It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Monday, April 20, 2026
Stone age population collapse revealed by DNA study in France
The research, published in Nature Ecology & Evolution, is based on genetic analyses of 132 individuals buried in a large megalithic tomb near Bury, about 50 kilometres north of Paris. The site was used during two distinct periods separated by a population decline around 3000 BC.
Researchers found that the two groups buried before and after the decline were not genetically related, pointing to a major population turnover.
“We see a clear genetic break between the two periods,” said Frederik Valeur Seersholm, assistant professor at the Globe Institute at the University of Copenhagen and one of the lead authors of the study.
“The earlier group resembles Stone Age farming populations from northern France and Germany, while the later group shows strong genetic links to southern France and the Iberian Peninsula.”
The findings suggest a sharp reduction in the local population followed by the arrival of new groups from the south.
Disease and high mortality
Using a DNA method that analyses all genetic material preserved in bone, the researchers detected traces of ancient pathogens, including the plague bacterium Yersinia pestis and louse-bourne relapsing fever caused by Borrelia recurrentis.
“We can confirm that plague was present, but the evidence does not support it as the sole cause of the population collapse,” said Martin Sikora, associate professor at the University of Copenhagen and senior author of the study. “The decline was likely driven by a combination of disease, environmental stress and other disruptive events.”
Archaeological analysis of the skeletal remains shows unusually high mortality in the earlier burial phase, particularly among children and young people.
“The demographic pattern is a strong indicator of crisis,” said Laure Salanova, research director at France’s National Centre for Scientific Research (CNRS).
Shift in social organisation
The DNA data also reaffirm a marked change in social structure.
In the earlier phase, multiple generations from the same extended families were buried together, suggesting tightly knit communities. In the later phase, burials were more selective and dominated by a single male lineage, pointing to a different form of organisation.
“This indicates that the population change was accompanied by a shift in how society was structured,” Seersholm said.
A wider European pattern
The findings add to growing evidence that the so-called Neolithic decline affected much of northern and western Europe, not only Scandinavia and northern Germany.
The study also offers a possible explanation for why the construction of megalithic tombs and other large stone monuments ended across Europe around the same time.
“We now see that end of these monumental constructions coincides with the disappearance of the population that built them,” Seersholm said.
With their massive bodies, long necks and tails, and tiny heads, long-necked dinosaurs (sauropods) embody the image of a typical dinosaur for many people. Sauropods include the largest known land animals of all time, with body lengths of up to 40 meters; the best-known examples are Diplodocus and Brachiosaurus.
The new long-necked dinosaur from southern Argentina is not quite as large: the researchers estimate the length of Bicharracosaurus dionidei to be around 20 meters. Parts of its spine were recovered, including over 30 neck, back, and tail vertebrae, several ribs, and a fragment of the pelvic bone. The structure of the bones indicates that the remains belong to an adult animal that lived on the southern continent of Gondwana around 155 million years ago. The fossil is interesting to researchers in many ways: it combines a mix of characteristics from both brachiosaurids and diplodocids. For instance, some skeletal parts of Bicharracosaurus show similarities to the African Giraffatitan, a brachiosaurid from Tanzania. Other features, particularly those of its dorsal vertebrae, resemble Diplodocus and its closest relatives from North America.
“Our phylogenetic analyses of the skeleton indicate that Bicharracosaurus dionidei was related to the Brachiosauridae, which would make it the first Brachiosauridae from the Jurassic of South America,” says LMU doctoral student Alexandra Reutter, the study’s first author. The paleontologist analyzed the remains of the new dinosaur as part of her doctoral thesis.
“Our knowledge of the evolution of sauropods from the Late Jurassic has so far been based almost entirely on numerous fossil findings from North America and other sites in the Northern Hemisphere. For a long time, there was only a single significant site on the southern continents, in Tanzania. The fossil site in the Argentine province of Chubut, from which Bicharracosaurus dionidei originates, provides us with important comparative material, allowing us to continuously supplement and reevaluate our understanding of the evolutionary history of these animals, particularly in the Southern Hemisphere,” says leader of the study and dinosaur expert Prof. Oliver Rauhut of the Bavarian State Collections of Natural History (SNSB).
The first remains of Bicharracosaurus dionidei were discovered by shepherd Dionide Mesa on his farm, the researchers chose the species name of the new dinosaur in his honor. The genus name is derived from “bicharraco,” colloquial Spanish for “big animal”. The fossil comes from the Cañadón Calcáreo rock formation in the Patagonian province of Chubut and is housed at the Museo Paleontológico Egidio Feruglio in Trelew, Argentina.
Bicharracosaurus dionidei, gen. et sp. nov., a new macronarian (Dinosauria, Sauropoda) from the Late Jurassic Cañadón Calcáreo Formation of Argentina and the problematic early evolution of macronarians
Article Publication Date
16-Apr-2026
Fossil extraction ofBicharracosaurus dionidei.
