T. Rex not as smart as previously claimed

Dinosaurs were as smart as reptiles but not as intelligent as monkeys, as former research suggests.

An international team of palaeontologists, behavioural scientists and neurologists have re-examined brain size and structure in dinosaurs and concluded they behaved more like crocodiles and lizards.

In a study published last year, it was claimed that dinosaurs like T. rex had an exceptionally high number of neurons and were substantially more intelligent than assumed. It was claimed that these high neuron counts could directly inform on intelligence, metabolism and life history, and that T. rex was rather monkey-like in some of its habits. Cultural transmission of knowledge as well as tool use were cited as examples of cognitive traits that it might have possessed.

However the new study, published today in The Anatomical Record, involving the University of Bristol's Hady George, Dr Darren Naish (University of Southampton) and led by Dr Kai Caspar (Heinrich Heine University) with Dr Cristian Gutierrez-Ibanez (University of Alberta) and Dr Grant Hurlburt (Royal Ontario Museum) takes a closer look at techniques used to predict both brain size and neuron numbers in dinosaur brains. The team found that previous assumptions about brain size in dinosaurs, and the number of neurons their brains contained, were unreliable.

The research follows decades of analysis in which palaeontologists and biologists have examined dinosaur brain size and anatomy, and used these data to infer behaviour and lifestyle. Information on dinosaur brains comes from mineral infillings of the brain cavity, termed endocasts, as well as the shapes of the cavities themselves.

The team found that their brain size had been overestimated -- especially that of the forebrain -- and thus neuron counts as well. In addition, they show that neuron count estimates are not a reliable guide to intelligence.

To reliably reconstruct the biology of long-extinct species, the team argues, researchers should look at multiple lines of evidence, including skeletal anatomy, bone histology, the behaviour of living relatives, and trace fossils. "Determining the intelligence of dinosaurs and other extinct animals is best done using many lines of evidence ranging from gross anatomy to fossil footprints instead of relying on neuron number estimates alone," explained Hady from Bristol's School of Earth Sciences.

Dr Kai Caspar explained: "We argue that it's not good practice to predict intelligence in extinct species when neuron counts reconstructed from endocasts are all we have to go on."

"Neuron counts are not good predictors of cognitive performance, and using them to predict intelligence in long-extinct species can lead to highly misleading interpretations," added Dr Ornella Bertrand (Institut Català de Paleontologia Miquel Crusafont).

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Mystery solved: The oldest fossil reptile from the alps is an historical forgery

A 280-million-year-old fossil that has baffled researchers for decades has been shown to be, in part, a forgery following new examination of the remnants.

The discovery has led the team led by Dr Valentina Rossi of University College Cork, Ireland (UCC) to urge caution in how the fossil is used in future research.

Tridentinosaurus antiquus was discovered in the Italian alps in 1931 and was thought to be an important specimen for understanding early reptile evolution.

Its body outline, appearing dark against the surrounding rock, was initially interpreted as preserved soft tissues.

This led to its classification as a member of the reptile group Protorosauria.

However, this new research, published in the scientific journal Palaeontology, reveals that the fossil renowned for its remarkable preservation is mostly just black paint on a carved lizard-shaped rock surface.

The purported fossilised skin had been celebrated in articles and books but never studied in detail.

The somewhat strange preservation of the fossil had left many experts uncertain about what group of reptiles this strange lizard-like animal belonged to and more generally its geological history.

Dr Rossi, of UCC's School of Biological, Earth and Environmental Sciences, said:

"Fossil soft tissues are rare, but when found in a fossil they can reveal important biological information, for instance, the external colouration, internal anatomy and physiology.

"The answer to all our questions was right in front of us, we had to study this fossil specimen in details to reveal its secrets -- even those that perhaps we did not want to know."

The microscopic analysis showed that the texture and composition of the material did not match that of genuine fossilised soft tissues.

