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Torosaurus

Saturday, December 10, 2016

Torosaurus by atrox1 on DeviantArt

Torosaurus is a genus of herbivorous ceratopsid dinosaur that lived during the late Maastrichtian stage of the Cretaceous period, between 68 and 66 million years ago. Its name means “perforated lizard” in reference to the large openings in its frill. Fossils have been discovered across the Western Interior of North America, from Saskatchewan to southern Texas.

Torosaurus by PrehistoricWildlife.com

Torosaurus possessed one of the largest skulls of any known land animal. The frilled skull reached up to 2.77 metres (9.1 ft) in length. From head to tail, Torosaurus is thought to have measured about 7.6 to 9 m (24.9 to 29.5 ft) long and weighed four to six tonnes. Torosaurus is distinguished from the contemporary Triceratops by an elongate frill with large openings (fenestrae), long squamosal bones of the frill with a trough on their upper surface, and the presence of five or more pairs of hornlets (epoccipitals) on the back of the frill. Torosaurus also lacked the long nose horn seen in Triceratops prorsus, and instead resembled the earlier and more basal Triceratops horridus in having a short nose horn. Three species have been named, Torosaurus latusT. gladius and T. utahensisT. gladius is no longer considered a valid species, however.

Recently the validity of Torosaurus has been disputed. A 2010 study of fossil bone histology combined with an investigation of frill shape concluded that Torosaurus probably represented the mature form of Triceratops, with the bones of typical Triceratops specimens still immature and showing signs of a first development of distinct Torosaurus frill holes. During maturation, the skull frill would have been greatly lengthened and holes would have appeared in it. In 2011, 2012 and 2013, however, studies of external features of known specimens have claimed that morphological differences between the two genera preclude their synonymy. The main problems are a lack of good transitional forms, the apparent existence of authentic Torosaurus subadults, different skull proportions independent of maturation and the assertion that hole formation at an adult stage is not part of a normal ceratopsian maturation sequence.

Scanella & Horner saw Nedoceratops as an ontogenetic transitional form between Triceratops and Torosaurus

All ceratopsians, including Torosaurus and Triceratops, were herbivores. The jaws contained rows of teeth that slid past each other as the jaws closed, creating a shearing action that would have allowed Torosaurus to process tough vegetation, perhaps the ferns that formed much of the ground cover. A slightly longer, narrower snout in Torosaurus than in Triceratops suggests that they might have had different feeding preferences.

Tuojiangosaurus

Saturday, December 10, 2016

Tuojiangosaurus

Tuojiangosaurus (meaning “Tuo River lizard”) is a genus of herbivorous stegosaurid dinosaur from the Late Jurassic Period, recovered from the Upper Shaximiao Formation of what is now Sichuan Province in China.

Tuojiangosaurus has the typical narrow and low head, bulky body, and low teeth of other stegosaurids. The limbs, especially the arms, are rather short. There are at least twenty-five dentary teeth. The teeth have a thick base, cingulum, merging at the inside into a triangular vertical median ridge. The dorsal vertebrae have tall neural arches. The shoulderblade has a rectangular acromion.

Tuojiangosaurus multispinus by Pachyornis

Tuojiangosaurus was by Dong placed in Stegosauridae in 1977, more precisely in the Stegosaurinae. In 2004, a cladistic analysis by Galton recovered Tuojiangosaurus in a rather derived position, as a sister species of Chialingosaurus. An analysis by Susannah Maidment in 2006, confirmed its status as a member of the Stegosauridae.

Like KentrosaurusTuojiangosaurus had two rows of plates along the spine, which became taller over the hip region. Those at the neck and front trunk were rounded or pear-shaped; the plates at the rear back became more triangular and pointed. All plates have a thickened central section, as if they were modified spikes. Dong estimated there were about seventeen pairs of plates and spikes. Tuojiangosaurus had at least two outward-pointing, rather robust, spikes on each side of the end of the tail, angled at approximately 45 degrees to the vertical. In stegosaurids, this spike arrangement has become affectionately known as the “thagomizer”. Dong thought it were possible that there were four pairs of spikes. Paul, based on “Chungkingosaurus sp. 3″ specimen CV 00208, interpreted the thagomizer as a “pin-cushion array”, with two vertical pairs of thick spikes and a third pair of narrow spikes pointing to behind.

Reconstructed skeleton of Tuojiangosaurus

Another two stegosaurs-Chialingosaurus and Chungkingosaurus-lived in China alongside Tuojiangosaurus in the late Jurassic. Both of these were smaller than Tuojiangosaurus, and they may have coexisted by dividing up the plants they ate based on the height at which they fed. Alternatively, the smaller stegosaurs may have inhabited more enclosed forests, which would have protected them from predators, while the larger Tuojiangosaurus lived in a more open environment, protected by its size.

In 1974, during construction of the Wujiaba dam in Zigong, Sichuan, the remains of stegosaurians were found.