Credit
Pablo Puerta
Bicharracosaurus vertebrae being prepared at the Egidio Feruglio Paleontological Museum in Trelew, Argentina.
Credit
Amalia Villafañe
Alexandra Reutter with remains ofBicharracosaurus dionideiat the Egidio Feruglio Paleontological Museum in Trelew, Argentina.
Credit
Amalia Villafañe
Reconstruction of Bicharracosaurus dionidei
Credit
Felipe Cutro-Lev
Giant Aussie dinosaur was well equipped to nibble on tasty bush tucker
In a surprising new study, Australia’s most famous plant-eating dinosaur has been described as a “picky eater with a nose for good food” when it roamed across the continent around 96 million years ago.
After examining different parts of the skull from new bones of the large-bodied ornithopodMuttaburrasaurus langdoni, fossil experts from across Australia and the US have released several new insights in a journal article published in PeerJ.
Lead author Dr Matthew Herne, from The University of New England, says that the discovery re-defines several assumptions made about the bumpy-nosed species, which is the fossil emblem of Queensland.
The first astonishing discovery was that Muttaburrasaurus had teeth at the tip of its snout.
“This was unexpected, because the beak (front part of the snout) of Muttaburrasaurus was thought to be toothless like many other well-known plant-eating species such as Iguanodon from Europe and the ‘duck-billed’ Hadrosaurs, mostly found in the Northern Hemisphere.
“But ornithischian dinosaurs of this size normally have beak-like snouts without teeth, with a good example of this being Triceratops,” says Dr Herne.
Therefore, the beak of this Australian dinosaur wasn’t toothless and most likely a pickier eater. With its narrow toothy beak, Muttaburrasaurus would have browed for particular leaves and seeds and possibly even invertebrates for variety in their diet.
This also means that Muttaburrasaurus evolved from an earlier offshoot of the ornithopod dinosaurs from Camptosaurus and Iguanodon, when the earlier forms of the small-bodied ornithischians all had toothed beaks.
This new finding can help place Muttaburrasaurus more accurately on the dinosaur tree of life.
The new bones, unearthed in the same historic site in central Queensland as the original skeleton named after the township of Muttaburra, also reveal some tantalising clues about the behaviour and life of the animals.
Coauthor Professor Vera Weisbecker, from Flinders University, says the findings were made by extracting the brain imprint on the skull and the inner ears.
“We realised that its inner ear was more like dinosaurs that walked on two legs, like Tyrannosaurus rex, than others that spent more time on all fours,” she says.
“So it’s possible that Muttaburrasaurus was a large herbivore walking and running on its hind legs when needed and used its front arms for support to crop food closer to the ground.”
The team also found that the characteristic ‘bulbous’ shape of Muttaburrasaurus’ nose is comprised of entirely new bones that are not found in other dinosaurs.
Dr Herne says finding the new bones was exciting because they revealed two large complex air chambers above the main inhaled airflow which would have slowed down air as it breathed in.
“So we suspect that they indicate a very acute sense of smell, perhaps to help the animal find food, detect predators or assist in directional navigation,” explains UNE Adjunct Research Fellow in Vertebrate Palaeontology Dr Herne, who is also affiliated with Queensland Museum and Australian Age of Dinosaurs Museum of Natural History in Queensland.
He says this feature of the nose also matches their very large olfactory bulbs – “among the largest of any dinosaur” – which are the parts of the brain where smell is processed.
Another coauthor Dr Joseph Bevitt, from the Australian Nuclear Science and Technology Organisation (ANSTO), says the use of advanced CT scanning, neutron scattering and synchrotron technologies provided detailed 3D digital models of the jaws and teeth.
These remarkable new insights into the skull of Muttaburrasaurus provided other intriguing findings, including:
THE DISCOVERY that premaxillary bones in the Muttaburrasaurus muzzle evolved to exclude the nasal bones from bordering the nostrils. This feature was only previously known in the hollow crested lambeosaurine hadrosaurs from the Northern Hemisphere, indicating possible independent convergent evolution between northern and southern hemisphere dinosaurs.
EYE SOCKET measurements and fleshed-out restoration of the head show that its vision was typical for a large herbivore, with a wide field of view to the sides but with little ability to see in front of itself. The wide panoramic vista experienced by Muttaburrasaurus could have helped it avoid predators or track its herd.
GEOLOGICAL evidence suggests that Muttaburrasaurus lived close to the inland Eromanga Sea that invaded much of central Australia from 140 million to 90 million years ago. The CT examination of nasal cavities suggest Muttaburrasaurus could have used specialised nasal salt glands to remove excess salt from coastal plants and possibly crustaceans it consumed at the end of the inland sea.
RATHER THAN shear or cutting, the newly acquired CT imagery of cheek teeth show that Muttaburrasaurus would have ground its food, like other ornithopods and in a similar way to horses, cows and kangaroos.
