Gastornis parisiensis measured on average 1.75 metres (5.7 ft) tall, but large individuals grew up to 2 metres (6.6 ft) tall. The Gastornis had a remarkably huge beak with a slightly hooked top, which was taken as evidence suggesting that it was carnivorous. Gastornis had large powerful legs, with large, taloned feet, which also were considered in support of the theory that it was a predator…
Paraphysornis is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or “terror birds” within the subfamily Brontornithinaethat lived inBrazil. Its length was about 2 meter and the skull had a length of 60 centimeter. The only known species is Paraphysornis brasiliensis. It lived 23 million years ago.
The origins of winged flight is a hotly debated topic in paleontology. A study published last year in Science suggests that wings and feathers may have evolved in dinosaurs earlier than previously thought. When researchers took a closer look at several fossil specimens of Ornithomimus edmontonicus, they found winglike forelimbs and hundreds of traces of filaments suggestive of feathers. Ornithomimus belongs to a group of dinosaurs that appears in the fossil record millions of years before maniraptorans, the group of feathered dinosaurs that survives today as birds, the findings hint at even earlier evolutionary origins of wings and feathers.
O. edmontonicuswas no flier, however. The researchers estimate it weighed 150 kilograms (330 pounds), so it’s wings more likely served some other function, perhaps in courtship or brooding.
Image: Julius Csotonyi (above)/Royal Tyrrell Museum (below)
Meet the oldest boneheaded dinosaur in North America, and possibly in the world. Acrotholus audeti was identified from two solid bone skull caps found in southern Alberta, Canada. The bony domes are 10 cms (4 in) thick. The researchers who describe the new species this week in Nature Communications say their find hints at the possibility of more discoveries of small, plant-eating dinosaurs to come.
Killer Cave Lured Ancient Carnivores to Their Death
by Tia Ghose
A cavern in Spain may have lured ancient carnivores to their deaths by offering the promise of food and water, new research suggests.
The new study, published today (May 1) in the journal PLOS ONE, may explain how the carcasses of several carnivore species, including saber-toothed cats and “bear dogs,” wound up in an underground cavern millions of years ago.
“Only the carnivores were daring enough to enter,” said study co-author M. Soledad Domingo, a paleontologist at the University of Michigan. “But they were unable to make their way out.”…
(images:1 - illustration of sabertooths with rhino in ancient cave by Mauricio Anton; 2 - photo of Sabertooth skull by Soledad Domingo; 3 - illustration of cave history by Anton, Domingo, Sanchez; 4 - fossil skeleton of ancient “Bear-Dog” by ghedoghedo | Wikimedia)
Dinosaurs have changed quite a bit since I was a kid. Tails have been lifted, spines adjusted, skulls switched around, wrists repositioned, and feathery body coverings added, just to start. But some dinosaurs have changed more than others.
The tottering, lizard-skinned Tyrannosaurus rex of my youth shuffled awkwardly after whatever was slow enough to catch, while the modern visions of the carnivore depict a fluffy tyrant with a spine held parallel to the ground and a respectable 10-15 mile per hour run. T. rex almost three decades after I first met the predator is a very different animal. But the great armor-plated dinosaur Stegosaurus hasn’t undergone the same degree of sweeping alterations. Not quite.
Contrary to what I learned as a kid, Stegosaurusdid not have a butt brain, nor did the dinosaur rely on the sun to warm up. And despite the variety of Stegosaurus renditions out there, lovely skeletons and evidence gleaned from them have shown that the famous dinosaur had plates arranged in a single alternating row and a thagomizer bearing four spikes. Stegosaurus was still among the oddest of all dinosaurs, but the image of the hefty herbivore as a stooped, moronic pile of ectothermic armor has been extinct for years now…
I don’t know why a raven is like a writing desk, but I do know that Microraptor was like a cat. The feathery little dinosaur was cute and glossy, but those adorable features were offset by the carnivore’s excessive pointiness. Even though the non-avian dinosaur was about the size of a raven, and even had feathers with an iridescent corvid sheen, Microraptor still bore pointed teeth, grasping hand claws, and the classic deinonychosaur switchblade talons on each foot. All of this made Microraptor a cuddly-looking little cutter, much like a cat. And the dinosaur shared something else with felines – a fondness for fish.
Since the time the dinosaur was named in 2000, paleontologists have discovered multiple specimens of Microraptor in the 120 million year old lake deposits of China. Many of these are not only articulated, but fossilized to such a fine degree that the petrified remains of their feathers remain intact. This hi-def preservation also safeguarded tatters of Microraptor meals. One Microraptor individual, described two years ago, had feasted on an early bird shortly before perishing in a case of non-avian dinosaur eats avian dinosaur. But a Microraptor known as QM V1002 enjoyed a different last meal.