The type and only species of TuojiangosaurusTuojiangosaurus multispinus, was named and described in 1977 (exactly a hundred years after the naming of Stegosaurus by Othniel Charles Marsh) by Dong Zhiming, Zhou Shiwu, Li Xuanmin and Chang Yijong. The generic name is derived from the River (jiang) Tuo. The specific name is derived from Latin multus, “many”, and spina, “spine”.

Yangchuanosaurus attacking Tuojiangosaurus. Author: Foolp

The holotype, CV 209, was found in a layer of the Upper Shaximiao Formation, dating from the Oxfordian-Kimmeridgian. It consists of a rather complete skeleton that however lacks parts of the skull., lower jaws, tail and limbs. In 1977, it represented the most complete stegosaurian skeleton found in Asia. The paratype was specimen CV 210, a sacrum. Subsequently, more material has been referred, including juveniles. This complemented the holotype with elements of the skull, especially the braincase, and the lower jaws.

A mounted skeleton of Tuojiangosaurus multispinus is on display at the Municipal Museum of Chongqing. In addition, a mounted cast is on display at the Natural History Museum, in London.

Troodon

Saturday, December 10, 2016

Troodon by Taena Doman

Troodon is a dubious genus of relatively small, bird-like dinosaurs known definitively from the Campanian age of the Cretaceous period (about 77 mya). It includes at least one species, Troodon formosus, known from Montana. Discovered in October 1855, T. formosus was among the first dinosaurs found in North America, although it was thought to be a lizard until 1877. Several well-known troodontid specimens from the Dinosaur Park Formation in Alberta were once believed to be members of this genus. However, recent analyses in 2017 have found the genus to be undiagnostic and referred some of these specimens to the genus Stenonychosaurus (long believed to be synonymous with Troodon) and others to the newly created genus Latenivenatrix.

Troodon by Prehistoric-Wildlife.com

The genus name is Greek for "wounding tooth", referring to the teeth, which were different from those of most other theropods known at the time of their discovery. The teeth bear prominent, apically oriented serrations. These "wounding" serrations, however, are morphometrically more similar to those of herbivorous reptiles, and suggest a possibly omnivorous diet.

The name was originally spelled Troödon (with a diaeresis) by Joseph Leidy in 1856, which was officially amended to its current status by Sauvage in 1876. The type specimen of Troodon has caused problems with classification, as the entire genus is based only on a single tooth from the Judith River Formation. Troodon has historically been a highly unstable classification and has been the subject of numerous conflicting synonymies with similar theropod specimens.

The Troodon tooth was originally classified as a "lacertilian" (lizard) by Leidy, but reassigned as a megalosaurid dinosaur by Nopcsa in 1901 (Megalosauridae having historically been a wastebin taxon for most carnivorous dinosaurs). In 1924, Gilmore suggested that the tooth belonged to the herbivorous pachycephalosaur Stegoceras, and that Stegoceras was in fact a junior synonym of Troodon (the similarity of troodontid teeth to those of herbivorous dinosaurs continues to lead many paleontologists to believe that these animals were omnivores). The classification of Troodon as a pachycephalosaur was followed for many years, during which the family Pachycephalosauridae was known as Troodontidae. In 1945, Charles Mortram Sternberg rejected the possibility that Troodon was a pachycephalosaur due to its stronger similarity to the teeth of other carnivorous dinosaurs. With Troodon now classified as a theropod, the family Troodontidae could no longer be used for the dome-headed dinosaurs, so Sternberg named a new family for them, Pachycephalosauridae.

The first specimens assigned to Troodon that were not teeth were both found by Sternberg in the early 1930s, in the Dinosaur Park Formation of Alberta. The first was named Stenonychosaurus inequalis by Sternberg in 1932, based on a foot, fragments of a hand, and some tail vertebrae. A remarkable feature of these remains was the enlarged claw on the second toe, which is now recognized as characteristic of early paravians. Sternberg initially classified Stenonychosaurus as a member of the family Coeluridae. The second, a partial lower jaw bone, was described by Gilmore (1932) as a new species of lizard which he named Polyodontosaurus grandis. Later, in 1951, Sternberg recognized P. grandis as a possible synonym of Troodon, and speculated that since Stenonychosaurus had a "very peculiar pes" and Troodon "equally unusual teeth", they may be closely related. Unfortunately, no comparable specimens were available at that time to test the idea. In a recent revision of the material by van der Reest & Currie, Polyodontosaurus was determined to be a nomen dubium, not fit fot synonymy with other taxa.

Skeletal restoration of T. inequalis by Scott Hartman

Troodon is considered to be one of the most derived members of its family. Along with Zanabazar, Saurornithoides and Talos it forms a clade of specialized troodontids.

One study was based on multiple Troodon teeth that have been collected from Late Cretaceous deposits from northern Alaska. These teeth are much larger than those collected from more southern sites, providing evidence that northern Alaskan populations of Troodon grew to larger average body size. This study also provides an analysis of the proportions and wear patterns of a large sample of Troodon teeth. It proposes that the wear patterns of all Troodon teeth suggest a diet of soft foods - inconsistent with bone chewing, invertebrate exoskeletons, or tough plant items. This study hypothesizes a diet primarily consisting of meat.