Researchers add there is still not enough evidence to tell whether Muttaburrasaurus lived in herds like many other large ornithischians such as the hadrosaurs or Triceratops.
Acknowledgements: This work was supported by a UNE Postdoctoral fellowship to Matthew C Herne and assistance was provided by the Barcaldine Regional Council, Australian Age of Dinosaurs Museum and multiple research partners.
Queensland fossil expert Dr Matthew Herne at the Muttaburrasaurus site.
Credit
Photo by Chris Rohan
Muttaburrasaurus langdoni, left, illustrated in Queensland Australia, around 96 million years ago. Other dinosaurs include a Megaraptoran carnivore, small ornithopods and enantiornithine birds. Illustration courtesy James Kuether.
Cranial anatomy, palaeoneurology, palaeobiology and stratigraphic age of the large-bodied ornithopod, Muttaburrasaurus langdoni Bartholomai and Molnar, 1981, from the mid-Cretaceous of Australia
Article Publication Date
13-Apr-2026
Student identifies new meat-eating dinosaur three times older than T. rex
Credit: Photo by Spencer Coppage for Virginia Tech.
“You want to stick your finger in a dinosaur brain?” asked Simba Srivastava.
Surrounded by cabinets full of ancient bones in the paleobiology lab, the Virginia Tech undergraduate student held out a lumpy, pockmarked fossil.
“This is a uniquely sucky specimen,” said Srivastava. “It's so bad. Like, if you saw a human skull in this way, you'd throw up.”
Nevertheless, the senior geosciences major spent two years unscrambling the ancient creature and determining its place in the story of evolution. His findings, which were published today in Papers in Palaeontology,shed light on how dinosaurs dominated the Jurassic period.
This is the type of work a long-tenured curator or a late-stage professor would do, but geobiologists Sterling Nesbitt and Michelle Stocker tapped Srivastava when he was a first-year student.
“We want undergraduate researchers to experience the whole paleontological research process at Virginia Tech,” said Nesbitt. “Simba grabbed the project by the reins.”
Dino domination
The mangled skull was uncovered twice: In 1982, a crew from the Carnegie Museum of Natural History unearthed it from New Mexico’s Ghost Ranch. Thirty-some years later, Nesbitt dug it out of a drawer and eventually brought it back to Blacksburg. Using computed tomography scanning data, Srivastava isolated the specimen digitally and 3D printed a reconstruction.
The skull belonged to a species of meat-eating dinosaur that’s more than three times as old as Tyrannosaurus Rex.
These creatures lived at the end of the Triassic period, which is about 252 million to 201 million years ago. Back then, dinosaurs weren’t the all-powerful apex predators portrayed by Hollywood. They were vying for resources against the forerunners of crocodiles and mammals.
But that all changed drastically when an extinction seemingly wiped out most of the competition. With that, the Triassic ended, and dinosaurs came into their power.
“Dinosaurs go from being co-stars to the headliner,” Srivastava said.
Clues about how dinosaurs evolved and spread in the succeeding Jurassic period lie buried in the rocks, but well-preserved fossils from the end of the Triassic are rare.
In fact, Srivastava’s squished specimen is the only one of its kind anyone has found so far.
The skull shows that the species had massive cheekbones, a wide braincase, and probably a short, deep snout. It was the first time these characteristics had been seen in early dinosaurs, indicating that they were constantly evolving, according to the study.
Murder muppet’s last stand
The name Srivastava picked for the new species reflects its bizarre proportions and unfortunate condition.
“We landed on Ptychotherates bucculentus, which means‘folded hunter with full cheeks’ in Latin,” said Srivastava. “One paleo-artist said that it looked like a murder muppet.”
After two years of deep research, the Virginia Tech team was able to determine that the skull belonged to one of the last surviving members of one of the earliest-evolving families of carnivorousdinosaurs called Herrerasauria.
Thanks to this fossil, the group made another, somewhat surprising discovery.
Ptychotherates was found in rocks that may date to right before the great extinction at the end of the Triassic period — and no other members of their family was ever seen again, possibly suggesting that this dinosaur group went extinct as a result of that mass extinction.
“This forces us to reconsider the impact of the end-Triassic extinction as something that wiped out not just the competitors to dinosaurs, but some long-standing dinosaur lineages themselves,” Srivastava said.
And finally, because no herrerasaurians have been found anywhere else this late in the Triassic, the area that is today the American Southwest may have been where they survived the longest and made their last stand.
Srivastava’s folded hunter is their only spokesperson.
“This specimen, it fits in my hands, but it is the only proof that any of these dinosaurs lived this long, lived in these latitudes, the only proof that they evolved to have this skull shape,” said Srivastava. “All these billions of individuals that existed through time are spoken for by this one specimen.”
