These are the tusk-toothed heterodontosaurids, spike-thumbed iguanodonts, shovel-beaked hadrosaurs, spike-tailed stegosaurs, heavily-armored ankylosaurs, dome-headed pachycephalosaurs, and multi-horned ceratopsids. But, contrary to their timid image, such dinosaurs frequently fought members of their own species. Raymond M. Farke lays out three lines of inference that clue paleontologists in to dinosaur combat. First, and most flimsy, is analogy to modern animals.
Since antelope and other bovids sometimes lock horns in tussles, Farke points out, paleontologists thought that ceratopsid dinosaurs such as Triceratops did the same.
Bovids have sinuses in their skulls. Researchers thought that the spaces acted as shock absorbers for cranial clashes, and therefore similar structures in dinosaur skulls were believed to perform the same function. As Farke found out through some of his own research, however, the sinuses of bovids have little to do with combat, and so dinosaur sinuses probably were not shock-absorbers, either.
Not to mention that dinosaur horns and bovid horns are different in shape, size, orientation, and number. A Styracosaurus is not a sable antelope. Biomechanical studies get a little closer to what was actually possible for dinosaur fights. By simulating head-butting, spike-swinging, and other combat behaviors, paleontologists can estimate whether the animals were actually capable of inflicting, and surviving, the trauma seen in movies and richly-illustrated books.
The bipdeal pachycephalosaurs are immediately recognizable for their tonsure-style skulls — bald, often-rounded tops with a ring of spikes of varying sizes around the back. Researchers have since tried to model how pachycephalosaurs such as Stegoceras and Pachycephalosaurus would have coped from head-on collisions, but without much agreement.
Where some researchers have concluded that the reinforced skulls of these dinosaurs were well-suited to butting, other scientists have proposed that such cracks on the noggin would have been extremely traumatic, if not fatal. For decades, there was no independent line of evidence for dome-smacking dinosaurs. The closest paleontologists could get was modeling the fights. Then, in , paleontologists Joseph Peterson and Christopher Vittore published a study focused on lesions pocking a Pachycephalosaurus skull.
Along with further instances Peterson published with other authors the following year , such injuries could have been caused by head-butting. Was head-butting the cause of the skull damage? And what was once perceived as an injury could turn out to be caused by something else. Paleontologists have found multiple cases of healed, inflamed vertebrae near the end of some sauropod tails, often in Late Jurassic dinosaurs such as Apatosaurus and Diplodocus.
Researchers previously attributed these injuries to sneaky carnivores nibbling at the tips of sauropod tails or the painful price of trying to mate, but the whip-like anatomy of these tails tips brings up another possibility. Perhaps sauropods with these long, delicate strings of tail bones — belonging to a group appropriately-named the Flagellicaudata — really did swing their tails like whips, occasionally breaking their own bones in the process.
Modeling what sauropods could have done may be the closest we can get. A biomechanics study by Nathan Myhrvold and paleontologist Philip Currie suggested that Apatosaurus and other sauropods really could crack their tails like whips. But rather than being a weapon to strike with, the authors proposed, the tail whips would have been better for making loud cracking sounds.
Still, this would be just one sort of weapon in the sauropod arsenal. Other sauropods, such as Shunosaurus , had tail clubs that they could have come in handy for predator defense, fights with each other, or as a flag for species recognition.
If sauropods used their tails for self-defense, they probably swung them at the carnivorous theropods that nipped at their flanks. Not all theropods were dedicated carnivores — many appear to have evolved omniovorous or even herbivorous lifestyles — but the best evidence for combat comes from the dagger-toothed members of the group.
These predators often fought with their mouths. Lesions and healed wounds on Mesozoic skulls show that allosaurs, tyrannosaurs, and other theropods shared a common mode of attack. They bit each other on the face. There may even be evidence of a fatal tyrannosaur duel. The jaw shows no sign of healing, meaning it happened around the time of death or afterward.
This could have been a case of scavenging, or, as Bell and Currie point out, it might be a rare example of a fatal fight between two tyrannosaurs.
The number of shed teeth and partial Deinonychus skeletons found in a single Montana quarry led paleontologist John Ostrom to speculate that these dinosaurs might have been hunting their prey — a dinosaur named Tenontosaurus found in the same place — as a group.
But a reassessment of the site by researchers Brian Roach and Daniel Brinkman forwarded an alternative scenario. Instead of working together, perhaps Deinonychus fought each other as they competed for access to meat. Shell tools were recovered from an Italian cave that show Neanderthals combed beaches and dove in the ocean to retrieve a specific type of clam shell to use as tools.
A closer look at the Heslington brain, which is considered to be Britain's oldest brain and belonged to a man who lived 2, years ago.
Amazingly, the soft tissue was not artificially preserved. Researchers from Russia's RAS Institute of Archeology excavated the burial sites of four women, who were buried with battle equipment in southwestern Russia and believed to be Amazon warrior women.