Troodon Skull

The type specimen of Troodon formosus was found in the Judith River Formation of Montana. The rocks of the Judith River Formation are equivalent in age with the Oldman Formation of Alberta, which has been dated to between 77.5 and 76.5 million years ago.

Source: www.wikipedia.org / www.natgeo.com

Velociraptor

Saturday, December 10, 2016

Restored V. mongoliensis skeleton in Japan

Velociraptor (meaning “swift seizer” in Latin) is a genus of dromaeosaurid theropod dinosaur that lived approximately 75 to 71 million years ago during the later part of the Cretaceous period. Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis; fossils of this species have been discovered in Mongolia. A second species, V. osmolskae, was named in 2008 for skull material from Inner Mongolia, China.

When first described in 1924, Velociraptor was placed in the family Megalosauridae, as was the case with most carnivorous dinosaurs at the time (Megalosauridae, like Megalosaurus, functioned as a sort of ‘wastebin’ taxon, where many unrelated species were grouped together). As dinosaur discoveries multiplied, Velociraptor was later recognized as a dromaeosaurid. All dromaeosaurids have also been referred to the family Archaeopterygidae by at least one author (which would, in effect, make Velociraptor a flightless bird).

Size of Velociraptor (2) compared with other dromaeosaurs

Smaller than other dromaeosaurids like Deinonychus and AchillobatorVelociraptor nevertheless shared many of the same anatomical features. It was a bipedal, feathered carnivore with a long tail and an enlarged sickle-shaped claw on each hindfoot, which is thought to have been used to tackle prey. Velociraptor can be distinguished from other dromaeosaurids by its long and low skull, with an upturned snout.

Velociraptor (commonly shortened to “raptor”) is one of the dinosaur genera most familiar to the general public due to its prominent role in the Jurassic Park motion picture series. In real life, however, Velociraptor was roughly the size of a turkey, considerably smaller than the approximately 2 m (7 ft) tall 80 kg (180 lb) reptiles seen in the films. Today, Velociraptor is well known to paleontologists, with over a dozen described fossil skeletons, the most of any dromaeosaurid. One particularly famous specimen preserves a Velociraptor locked in combat with a Protoceratops.

The type skull of V. mongoliensis on display at the American Museum of Natural History by Smokeybjb

Most important of all is the question of their size. The Velociraptor of the late Cretaceous was barely longer than 3 feet (1 m); in the movie, however, it was shown to be the size of a large adult human-and it looked all the more ferocious as a result.

It is interesting to note that while Jurassic Park was still being filmed, the remains of Utahraptor -a previously unknown dromaeosaurid, which was about the same size as those “faked” for the movie, were found in Wyoming.

Mounted V. mongoliensis cast at Wyoming Dinosaur Center. Photo by Ben Townsend

Fossils of dromaeosaurids more primitive than Velociraptor are known to have had feathers covering their bodies and fully developed feathered wings. The fact that the ancestors of Velociraptor were feathered and possibly capable of flight had long suggested to paleontologists that Velociraptor bore feathers as well, since even flightless birds today retain most of their feathers. In September 2007, researchers found quill knobs on the forearm of a Velociraptor found in Mongolia. These bumps on bird wing bones show where feathers anchor, and their presence on Velociraptor indicate it too had feathers.

Wuerhosaurus

Saturday, December 10, 2016

Wuerhosaurus

Wuerhosaurus is a genus of stegosaurid dinosaur from the Early Cretaceous Period of China and Mongolia. As such, it was one of the last genera of stegosaurians known to have existed, since most others lived in the late Jurassic.

Wuerhosaurus size. Wiki

Wuerhosaurus, one of the last of the stegosaurs, lived about 20 million years after the time, in the late Jurassic, when these plant-eaters were in their prime. It is not clear why the stegosaurs died out, but most scientists believe that their demise was related to the rise of the other main group of armored dinosaurs-the ankylosaurs. This assumes that stegosaurs and ankylosaurs shared the same niche in the environment, and that the emerging ankylosaurs developed some kind of advantage over the more primitive stegosaurs. Just what that advantage could have been, however, we can only guess at.

Wuerhosaurus homheni is the type species, described by Dong Zhiming in 1973 from the Tugulu Group in Xinjiang, western China. The generic name is derived from the city of Wuerho.

The remains consisted of the holotype IVPP V.4006, a skull-less fragmentary skeleton, and the paratype IVPP V4007, three vertebrae from the tail of a second individual.

A smaller species from the Ejinhoro Formation in the Ordos Basin in Inner Mongolia, W. ordosensis, was formalized by the same researcher in 1993. It is based on specimen IVPP V6877, a fragmentary skeleton lacking the skull. It was found in 1988. A third species, W. mongoliensis, is based on dorsal and caudal vertebrae as well as a pair of pubes.

