Prehistoric Animals : Stegosaurus

Stegosaurus

Although nowhere near the largest of the Jurassic dinosaurs, Stegosaurus were still about the size of a bus. Distinctive and heavily built, they were herbivores with short forelimbs and would have walked with their small head close to the ground and the four-spiked tail held high. The double row of plates running along the back helped control body temperature and were probably used in display or possibly in defence against carnivorous Allosaurs. Most fossils for the three known species, including some complete skeletons, have come from the USA, although a recent discovery in Portugal suggests a wider distribution.

Scientific name: Stegosaurus
Rank: Genus

roof-lizard

Stegosaurus (pron.: /ˌstɛɡɵˈsɔrəs/, meaning "roof lizard" or "covered lizard" in reference to its bony plates) is a genus of armored stegosaurid dinosaur. They lived during the Late Jurassic period (Kimmeridgian to early Tithonian), some 155 to 150 million years ago in what is now western North America. In 2006, a specimen of Stegosaurus was announced from Portugal, showing that they were present in Europe as well. Due to its distinctive tail spikes and plates, Stegosaurus is one of the most recognizable dinosaurs. At least three species have been identified in the upper Morrison Formation and are known from the remains of about 80 individuals.
A large, heavily built, herbivorous quadruped, Stegosaurus had a distinctive and unusual posture, with a heavily rounded back, short forelimbs, head held low to the ground and a stiffened tail held high in the air. Its array of plates and spikes has been the subject of much speculation. The spikes were most likely used for defense, while the plates have also been proposed as a defensive mechanism, as well as having display and thermoregulatory functions. Stegosaurus had a relatively low brain-to-body mass ratio. It had a short neck and small head, meaning it most likely ate low-lying bushes and shrubs. It was the largest of all the stegosaurians (bigger than genera such as Kentrosaurus and Huayangosaurus) and, although roughly bus-sized, it nonetheless shared many anatomical features (including the tail spines and plates) with the other stegosaurian genera.

 

Prehistoric Animals : Velociraptors

Velociraptors

Velociraptors were made famous in the film 'Jurassic Park', though they were a little less impressive in reality, standing not much taller than domestic turkeys. A famous fossil has one locked in battle with a Protoceratops. The predatory Velociraptor had pinned down its plant-eating victim, but both appear to have been overcome, perhaps by a sudden sandstorm. Fossils also show that Velociraptor had large feathers on its forelimbs, perhaps used for display.

Scientific name: Velociraptor
Rank: Genus

Common names:swift seizer

Velociraptor (pron.: /vɨˈlɒsɨræptər/; meaning 'swift seizer') 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.
Smaller than other dromaeosaurids like Deinonychus and Achillobator, Velociraptor 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 kill its 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 the films it was shown with anatomical inaccuracies, including being much larger than it was in reality and without feathers. It is also 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.

Prehistoric Animals : Carcharodontosaurids

Carcharodontosaurids

The carcharodontosaurids were a group of giant carnivorous dinosaurs that rivalled and even exceeded Tyrannosaurus in size. Scientists have calculated that one of them, Giganotosaurus, could run at 50 km/h, which is just slower than an ostrich, but 13 km/h faster than a gold medal-winning Olympic sprinter. Carcharodontosaurids were top predators in the ancient continent of Gondwanaland: the area of the world that's now the southern hemisphere continents - South America, Africa, Antarctica, Australia - and India. They evolved from an Allosaurus-like ancestor and became extinct about 89 million years ago.

Scientific name: Carcharodontosauridae
Rank: Family

Shark-toothed lizards

Carcharodontosaurids (from the Greek Carcharodontosauros: "shark-toothed lizards") were a group of carnivorous theropod dinosaurs. In 1931 Ernst Stromer named Carcharodontosauridae as a family, in modern paleontology this name indicates a clade within Carnosauria. Carcharodontosaurids included some of the largest land predators ever known: Giganotosaurus, Mapusaurus, Carcharodontosaurus, and Tyrannotitan all rivaled or exceeded Tyrannosaurus in size.

Prehistoric Animals : Ceropod Dinosaurs

Ceropod dinosaurs

Ceropod dinosaurs were all plant-eaters and include the horned and duck-billed dinosaurs. The secret of their success was in their teeth. These were much more efficient at grinding up plant food than your typical dinosaur's dentition, so cerapods were able to extract more nutritional value from their food and tackle plants that others found too tough to digest. It wasn't until big herbivorous mammals evolved that such efficient chewing teeth were seen again on Earth.

Scientific name: Cerapoda
Rank: Suborder

Common names: horn foot

Cerapoda ("ceratopsians and ornithopods") is a clade of the dinosaur order Ornithischia.

Prehistoric Animals : Sauropodomorph dinosaurs

Sauropodomorph dinosaurs

Sauropods are among the most famous and recognisable dinosaurs: long-necked, long-tailed giants that include Diplodocus and Brachiosaurus. Early sauropods were bipedal and quite small compared to their later descendants which became the heaviest and longest dinosaurs. It requires a four-legged stance to get to truly giant size, as you need to spread your weight. Like elephants today, the largest sauropods could only move at a walk as their leg bones couldn't withstand the impact of trotting or galloping gaits. However, just because they were restricted to walking didn't mean they couldn't put on a turn of speed: their top walking speed has been estimated at between 20 and 35 km/h.