Preliminary investigation using UV photography revealed that the entirety of the specimen was treated with some sort of coating material.

Coating fossils with varnishes and/or lacquers was the norm in the past and sometimes is still necessary to preserve a fossil specimen in museum cabinets and exhibits.

The team was hoping that beneath the coating layer, the original soft tissues were still in good condition to extract meaningful palaeobiological information.

The findings indicate that the body outline of Tridentinosaurus antiquus was artificially created, likely to enhance the appearance of the fossil.

This deception misled previous researchers, and now caution is being urged when using this specimen in future studies.

The team behind this research includes contributors based in Italy at the University of Padua, Museum of Nature South Tyrol, and the Museo delle Scienze in Trento.

Co-author Prof Evelyn Kustatscher, coordinator of the project "Living with the supervolcano," funded by the Autonomous Province of Bolzano said:

"The peculiar preservation of Tridentinosaurus had puzzled experts for decades. Now, it all makes sense. What it was described as carbonized skin, is just paint."

However all not all is lost, and the fossil is not a complete fake.

The bones of the hindlimbs, in particular, the femurs seem genuine, although poorly preserved.

Moreover, the new analyses have shown the presence of tiny bony scales called osteoderms -- like the scales of crocodiles -- on what perhaps was the back of the animal.

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A large predator from the Pyrenees

A fossilized lower jaw has led an international team of palaeontologists, headed by Bastien Mennecart from the Natural History Museum Basel, to discover a new species of predator that once lived in Europe. These large predators belong to a group of carnivores colloquially known as "bear dogs." They could weigh around 320 kilograms, appeared 36 million years ago before becoming extinct around 7.5 million years ago.

Palaeontologist Bastien Mennecart and his research group precisely described the fossilized lower jaw of a carnivore and discovered that it must be a specimen from a new species. The jawbone comes from 12.8 to 12 million-year-old marine deposits that were examined in the small community of Sallespisse in the Pyrénées-Atlantiques department of south western France.

The teeth of time

The jawbone was striking because of its teeth. Unlike the familiar amphicyonidae specimens, this animal has a unique fourth lower premolar. This tooth is particularly important for determining species and genera. Correspondingly, the lower jaw examined probably represents a new genus. It is called Tartarocyon. This name comes from Tartaro, a large, powerful, one-eyed giant from Basque mythology. The legend of Tartaro is also known in Béarn, the region where the lower jaw was found. Floréal Solé, a specialist in carnivorous mammals, Jean-François Lesport and Antoine Heitz from the Natural History Museum Basel chose the name of the new genus.

Dog-like predator

The fossilized lower jaw can be classified as belonging to predators that resembled a cross between a bear and a large dog, known as "bear dogs." Their scientific name is "Amphicyonidae." They belong to a group of carnivores such as dogs, cats, bears, seals and badgers. These predators were a widespread part of the European fauna of the Miocene (23 to 5.3 million years ago). They were very species-rich and diverse, weighing between 9 kg and 320 kg. Tarataroyon is estimated at 200 kg. The last European Amphicyonidae disappeared during the late Miocene 7.5 million years ago.

Key contemporary witnesses

Discoveries of fossilized terrestrial vertebrates that lived on the northern edge of the Pyrenees 13 to 11 million years ago are very rare. The discovery and description of the lower jaw is even more significant. That is because it offers the opportunity to explore the development of European "bear dogs" against the background of known environmental events at this time.

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Europe's largest land predator unearthed on the Isle of Wight

Research led by palaeontologists at the University of Southampton has identified the remains of one of Europe's largest ever land-based hunters: a dinosaur that measured over 10m long and lived around 125 million years ago.

Several prehistoric bones, uncovered on the Isle of Wight, on the south coast of England, and housed at Dinosaur Isle Museum in Sandown, belonged to a type of two-legged, crocodile-faced predatory dinosaur known as spinosaurids. Dubbed the 'White Rock spinosaurid' -- after the geological layer in which it was found -- it was a predator of impressive proportions.