Susannah Maidment and colleagues proposed in 2008 that Wuerhosaurus should be considered a junior synonym of Stegosaurus, with type species W. homheni as Stegosaurus homheni and second species W. ordosensis regarded as dubious. This opinion has been contested, however.

The type species, W. homheni, is known from the Tugulu Group, while W. ordosensis was found in the Ejinhoro Formation.

Wuerhosaurus homheni was probably a broad-bodied animal. Gregory S. Paul in 2010 estimated the length at 7 metres (23 ft) and the weight at four tonnes. Only a few scattered bones have been found, making a full restoration difficult. Its dorsal plates were at first thought to have been much rounder or flatter than other stegosaurids, but Maidment established this was an illusion caused by breakage: their actual form is unknown. W. homheni had a pelvis of which the front of the ilia strongly flared outwards indicating a very broad belly. The neural spines on the tail base were exceptionally tall.

W. ordosensis was estimated by Paul to have been 5 metres (16.5 feet) long and weigh 1.2 tonnes. It too has a broad pelvis but the neural spines are shorter. The neck seems to have been relatively long.

Wuerhosaurus was lower to the ground than most other stegosaurids; scientists believe that this was an adaptation to let it feed on low-growing vegetation. Wuerhosaurus, like other stegosaurids, perhaps had a thagomizer on the end of its tail, like that of Stegosaurus which featured four bony spikes that would most likely have been used for self-defense. A single spike was found but was seen by Dong as being positioned on the shoulder.

10 Awesome Facts About Utahraptor

Saturday, December 10, 2016

Pack of Utahraptors atacking an Iguanodon

During the Jurassic Park-crazed early ‘90s, Utahraptor became a media darling. Now, more than 20 years later, some great new finds just might push this predator back into the limelight.

1. IT WAS ONE OF THE WORLD’S LARGEST “RAPTORS.”

Scientists call VelociraptorMicroraptor, and their kin “dromaeosaurs” (the unofficial raptor nickname is way cooler, though). At around 18 feet long, Utahraptor could have easily been the biggest of the bunch. However, Asia’s impressive Achillobator giganticus might eventually give it a run for its money—if some more complete skeletons emerge.

2. WALKING WITH DINOSAURS (1999) PUT UTAHRAPTOR ON THE WRONG CONTINENT.

WALKING WITH DINOSAURS

During an epic scene from this now-classic miniseries, a Utahraptor pack goes Iguanodon hunting through Europe. As you’ve probably deduced, Utahraptor was originally found well within the U.S. (care to guess where?) and, so far, this animal has left no trace across the pond.

3. THE CARNIVORE WIELDED TERRIFYINGLY-HUGE TOE CLAWS.

Wikimedia Commons // CC BY-SA 3.0

To Hollywood, brandishing nasty, hook-like claws on each foot is basically the raison d’etre of any dromaeosaur. At their bony cores, Utahraptor’s were 9 inches long apiece, and the nails themselves were probably 15 inches!

4. IT WASN’T THE ONLY “RAPTOR” IN TOWN.

Wikimedia Commons // CC BY-SA 3.0

One hundred and twenty-six million years ago, Utahraptor coexisted with the coyote-sized dromaeosaur Yurgovuchia doellingi near what’s now Arches National Park.

5. PALEONTOLOGIST ROBERT BAKKER MADE A CLEVER UTAHRAPTORTHE STAR OF HIS FIRST NOVEL.

Ballista, via Wikimedia Commons // CC BY-SA 3.0

If you’re a self-respecting dino maniac, go check out Raptor Red. Robert Bakker, a fossil-hunting icon, felt that most storytellers unfairly typecast predators as bloodthirsty villains. To counter this, his novel follows an energetic Utahraptor and her family as they fight for survival in a harsh prehistoric wilderness.

6. UTAHRAPTOR IS PART OF AN INTERESTING EVOLUTIONARY TREND.

Matt Martyniuk, via Wikimedia Commons // CC BY-SA 3.0

As time went by, truly huge dromaeosaurs like Utahraptor and Achillobator fell out of fashion. As they disappeared, smaller relatives (like North America’s 11-foot Deinonychus) began arising until, by 75 million years ago, few “raptors” were much bigger than a modern turkey.

7. UTAHRAPTOR CRASHED THE PILOT EPISODE OF PRIMEVAL: NEW WORLD.

PRIMEVAL: NEW WORLD

The creators of this time-traveling drama gave their Utahraptor a fluffy, bird-like coat. While there’s no direct evidence for feathers in this particular genus, the dino’s celebrity cousin Velociraptor is known to have rocked sturdy ones upon its lower arms.

8. IT WAS ALMOST NAMED AFTER STEVEN SPIELBERG.

Nobu Tamura, via Wikimedia Commons // CC BY 2.5

Everything would have come together perfectly. Utahraptor fragments had previously been found in 1975, but the beast received neither a name nor any serious attention until better specimens were unearthed well over a decade later. By 1991, paleontologist James I. Kirkland had rounded up some amazing new material and decided to call this forgotten creature “Utahraptor.” However, he hadn’t yet assigned it a species name.