The oldest woman found in the graves bore a unique, rare ceremonial headdress. Teen Tyrannosaurus rex were fleet-footed with knife-like teeth, serving as mid-sized carnivores before they grew into giant bone-crushing adults.
A Homo erectus skull cap discovered in Central Java, Indonesia reveals how long they lived and when the first human species to walk upright died out. This is an artistic reconstruction of Lola, a young girl who lived 5, years ago. Part of the scene depicted in the world's oldest cave art, which shows half-animal, half-human hybrids hunting pigs and buffalo.
An ancient Egyptian head cone was first found with the remains of a young woman buried in one of Amarna's graves. A lice-like insect was trapped in amber crawling and munching on a dinosaur feather. Newly discovered penguin species Kupoupou stilwelli lived after the dinosaurs went extinct and acts as a missing link between giant extinct penguins and the modern penguins in Antarctica today. This illustration compares the jaws and teeth of two predatory dinosaurs, Allosaurus left and Majungasaurus right.
This is an artist's illustration of Najash rionegrina in the dunes of the Kokorkom desert that extended across Northern Patagonia during the Late Cretaceous period. The snake is coiled around with its hindlimbs on top of the remains of a jaw bone from a small charcharodontosaurid dinosaur.
University of South Carolina archaelogist Christopher Moore second from right and colleagues collect core samples from White Pond near Elgin, South Carolina, to look for evidence of an impact from an asteroid or comet that may have caused the extinction of large ice-age animals such as sabre-tooth cats and giant sloths and mastodons.
Core samples from White Pond near Elgin, South Carolina, show evidence of platinum spikes and soot indicative of an impact from an asteroid or comet. The Sosnogorsk lagoon as it likely appeared million years ago just before a deadly storm, according to an artist's rendering.
The newly discovered tetrapod can be seen in the left side of the image below the surface. Bronze goods recovered from a river in northern Germany indicate an ancient toolkit of a Bronze Age warrior. Mold pigs are a newly discovered family, genus and species of microinvertebrates that lived 30 million years ago. Ferrodraco lentoni was a pterosaur, or "flying lizard," that lived among dinosaurs 96 million years ago. The fossil was found in Australia. These Late Bronze Age feeding vessels were likely used for infants drinking animal milk.
This is the first depiction of what mysterious ancient humans called Denisovans, a sister group to Neanderthals, looked like. This image shows a young female Denisovan, reconstructed based on DNA methylation maps. The art was created by Maayan Harel. Researchers found a fossil of one of the oldest bird species in New Zealand. While its descendants were giant seafaring birds, this smaller ancestor likely flew over shorter ranges.
A painting shows the new species of giant salamander called Andrias sligoi, the largest amphibian in the world. After her discovery in , Victoria's million-year-old, fossilized skeleton was restored bone by bone.
She's the second most complete T. An artist's illustration shows how different an ancient "short-faced" kangaroo called Simosthenurus occidentalis looked, as opposed to modern kangaroos. Its skull more closely resembles a koala. An artist's illustration of Cryodrakon boreas, one of the largest flying animals that ever lived during the Cretaceous period.
Although researchers don't know the color of Cryodrakon's plumage, the colors shown here honor Canada, where the fossil was found. A graphic thermal image of a T.
A complete skull belong to an early human ancestor has been recovered in Ethiopia. A composite of the 3. His identity has been the subject of great debate for years. Vertebrae fossils of a previously undiscovered type of stegosaurus were found in Morocco. Researchers say they represent the oldest stegosaurus found. The La Chapelle-aux-Saints Neanderthal skull shows signs of external auditory exostoses, known as "surfer's ear" growths, in the left canal. The Fincha Habera rock shelter in the Ethiopian Bale Mountains served as a residence for prehistoric hunter-gatherers.
The world's largest parrot, Heracles inexpectatus, lived 19 million years ago in New Zealand. It was over 3 feet tall and weighed more than 15 pounds. About 67 million years ago, two iconic dinosaurs, a Triceratops horridus and a Tyrannosaurus rex, died and were quickly buried together side by side in a single grave. And both of them bear battle scars. It's the kind of showdown scientists have speculated about for years, but it has only ever appeared in "Jurassic Park" games -- until now.
The impressively complete skeletons of these " dueling dinosaurs " will go on display and be studied at the North Carolina Museum of Natural Sciences in , the museum announced Tuesday.
The museum is located in downtown Raleigh. New fossil discovery suggests dinosaurs traveled across oceans. The fossil of the Triceratops was first discovered as it eroded out of sedimentary rock from the Hell Creek Formation.
This rock formation, which dates to The remains of a Tyrannosaurus rex were also found slightly overlapping with the Triceratops. Both were extracted from the rock formation, encased in plaster and safely stored until they could be studied.
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