This giant lizard sowed terror in the ocean 66 million years ago!

The T-rex, a predator… slow The T-rex, which according to legend was a top predator, was actually quite slow. He was only running at 30 kilometers per hour. Not bad for a 6 ton animal but also not spectacular for a so called “king of animal life”. Osborn, the author of these words, and Brown had in fact eagerly put on a “paleo-show” to varnish their reputations. To the dump of the beast, it could still snatch up to 35 kilos of fresh meat in one bite of the jaw! © Courtesy of Vlad Konstantinov

A third of dinosaurs never existed Of all the known species of dinosaurs, one out of three would be an illusion… This is the conclusion reached by the famous paleontologist John Jack Horner and his colleague Mark B. Goodwin. Marked morphological differences between juveniles and adults would have misled paleontologists. Some species would therefore not be distinct. © Courtesy of Caren Carr, http://www.karencarr.com

Dinosaurs had feathers! The discovery of a dinosaur fossil in China suggests that dinosaurs looked more like large birds than towering, scaly-skinned lizards. This fossil, that of a bipedal carnivorous dinosaur, 128 million years old and 90 centimeters high, provides the first proof of the existence of dinosaurs covered with real feathers, like those of modern birds. This is the first non-flying dinosaur fossil found with such feathers. At the same time, he suggests that the evolution towards modern feathers began before the emergence of birds. Photo: Archeopteryx. © Courtesy of Jon Hughes, www.pixel-shack.com

Dinosaurs could swim Dinosaurs could swim. At least, it’s likely. The discovery was made by examining layers of sandstone sediments, deposited about 125 million years ago at the bottom of a lake located in what is now the Cameros Basin, in Spain. The layer therefore dates from the Lower Cretaceous and it contains a track 15 meters long. There are a series of S-shaped prints, about 15 centimeters wide and 50 long, which resemble scratches. In total, there are six pairs of such prints. The allosaurus represented here may have left these traces at the bottom of the lake. © Courtesy of Jon Hughes, www.pixel-shack.com

Dinosaurs had cancers Researchers have analyzed, using a portable X-ray device, 10,000 dinosaur vertebrae from more than 700 museum specimens in North America. Only one group would have suffered from tumor: the hadrosaurs or duck-billed dinosaurs. The team found 29 tumors in the bones from 97 individuals from this group of herbivores from the Cretaceous period. The most common tumors were hemangiomas, benign tumors of blood vessels, present in 10% of humans. The edmontosaurus, which measured 3.5 meters, was the only species in which a malignant tumor was found. © DP

Dinosaurs were bigger than expected By using a “cartilage correction factor”, scientists were able to show that some dinosaurs like the tyrannosaurus would have been only a few centimeters taller, while the triceratops and the brachiosaurus would have gained at least 10% in size, or at least 30 centimeters for a brachiosaurus of 13 meters. This has a direct impact on the weight of the dinosaurs, which has therefore also been underestimated. © Marmelad, Tedd Marshall, www.marshalls-art.com, CC by-sa 2.5

Crocodiles like Supercroc ate ​​dinosaurs A hundred million years ago, where the Sahara is today, lived a world of crocodiles. Some were modest in size but the largest, Sarcosuchus imperator, reached about 12 meters and must have weighed 8 tons. The Anglo-Saxons like to call it “Supercroc”. This giant is not unknown, the French Philippe Taquet discovered it in 1964. The discovery of the team led by Paul Sereno, who works for National Geographic, and Hans Larsson, of McGill University in Montreal, n so it’s no surprise. But she’s not the only one. Since 2000, these paleontologists have been exploring the Sahara in several places, notably in Niger and Morocco. In these sites, which a hundred million years ago lay at the heart of a single continent, Gondwana, in the process of breaking up, the team unearthed five other species of crocodilians, three of which were unknown to the science. To continue the habit of nicknames, the discoverers christened them “Boarcroc”, “Ratcroc”, “Dogcroc”, “Duckcroc” and “Pancakecroc”. Their discoveries are the subject of a scientific publication in the journal Zookeys but also of a report on the National Geographic television channel, entitled When Crocs Ate Dinosaurs (“When crocodiles ate dinosaurs”, broadcast on November 21, 2009 ). Photo: Paul Sereno with his Saharan crocodiles. Supercroc serves as an armrest. Boarcroc (Croc Sanglier) is top right, Pancakecroc (Croc Galette) bottom right. The small heads, bottom left, are respectively Ratcroc, Dogcroc and Duckcroc. © Mike Hettwer and National Geographic

The disappearance of the dinosaurs made the mammals grow After the great Permian-Triassic extinction (about 252 million years ago) and within a few tens of millions of years, the first dinosaurs and the first mammals appeared on Earth. The dinosaurs will quickly impose themselves and block both the diversification and the growth in size of mammals. It is not until asteroid 298 Baptistina causes their mass extinction that an evolutionary radiative burst will occur in mammals. A group of paleontologists, biologists (evolutionary specialists) and macroecologists led by Felisa Smith (from the University of New Mexico) has just confirmed that from the KT crisis (between Cretaceous and Tertiary, or Cenozoic, 65 million years ago) occurs on all continents an increase in the size of new species of mammals. It would therefore be thanks to the disappearance of the dinosaurs that giants like the baluchithère were able to set foot on the ground of the Blue Planet. © Courtesy of Karen Carr, http://www.karencarr.com

Dinosaurs: the bigger they are, the hotter they are! Were the dinosaurs “warm-blooded” or “cold-blooded”? According to Jamie Gillooly and his colleagues at the University of Gainesville, Florida, who publish the results of their work in Plos Biology, it all depended on their size! It appears from their study that the larger the dinosaurs were, the higher their temperature was. The reason ? The ratio between the surface of contact with the outside and the volume of their body decreased, which allowed them to better “store” the heat. A phenomenon that grew when the weight of a dinosaur exceeded 600 kilograms. Thus, Jamie Gillooly and his colleagues at the University of Gainesville have established that the smallest species had a temperature of around 25°C, therefore substantially close to that of their environment, while that of the body of the 13-ton Brontosaurus reached 41°C! Pictured: argentinosaurus. © Courtesy of Jon Hughes, www.pixel-shack.com

The T-rex had a bird’s brain! It is still unclear whether Tyrannosaurus rex, often abbreviated as T-rex, were formidable predators or simple scavengers. Paleontologists, on the other hand, are sure that they must have had, indeed, “bird brains” and not only because birds are the last living dinosaurs and close cousins ​​of T-rex. Indeed, internal casts have long revealed that the brains of these formidable animals that lived in Cretaceous North America were indeed tiny, and not just when compared to their body size. The image is from one of the 3D videos of the T-rex skull. In colors, we see the different cavities. © Ohio University College of Osteopathic Medicine