That’s when a golden business opportunity came a-knocking. The highly-anticipated Jurassic Park had already entered pre-production, so Kirkland contacted JP’s director and offered to dub his dino “Utahraptor spielbergi” in exchange for fieldwork funds. Regrettably, Kirkland’s plan bore no fruit, and the name U. ostrommaysorum was chosen instead. (C’mon, Spielberg: Whatever happened to “Spared no expense?”)

9. A UTAHRAPTOR GRAVEYARD AWAITS FURTHER STUDY.

To date, our understanding of Utahraptor has been woefully incomplete, since the dinosaur’s known from very few specimens. But that’s all about to change: A 16-foot adult, four adolescents, and a three-foot baby were recently found together in the Utah dirt. This haul includes Utahraptor bones we’ve never seen before, and the fact that so many were found in close proximity might even offer clues about dromaeosaur social lives. “We’re really going to have a different view of this guy,” says Kirkland, who’s been overseeing their excavation.

10. SEVERAL SKELETONS WERE TEMPORARILY LEFT IN A PARKING LOT.

Emily Willoughby via Wikimedia Commons // CC BY-SA 3.0

Last November, Kirkland’s new Utahraptor gang found itself stranded. After the rock slab which contained these skeletons was sealed in a protective plaster jacket and hauled to Salt Lake City, it was stored between vehicles in an outdoor parking lot until more suitable housing was located.

Article first appeared on www.NationalGeographic.com

20 Myths About Dinosaurs

Saturday, December 10, 2016

We love dinosaurs. As kids, we learned facts about them in science class, marveled at their skeletons in museums, and played out epic dino battles with our plastic toys. But how much of what we were taught about them is actually true? You might be shocked to know that a majority of what we learned about dinosaurs in our youth was actually not true at all.

Dinosaurs Roared Like Giant Lizard Lions

University of Texas at Austin-based paleontologist Julia Clarke has spent a lot of time studying whether or not dinosaurs could vocalize. Until 2013, when Clarke and her team discovered a nearly intact syrinx in a fossilized Late Cretaceous bird Vegavis iaai, an ancestor of ducks and geese, no dinosaur vocal box had ever been discovered.

Nearly all existing species with the ability to vocalize have a larynx, which is your standard vocal box. Birds have a syrinx, which is more complex than the larynx, and accounts for the unique noises our feathered friends make. The syrinx Clarke found is proof animals of the dinosaur-age were able to vocalize, though neither syrinx nor layrinx has ever been found with dinosaur remains.

Clarke and her team have developed a theory, by which they think “many dinosaurs did not have a syrinx but in fact vocalized in a manner more similar to that which we see in crocs… low-frequency booms, maybe using a resonating structure such as an inflated esophagus or something like that, and using the larynx, not a syrinx.”

Dinosaurs Were Green and Scaly

People imagine dinosaurs as green and scaly because we assume they must have looked like big modern reptiles like crocodiles or alligators. In actuality, they were probably brightly colored and, at least for part of their lives, covered in feathers.

Tyrannosaurus Rex’s Small Forearms Were Weak and Useless

You might have heard someone tell you that Tyrannosaurus rex’s relatively small forearms were useless appendages, but that probably wasn’t the case. The dinosaur was heavily muscled and could probably move in excess of 430 pounds with each of those arms.

Dinosaurs Were Cold Blooded

For decades scientists believed that dinosaurs were cold blooded like modern reptiles. But Australian scientists stated that if the dinosaurs did have cold blood they would not have had the muscular power to prey on other animals. As more evidence is found that shows that dinosaurs were fast-moving carnivores, it is more likely that they were warm blooded like their avian descendants.

Velociraptors Were Terrifying and Larger Than Humans

Most of us never heard of a Velociraptor before Jurassic Park, so those movies gave us the idea that they were scaly, human-sized predators that were incredibly smart… smart enough to open doors! The truth is that although they were vicious little things, they weren’t much bigger than a large dog and were likely covered in feathers. They looked more like a big, angry chicken than a giant, smooth lizard.

Dinosaurs Lived in a Tropical, Endless Summer

Every painting and museum display you see of dinosaurs shows them in a lush, tropical setting. And although many dinosaurs lived in such a setting, Late Cretaceous sites in the High Arctic lived in cool habitats that were dark for long stretches of the year. So, yes, you might have actually seen at T. rex tromping through the snow.

Anything Prehistoric and Reptilian Was a Dinosaur

A lot of people assume that any animal that is extinct and reptilian is a dinosaur, but that’s just not true. Dinosaurs were just one lineage within a group called archosaurs, which also includes pterosaurs and crocodiles. They all split from each other some 245 million years ago. Although they lived alongside dinosaurs, the long-necked, swimming plesiosaurs, flying pterosaurs and other giant reptiles were not dinosaurs.

