborough They lived in what is now northeastern China about 120 million years ago (early Cretaceous period).

This bird was a member of a group called. enantiornis, or “the opposite bird.” It is named for the feature of its shoulder joint that is “opposite” to that found in modern birds.

Enantiornithines were once the most diverse group of birds, but became extinct 66 million years ago following a meteorite impact that wiped out most dinosaurs.

Paleontologists are still working to understand why enantiornithids went extinct and the birds that gave rise to modern birds survived.

“The enantiornithines are very strange. Most of them had teeth and still had clawed fingers,” said Dr. Alex Clark. student at the University of Chicago and the Field Museum.

“If you were to travel back in time to northeast China 120 million years ago and walk around, you might have seen something that looked like a robin or a cardinal. But it had an open mouth and a bunch of teeth. . When you lift your wings, you’ll notice that you have little fingers.”

“Scientists previously thought that the first record of this group without teeth was from the late Cretaceous period, about 72 million years ago.”

“This little man is Impalavis Attenborough, pushing it back about 48 to 50 million years. Therefore, the lack of teeth, or edentulism, developed much earlier in this group than we thought. “

fossilized skeleton Impalavis Attenborough It was discovered by an amateur fossil collector near the village of Toudaoyingzi in northeastern China and donated to the Tianyu Natural Museum in Shandong Province.

“I think what attracted me to this specimen was the forelimbs, not the lack of teeth,” said Dr. Jingmai O’Connor, associate curator of fossil reptiles at the Field Museum.

“It had a huge bicrest, and a bony protrusion on top of the upper arm bone that had muscles attached to it.”

“I had seen such emblems on birds from the Late Cretaceous period, but never in the Early Cretaceous period like this one. That’s when I first suspected that it might be a new species. It was.”

rare wing bones Impalavis Attenborough Muscle attachments that allowed this bird to flap its wings with extra force may have been possible.

“We’re looking at potentially very strong wingbeats,” Clark said.

“Some of the bone features are similar to those of modern birds such as puffins and murres, which can flap their wings at crazy speeds, or of birds such as quail and pheasants. Although they are small birds, they generate enough force to instantly fly almost vertically when threatened.”

On the other hand, a toothless beak Impalavis Attenborough Modern toothless birds have a wide variety of diets, so researchers aren’t necessarily sure what they ate.

Like its fellow enantiornithines, and unlike modern birds, it does not appear to have a digestive system called a gizzard or gastric mill to help grind up its food.

“Although most enantiornithines appear to have been quite arboreal, differences in forelimb structure suggest that Impalavis Attenborough Although it probably still lived in trees, it probably went down to the ground to feed, and it had a unique diet compared to other enantiornithines. This suggests that there is a possibility, and that it may also explain why they lost their teeth.” said Dr. said Connor.

In their study, the scientists also reexamined previously known bird fossils. Chiapiavisand suggests that it was also an early toothless enantiornithine.

“This discovery… Impalavis Attenborough “We show that the lack of teeth may not have been as unique in early Cretaceous enantiornithines as previously thought,” the researchers said.

The specific name is Impalavis Attenborough Attenborough’s strange bird, after the naturalist Sir David Attenborough.

Sir David Attenborough said: “It is a great honor to have your name attached to a fossil, especially one as spectacular and important as this one.”

“It seems the history of birds is more complicated than we thought.”

“All birds are dinosaurs, but not all dinosaurs fall into the special type of dinosaur known as birds. All squares are rectangles, but not all rectangles are squares. Is the same.”

“The newly explained Impalavis Attenborough Since it’s a bird, it’s also a dinosaur.”

a paper description Impalavis Attenborough Published in an online journal Cretaceous research.

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Wang Xiaoli other. 2024. The first edentulous enantiornithines from the Early Cretaceous Jehol ornithians (Birds: Ornithorax). Cretaceous research 159: 105867; doi: 10.1016/j.cretres.2024.105867

Source: www.sci.news

Cretaceous Dinosaurs with Armored Bodies had Two Cheek Horns

A new genus and species of ankylosaurid dinosaur have been identified from two specimens discovered in southeastern China.

type specimen of Datai Inliangis Rebuilt on site. The head, neck, and thorax of the specimen were discovered and extracted from a single block. Image credit: Xing other., doi: 10.18435/vamp29396.

named Datai Inliangisthe newly discovered dinosaur species roamed the Earth during the Late Cretaceous period, about 96 million to 90 million years ago.

ancient beast was a member strongosaursa group of club-tailed armored dinosaurs that reached a peak of diversity in the latest Cretaceous period.

“Ankylosaurids are iconic armored dinosaurs that characterized the terrestrial vertebrate fauna of Asia and Laramidia (western North America) during the Late Cretaceous period,” said a paleontologist from the China University of Geosciences. Rida Singh And my colleagues.

“The earliest members of this clade are known from the Early Late Cretaceous of Asia, but there is little consensus on how they relate to anatomically derived and chronologically younger forms. are not obtained.”