"This was a huge animal, exceeding 10 m in length and probably several tonnes in weight. Judging from some of the dimensions, it appears to represent one of the largest predatory dinosaur ever found in Europe -- maybe even the biggest yet known," said PhD student Chris Barker, who led the study. "It's a shame it's only known from a small amount of material, but these are enough to show it was an immense creature."

The discovery follows previous work on spinosaurids by the University of Southampton team, which published a study on the discovery of two new species in 2021.

The bones of the 'White Rock spinosaurid', which include huge pelvic and tail vertebrae, amongst other pieces, were discovered near Compton Chine, on the southwest coast of the Isle of Wight. The Cretaceous rocks are famous for their dinosaurs, but little appreciated is the fact that the Island's fossil record preserves dinosaurs from more than one section of history -- and some of those sections, even today, are poorly known.

"Unusually, this specimen eroded out of the Vectis Formation, which is notoriously poor in dinosaur fossils," said corresponding author Dr Neil Gostling, who teaches evolution and palaeobiology at the University of Southampton. "It's likely to be the youngest spinosaur material yet known from the UK."

The 125 million year old Vectis Formation preserves the beginning of a period of rising sea levels, where the 'White Rock spinosaurid' stalked lagoonal waters and sandflats in search of food.

"Because it's only known from fragments at the moment, we haven't given it a formal scientific name" said co-author Darren Naish. He added: "We hope that additional remains will turn up in time.

"This new animal bolsters our previous argument -- published last year -- that spinosaurid dinosaurs originated and diversified in western Europe before becoming more widespread."

Marks on the bone also showed how, even after death, the body of this giant probably supported a range of scavengers and decomposers.

"Most of these amazing fossils were found by Nick Chase, one of Britain's most skilled dinosaur hunters, who sadly died just before the Covid epidemic," said co-author Jeremy Lockwood, a PhD student at the University of Portsmouth and Natural History Museum. "I was searching for remains of this dinosaur with Nick and found a lump of pelvis with tunnels bored into it, each about the size of my index finger. We think they were caused by bone eating larvae of a type of scavenging beetle. It's an interesting thought that this giant killer wound up becoming a meal for a host of insects."

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Pterosaur discovery solves ancient feather mystery

An international team of palaeontologists has discovered remarkable new evidence that pterosaurs, the flying relatives of dinosaurs, were able to control the colour of their feathers using melanin pigments.

The study, published in the journal Nature, was led by University College Cork (UCC) palaeontologists Dr Aude Cincotta and Prof. Maria McNamara and Dr Pascal Godefroit from the Royal Belgian Institute of Natural Sciences, with an international team of scientists from Brazil and Belgium.

The new study is based on analyses of a new 115 million year old fossilized headcrest of the pterosaur Tupandactylus imperator from north-eastern Brazil. Pterosaurs lived side by side with dinosaurs, 230 to 66 million years ago.

This species of pterosaur is famous for its bizarre huge headcrest. The team discovered that the bottom of the crest had a fuzzy rim of feathers, with short wiry hair-like feathers and fluffy branched feathers.

"We didn't expect to see this at all," said Dr Cincotta. "For decades palaeontologists have argued about whether pterosaurs had feathers. The feathers in our specimen close off that debate for good as they are very clearly branched all the way along their length, just like birds today."

The team then studied the feathers with high-powered electron microscopes and found preserved melanosomes -- granules of the pigment melanin. Unexpectedly, the new study shows that the melanosomes in different feather types have different shapes.

"In birds today, feather colour is strongly linked to melanosome shape." said Prof. McNamara. "Since the pterosaur feather types had different melanosome shapes, these animals must have had the genetic machinery to control the colours of their feathers. This feature is essential for colour patterning and shows that coloration was a critical feature of even the very earliest feathers."

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