Dinosaurs Were All Giant Animals

Dinosaurs came in all sizes, but the big ones captured our imagination most. Among the smallest dinosaurs were bird-sized forms such as the feathery Anchiornis and the tiny theropod Scansoriopteryx. Dinosaurs really existed like the ones the little girl fed in The Lost World: Jurassic Park.

Dinosaurs Died Out Because They Failed to Evolve

Let’s put this into perspective: Dinosaurs survived for 150 million years. Hominids have only been kicking around for six million years, while Homo sapiens has only been around for about 200,000 years. We have a long way to go before we last as long as the dinosaurs did, and we don’t know how we would adapt to an asteroid impact like the dinosaurs endured.

Dinosaurs Dragged Their Tails

A lot of older museum exhibits of dinosaurs assembled the bones so that the tails were dragging on the ground, like Godzilla. This is one myth the Jurassic Park movies helped dispel, because the tails were lifted off the ground and aided in balance. There is no evidence of “tail tracks” in fossils of dinosaur footprints.

Dinosaurs Are Extinct

There is ample evidence that points to birds evolving from dinosaurs–to the extent that some scientists would argue that birds ARE dinosaurs. The avian line of dinosaurs survived after the asteroid impact that wiped out the rest of the dinosaurs. Ostriches, chickens, pigeons, penguins, eagles and all the other birds are more closely related to dinosaurs than crocodiles, turtles, lizards and snakes.

Dinosaurs Terrorized Our Mammalian Ancestors

The mammals that existed during the reign of the dinosaurs were relatively small. So they must have fled in terror from these giant, prehistoric reptiles, right? Well, those ancient mammals ate dinosaurs, too. A specimen of Repenomamus—a 125-million-year-old mammal about the size of a raccoon—had baby dinosaurs preserved in its gut.

Dinosaurs Were the First Reptiles to Rule the Earth

Since a lot of people just assume that any ancient reptile is a dinosaur, then dinosaurs must have been the first reptiles to rule the Earth. Not true. The first reptiles evolved from their amphibian ancestors during the Carboniferous period some 300 million years ago. The first true dinosaurs didn’t appear until about 230 million years ago.

Dinosaurs Were All Equally Stupid

It’s true that the stegosaurus has a walnut-sized brain and that most herbivores were probably not much smarter than the plants they munched on. But meat eaters, like the Allosaurus, had larger brains and one theropod, Troodon, must have seemed like a genius compared to his peers.

An Asteroid Killed All the Dinosaurs Quickly

Although most scientists agree that a mile-wide meteor that crashed into the Yucatan Peninsula some 65.5 million years ago helped wipe out the dinosaurs, most people assume this happened fairly quickly. In actuality, it took a couple hundred thousand years after the impact for most of the dinosaurs to die off.

Giant Dinosaurs Had a Second Brain Near Their Butt

Some of us were taught that dinosaurs’ brains were so small that some of the larger ones needed a second brain at the tail end of their spines to coordinate their legs and tails. Now paleontologists agree that, like many vertebrates, dinosaurs had a slight expansion of the spinal cord in the vicinity of their limbs and not a second brain.

Dinosaurs Were Slow and Lumbering

Many movies and TV shows have depicted dinosaurs as slow, lumbering beasts due to the immense size of some of them. Most dinosaurs were probably as mobile as large, modern mammals. One study in 2000 of an exceptionally well-preserved hadrosaur fossil suggested that dinosaurs had powerful hearts more like those of birds or mammals than modern reptiles, so they had higher metabolisms and were more active.

Archaeopteryx Is the Link Between Dinosaurs and Birds

We used to hear that the Archaeopteryx was the link between dinosaurs and birds. We were told it was the first bird (“It had feathers!”). Well, now that we know that lots of dinosaurs like T. rex and Velociraptor had feathers, it’s suddenly not so special that Arcaheopteryx had feathers. In fact, it wasn’t the first “bird” at all. It was just another feathered dinosaur.

Humans and Dinosaurs Coexisted

The only time a human has every laid eyes on dinosaur was in a movie like Jurassic Park. Dinosaurs died out some 65 million years ago, while the fossils of our earliest human ancestors are only 6 million years old.

Related: Over 40% of Americans Believe Humans and Dinosaurs Shared the Planet

Dinosaurs Had Boring Sex Lives

Most of your childhood lessons on dinosaurs probably never leaned into their reproductive habits, and any mention of prehistoric hanky-panky likely covered the simple fact that they laid eggs. Turns out, though, that dinosaur courtship may have been an elaborate affair a lot like bird romance. Massive scrapes in Colorado sandstone suggest that dinos performed elaborate mating ritual displays in order to impress potential mates, with suitors basically dancing to woo partners.

Stop Making Fun of T-rex’s Small Arms

Saturday, December 10, 2016

Tyrannosaurus arm

T. rex: Bigger Than a Bus

At 40 feet long and 15 to 20 feet high, his “small” arms were pretty much bigger than your whole body.