“In southeastern China, Cretaceous red sand beds extend into a basin from Zhejiang to Guangdong.”

“However, horizons corresponding to the early Late Cretaceous remain poorly sampled.”

Two well-preserved immature skeletons Datai Inliangis It was collected from the Zhoutian Formation in southeastern China.

The specimens were found combined, with one head placed on top of the other, representing slightly different stages of the ontogeny of the skeleton.

“This is the first definitive vertebrate skeleton, let alone an armored dinosaur skeleton, excavated from the Ganzhou Formation,” the paleontologists said.

According to the authors: Datai Inliangis It is characterized by having two cheekbones/square zygomatic angle.

“The primary horn develops in the posteroventral horn of the skull and projects posterolaterally,” the researchers explained.

“There is a small attached horn just in front of this that hides the jaw joint when viewed from the side.”

“Morphologically, it is intermediate to older Asian ankylosaurids (e.g. crichton pelta and Giyumperta) and derived post-Cenomanian ankylosaurines (e.g. pinacosaurus),” they added.

“Phylogenetic analyzes broadly support this assessment.”

“The new species will either be placed in the Asian ankylosaurine subfamily, which is close to the lineage of the derived taxon, or it will form a sister lineage.” pinacosaurus

“Based on these insights, Datai This genus represents an important addition to the Early Late Cretaceous vertebrate fauna of southeastern China and highlights the region's future potential for a better understanding of the origins and early evolution of ankylosaurids. ”

of discovery is reported in Vertebrate anatomy, morphology, and paleontology.

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L. Shin other. 2024. A new armored dinosaur with double cheek horns that lived in the early Late Cretaceous of southeastern China. Vertebrate anatomy, morphology, and paleontology 11; doi: 10.18435/vamp29396

Source: www.sci.news

Argentina Unearths New Species of Titanosaurus from Cretaceous Era

A genus and species of sauropod, a titanosaur mimicking rebachisaurid, measuring over 15 meters (50 feet) in length, has been unearthed in Patagonia, Argentina.



rebuilding the life of Inawentu Osratus. Image credit: Gabriel Rio.

The newly discovered dinosaur roamed the Earth during the late Cretaceous period, about 86 million years ago.

dubbing Inawentu Osratusthe animals were of the following types: titanosaurusa diverse group of long-necked sauropods that lived from the Late Jurassic period (163.5 million to 145 million years ago) to the end of the Cretaceous period (145 million to 66 million years ago).

They are known for their large body size, long necks, and wide stance, and include species ranging from the largest known land vertebrates to “dwarfs” as large as elephants. Some species had osteoderm (armor plate).

“During the late Mesozoic Era, sauropod dinosaurs constituted the main herbivores in all terrestrial ecosystems of polar Gondwana,” said paleontologist Leonardo Filippi of Argentina's Municipal Museum of Urquiza and his colleagues.

“Quadrupedal locomotion and a gravitational posture, a proportionately small cranio-body ratio, and a common bow plan consisting of a series of elongated necks and tails made sauropods capable of large size, locomotion, defense, physiology, and feeding. They have evolved a variety of notable adaptations related to food and behavior.”

“They represented, in terms of diversity and abundance, the major medium- to large-sized herbivore component of the fauna in most of these southern landmass.”

partially completed specimen Inawentu Osratus It was recovered from fluvial deposits at the La Invernada archaeological site, part of the Bajo de la Carpa Formation in the Neuquen Basin of Patagonia, Argentina.

“The recovered human bones were found interlocked within a horizon of massive reddish solidified mudstone covered by a thin layer of sand (30 cm thick) associated with flood deposits of the river bank. ' explained the researchers.

Inawentu Osratus It shows remarkable convergent properties of the skull anatomy. rebatisauridae sauropodaccording to the author.

Inawentu Osratus “It belongs to the square-jawed titanosaur clade and was restricted to the final stages of the Late Cretaceous of South America,” the researchers said.

“The discovery of new materials and different datasets providing new morphological information allows us to provide better support in future phylogenies confirming the existence of this square-jawed titanosaur clade. Become.”

Inawentu Osratus And perhaps other members of this clade have obvious nutritional adaptations seen in preceding rebatisaurid sauropods, such as broad snouts and relatively short necks. ”

“In this connection, a series of shortened cervix Inawentu Osratus This may be consistent with low browsing feed behavior. ”

“This could have paleoecological implications, such as a zoological alternation in the Gondwanan ecosystem since the Turonian period or a low-browsing diet in two distinct lineages of sauropod dinosaurs.”

team's findings It was published in the magazine Cretaceous research.

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Leonardo S. Filippi other. 2024. Rebachysaurid-mimic titanosaurs and evidence of faunal disturbance events in southwestern Gondwana during the Late Cretaceous. Cretaceous research 154: 105754; doi: 10.1016/j.cretres.2023.105754

Source: www.sci.news