Fossilized in the position of QM V1002′s stomach, paleontologist Lida Xing and colleagues explain in a new Evolution paper, are the scraps of bony fish. A small mass of fin rays, vertebrae, and other piscine tidbits are tucked between the dinosaur’s ribs, some of which had been etched by digestive fluids when the Microraptor was still alive. The question is whether this Microraptor actually caught fish or just happened along some convenient snacks thrown up onto the lakeshore…
Steve White: “Not strictly speaking sharks, Echinochimaera(left) and Belantsea were both very strange Chondrichthyans from the famous Bear Gulch formation (a limestone layer laid down in the Mississippian epoch of the Carboniferous period, about 318 mya) in Montana. Would love to do a book of all those weirdos.”
Wiwaxia was one of the bizarre animals found in the 505-million-year-old Burgess Shale Formation of British Columbia, Canada.
Squashed flat in the rocks, these 5cm (2”) spiny creatures were difficult to analyze and reconstruct, and what exactly they were is still being debated. For many years they were tentatively considered to be distant relatives of polychaete or annelid worms, but more recent studies and better microscopic imaging techniques have found a primitive radula-like structure in their mouths — suggesting that they might actually be closer related to molluscs.
The armour coat of scale-like sclerites and the long asymmetrical rows of spines were probably a defense against predators. I’ve given it a splash of some sea-slug warning colors here just for fun.
Fossilized guts reveal that Microraptor — a four-winged, flying dinosaur — had an unusual taste for fish. Located near the fossil’s ribs, a mass of fish bones bearing the mark of strong digestive acids suggests the crow-sized reptile’s prey veered from the arboreal to the aquatic.
“There are only two other good examples of dinosaurs with a taste for sushi: the giant, crocodile-like spinosaurs and the tiny compsognathids,” said Scott Persons, from the University of Alberta. “So, no. Fish are not usually considered as staples of a dino’s diet.”
Previous analyses of Microraptor specimens pointed toward prey retrieved from trees: small mammals and birds. But a new analysis, reported Apr. 19 by Persons and colleagues in the journal Evolution, suggests the dinosaur feasted on fish as well. The team based its conclusions on specimen QM V1002, retrieved from northeastern China in an area thought to have been a forested, freshwater lake environment 120 million years ago. Nearly complete, though with a badly crushed skull, the fossil bears traces of the long, dark feathers that have come to distinguish Microraptor. Among the preserved bones and feathers is a lump of bony fish bits that includes fin rays, ribs, vertebrae, and bits of acid-etched fish skull…
By studying fossilized embryonic femur bones at different stages of development, scientists can learn how Lufengosaurus grew up to be a giant.
Nearly 200 million years ago, some of the earliest dinosaurs on Earth laid their eggs in modern Yunnan Province in southern China, only to have one nest after another destroyed by floods. Today, the remains of those lost eggs—and the embryonic dinosaurs that they contained—are helping scientists understand how their relatives grew up to be giants…
Everybody knows “Lucy.” For nearly four decades, this famous partial skeleton of Australopithecus afarensis, dated to 3.2 million years ago, has been an ambassador for our prehistoric past, and her species has stood as the most likely immediate ancestor of our own genus-Homo.
But in a spate of new studies, paleoanthropologist Lee Berger, of the University of the Witwatersrand, and a team of collaborators have put forward a controversial claim that another hominin-Australopithecus sediba-might be even closer to the origin of our lineage, possibly bumping Lucy from the critical evolutionary junction she has occupied for so long.
Berger and colleagues named Australopithecus sediba in 2010. The 1.98-million-year-old hominin, known from partial skeletons of an adult female and a juvenile male, along with an isolated tibia, was discovered two years earlier at the South African cave site of Malapa…
Apr. 10, 2013— The great age of the embryos is unusual because almost all known dinosaur embryos are from the Cretaceous Period. The Cretaceous ended some 125 million years after the bones at the Lufeng site were buried and fossilized.
Led by University of Toronto Mississauga paleontologist Robert Reisz, an international team of scientists from Canada, Taiwan, the People’s Republic of China, Australia, and Germany excavated and analyzed over 200 bones from individuals at different stages of embryonic development.
“We are opening a new window into the lives of dinosaurs,” says Reisz. “This is the first time we’ve been able to track the growth of embryonic dinosaurs as they developed. Our findings will have a major impact on our understanding of the biology of these animals.”
The bones represent about 20 embryonic individuals of the long-necked sauropodomorph Lufengosaurus, the most common dinosaur in the region during the Early Jurassic period. An adult Lufengosaurus was approximately eight metres long…