Via nationalgeographic.com

T. rex: Able to Rip the Head off of a Triceratops

In order to get around that bulky “neck frill”, they just chomped down and used it to pull the ENTIRE Triceratops head CLEAN OFF and then feasted on the delicious neck meat.

Who would need arms for that anyway?

Via dailymail.co.uk

T. rex: Able to eat 1/4 Ton of Meat in ONE BITE

Speaking of feasting on the flesh of inferiors, T. rex could eat up to 500 pounds of meat in one tasty mouthful.

Need super long arms for that? I didn’t think so.

Via animals.nationalgeographic.com

T. rex: Killer Breath

Sure, he couldn’t reach to brush or pick any food out of his teeth, but you know what? That just made it a more efficient killing machine. Some experts believe the pieces of bacteria-infested meat lodged and rotting in its SIXTY teeth gave it a septic bite. If for some reason you were lucky enough to escape somehow after being nipped by the T. rex, you would still eventually probably die. Your normal sized arms wouldn’t have helped you one bit.

Via dinosaurs.about.com

T. rex: Doesn’t Need Friends

Dinosaurs as majestic and awesome as T. rex didn’t need anyone to have their back; other T. rexes might just scam off their delicious 500 pound-per-bite meals, so T. rex was a total loner who hunted by himself.

And guess what? If two T. rexes got into a scuffle, they just might fight to the death. The winner would eat the loser. It probably tasted just as delightful as Triceratops’ neck meat.

Via livescience.com

T. rex: Big Mouth

Do you really need proportional arms when your jaw alone is FOUR FEET LONG and can exert 3000 to 5000 lbs of force?

No. Not at all.

Via Wikipedia

T. rex: Small Arms? Still Huge

T. rex’s arms were over 3 feet long and may have been capable of bench pressing, oh …around 400lbs. In fact, studies have shown that T. rex’s arm muscles were over 3 times more powerful than an adult human’s.

Say something now, bro.

Via Wikipedia

14 Myths of the Velociraptor

Thursday, December 8, 2016

Jurassic Park III

1 – It’s no surprise that one of the most popular dinosaurs in the world is the Velociraptor. Their rise in popularity was heavily influenced by the way that they were portrayed in the ‘Jurassic Park’ films. While there may be some things about them that the films got right, there are some serious errors in their on screen depictions.

Velociraptor! Modern birds are closest to this species of dinosaur and prey species like eagles, hawks and owls are still commonly called ‘raptors’. Velociraptor, meaning “swift seizer” is a genus of dinosaur that lived approximately 75 to 71 million years ago during the later part of the Cretaceous Period. Two species are currently recognized. The fact that the ancestors of Velociraptor were feathered and possibly capable of flight had long suggested to paleontologists that Velociraptor bore feathers as well, since even flightless birds today retain most of their feathers. (Ottawa, Canada, June 2015) shankar s. – https://www.flickr.com/photos/shankaronline/20128517854/

2 – Velociraptors depicted in the Jurassic Park films more closely resembled the Deinonychus. These dinosaurs were more intimidating in nature, resulting in a better image for the onscreen Velociraptor.

3 – The movies depicts them as highly intelligent creatures who have the capacity to even open doorknobs. Unfortunately this is just not true as the smartest dinosaurs of the time were no smarter than a baby kitten.

4 – The movies show them attacking with their teeth and front claws, when in fact they would use their massive three-inch hind claw to attack their prey and let them bleed out while they wait from a safe distance.

5 – The name Velociraptor comes from the latin words “velox” (swift) and raptor (thief). The movies do depict the dinos as fast moving predators so at least they stayed true to the meaning of the name.

6 – Velociraptors were not around during the Jurassic period, but instead during the end of the Cretaceous period. The ‘Jurassic Park’ movies have confused people about this important fact since the original release.

Cretaceous Earth

7 – We are used to seeing them hunt in packs, especially so in the most recent film, yet there is no evidence that they do. This perception stemmed from evidence found that suggested the Deinonychus hunted in packs.

8 – Velociraptor tails contained fused bones that kept the tail straight and in the same position, aiding in balance during running, jumping, and attacking. In the films, you can see them moving their tails fluidly which is not at all how they would have looked.

9 – The movies lead viewers to believe that the Velociraptors originated in the Americas, however, fossil evidence suggest that they originated in central Asia.

Wikipedia

10 – Velociraptors were only about 1.6 feet tall at the hip, much shorter than depicted in the movies.

11 – Velociraptors are believed to have been able to run at speeds up to 40 mph which was actually pretty accurate compared to their speeds in the movies.

12 – Unlike the 100-pound version seen in the films, Velociraptors weighed in at about 30 pounds, making them very vulnerable to almost all carnivorous dinosaurs around at the time.

13 – Velociraptors did have feathers. While they did also have tough scaly skin, it wasn’t at all close to what was depicted in the films.

14 – Fun fact: The noises that the velociraptors made in the movies came from recordings of tortoises having sex. How fun.

How Do Scientists Determine The Age Of Dinosaur Bones?

Thursday, December 8, 2016

Fossilised bones of a dinosaur in Argentina

When paleontologist Mary Schweitzer found soft tissue in a Tyrannosaurus rex fossil, her discovery raised an obvious question — how the tissue could have survived so long? The bone was 68 million years old, and conventional wisdom about fossilization is that all soft tissue, from blood to brains, decomposes. Only hard parts, like bones and teeth, can become fossils. But for some people, the discovery raised a different question. How do scientists know the bones are really 68 million years old?

Today’s knowledge of fossil ages comes primarily from radiometric dating, also known as radioactive dating. Radiometric dating relies on the properties of isotopes. These are chemical elements, like carbon or uranium, that are identical except for one key feature — the number of neutrons in their nucleus.

The 67-million-year-old Tyrannosaurus rex skeleton known as Sue stands on display at Union Station on June 7, 2000, in Washington, D.C. MARK WILSON/NEWSMAKERS/GETTY IMAGES

Usually, atoms have an equal number of protons and neutrons. If there are too many or too few neutrons, the atom is unstable, and it sheds particles until its nucleus reaches a stable state. Think of the nucleus as a pyramid of building blocks. If you try to add extra blocks to the sides pyramid, they may stay put for a while, but they’ll eventually fall away. The same is true if you take a block away from one of the pyramid’s sides, making the rest unstable. Eventually, some of the blocks can fall away, leaving a smaller, more stable structure.

The result is like a radioactive clock that ticks away as unstable isotopes decay into stable ones. You can’t predict when a specific unstable atom, or parent, will decay into a stable atom, or daughter. But you can predict how long it will take a large group of atoms to decay. The element’s half-life is the amount of time it takes for half the parent atoms in a sample to become daughters.

To read the time on this radioactive clock, scientists use a device called a mass spectrometer to measure the number of parent and daughter atoms. The ratio of parents to daughters can tell the researcher how old the specimen is. The more parent isotopes there are — and the fewer daughter isotopes — the younger the sample. The half-life of the isotope being measured determines how useful it is at dating very old samples. Once all the parents have become daughters, there’s no more basis for comparison between the two isotopes. Scientists can’t tell whether the clock ran down a few days or millions of years ago. This means that isotopes with a short half-life won’t work to date dinosaur bones.

The short half-life is only part of the problem when dating dinosaur bones — researchers also have to find enough of the parent and daughter atoms to measure. Read on to see what it takes to date a fossil and what volcanic ash has to do with it.

An eagle flies over the Grand Canyon in Arizona, April 5, 2007. You can see the layers of sedimentary rock GABRIEL BOUYS/AFP/GETTY IMAGES

The most widely known form of radiometric dating is carbon-14 dating. This is what archaeologists use to determine the age of human-made artifacts. But carbon-14 dating won’t work on dinosaur bones. The half-life of carbon-14 is only 5,730 years, so carbon-14 dating is only effective on samples that are less than 50,000 years old. Dinosaur bones, on the other hand, are millions of years old — some fossils are billions of years old. To determine the ages of these specimens, scientists need an isotope with a very long half-life. Some of the isotopes used for this purpose are uranium-238, uranium-235 and potassium-40, each of which has a half-life of more than a million years.

Unfortunately, these elements don’t exist in dinosaur fossils themselves. Each of them typically exists in igneous rock, or rock made from cooled magma. Fossils, however, form in sedimentary rock — sediment quickly covers a dinosaur’s body, and the sediment and the bones gradually turn into rock. But this sediment doesn’t typically include the necessary isotopes in measurable amounts. Fossils can’t form in the igneous rock that usually does contain the isotopes. The extreme temperatures of the magma would just destroy the bones.

So to determine the age of sedimentary rock layers, researchers first have to find neighboring layers of Earth that include igneous rock, such as volcanic ash. These layers are like bookends — they give a beginning and an end to the period of time when the sedimentary rock formed. By using radiometric dating to determine the age of igneous brackets, researchers can accurately determine the age of the sedimentary layers between them.

Using the basic ideas of bracketing and radiometric dating, researchers have determined the age of rock layers all over the world. This information has also helped determine the age of the Earth itself. While the oldest known rocks on Earth are about 3.5 billion years old, researchers have found zircon crystals that are 4.3 billion years old [source: USGS]. Based on the analysis of these samples, scientists estimate that the Earth itself is about 4.5 billion years old. In addition, the oldest known moon rocks are 4.5 billion years old. Since the moon and the Earth probably formed at the same time, this supports the current idea of the Earth’s age.

Other Dating Methods

Radiometric dating isn’t the only method of determining the age of rocks. Other techniques include analyzing amino acids and measuring changes in an object’s magnetic field. Scientists have also made improvements to the standard radiometric measurements. For example, by using a laser, researchers can measure parent and daughter atoms in extremely small amounts of matter, making it possible to determine the age of very small samples.

Source: NewScientist.com

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