Scientific name: Sauropodomorpha
Rank: Suborder

Sauropodomorpha (pron.: /sɔːˌrɒpɵdəˈmɔrfə/ saw-ROP-ə-də-MOR-fə; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The "prosauropods", which preceded the sauropods, were smaller and were often able to walk on two legs. The sauropodomorphs were the dominant terrestrial herbivores throughout much of the Mesozoic Era, from their origins in the mid-Triassic until their decline and extinction at the end of the Cretaceous.

Prehistoric Animals : Ornithopod Dinosaurs

Ornithopod dinosaurs

With some of the most advanced chewing apparatus ever developed by a reptile, ornithopod dinosaurs became a most successful group of herbivorous dinosaurs. They rapidly became a prominent feature on North America's Cretaceous landscape, until they were wiped out by the famous Cretaceous-Tertiary, or K-T, extinction event. Early ornithopods were only about a metre long and could probably run very fast on their hind legs. They evolved to become as large as some of the mighty sauropods, walking and grazing on all four legs, but still using the hind legs for running and reaching up into trees. Notable ornithopods include the duck-billed hadrosaurs and, of course, iguanodon.

Scientific name: Ornithopoda
Rank: Infraorder

Common names:bird feet

Prehistoric Animals : Common names:

Duck-billed dinosaurs

Duck-billed dinosaurs were successful and common herbivores from the upper Cretaceous period. The secret of their success perhaps lay with the duck-shaped bill that clipped vegetation and the many small teeth that ground it down. There were two types: some with a bony crest on their head for resonating sound and some without. Fossilised nest sites have shown that some species may have travelled to communal nesting grounds to lay eggs, as many bird species do today. Fossils from the many species are found all over modern-day Europe, Asia and North America, and show that some grew to around 12 metres.

Scientific name: Hadrosauridae
Rank: Family

Common names:bulky lizard, Hadrosaurs

Hadrosaurids or duck-billed dinosaurs are members of the family Hadrosauridae, and include ornithopods such as Edmontosaurus and Parasaurolophus. They were common herbivores in the Upper Cretaceous Period of what are now Asia, Europe and North America. They are descendants of the Upper Jurassic/Lower Cretaceous iguanodontian dinosaurs and had similar body layout. They were ornithischians.
Hadrosaurids are divided into two principal subfamilies. The lambeosaurines (Lambeosaurinae) had hollow cranial crests or tubes, and were generally less bulky. The saurolophines, identified as hadrosaurines in most pre-2010 works (Saurolophinae or Hadrosaurinae), lacked hollow cranial crests (solid crests were present in some forms) and were generally larger.

Prehistoric Animals : Lizard-hipped dinosaurs

Lizard-hipped dinosaurs

The earliest known dinosaurs, lizard-hipped dinosaurs first appeared in the mid Triassic. As well as these first dinosaurs, the order includes all the carnivorous dinosaurs and one group of herbivores - the sauropods and their close relatives. The name 'lizard-hipped' comes from the shape of their pelvis, in which the pubis points towards the front of the animal. Birds are descended from this group of dinosaurs.

Scientific name: Saurischia
Rank: Order

Lizard-hipped

Prehistoric Animals : Gigantoraptor

Gigantoraptor

In 2005, a Chinese palaeontologist filming sauropod bones in Mongolia came across an unidentified thigh bone. It was a fortunate discovery. The bone belonged to a creature that may have been eight metres in length and more than two tons in weight. Gigantoraptor, as it was subsequently named, is the largest feathered dinosaur discovered to date.

It is 35 times bigger than the next largest species of Oviraptorid. The toothless skull of this bird-like dinosaur was more than half a metre long with a horny beak. It had long hind legs and large claws and would have been fast enough to outrun most predators around 70 million years ago. It seems certain that Gigantoraptor's feathers were for display rather than for flight or insulation.

Scientific name: Gigantoraptor
Rank: Genus

Prehistoric Animals : Bird-hipped dinosaurs

Bird-hipped dinosaurs

Bird-hipped dinosaurs derive their name from the shape of their pelvis, which resembles that of modern birds, whose pubis points to the rear of the animal. Unexpectedly, birds did not evolve from these dinosaurs, but from the lizard-hipped dinosaurs, since this shape of pelvis has evolved more than once. Another distinguishing characteristic of the bird-hipped dinosaurs was a horny beak, which they used to crop plants, much like a horse or deer uses its front teeth today. Duck-billed dinosaurs, horned dinosaurs and armoured dinosaurs were all of the bird-hipped variety.

Scientific name: Ornithischia
Rank: Order

Common names:Bird-hipped

Ornithischia (pron.: /ɔrnɨˈθɪskiə/ or-ni-THISS-kee-ə) or Predentata is an extinct order of beaked, herbivorous dinosaurs. The name ornithischia is derived from the Greek ornitheos (ορνιθειος) meaning 'of a bird' and ischion (ισχιον) meaning 'hip joint'. They are known as the 'bird-hipped' dinosaurs because of their bird-like hip structure, even though birds actually belong to the 'lizard-hipped' dinosaurs (the saurischians). Being herbivores that sometimes lived in herds, they were more numerous than the saurischians. Many were prey animals for the theropods and were usually smaller than the sauropods.

Prehistoric Animals : Utahraptor

 

Utahraptor

Utahraptor is the largest of the dromaeosaurs, which are also known as raptors. It measured about 6 or 7 metres long and would have weighed more than a polar bear. It had a huge claw on each hind foot which it held clear of the ground as it ran to keep it sharp and ready for action. Its hind limbs were relatively stocky, since it needed power rather than speed to use the deadly claws to kick or cling on to struggling prey. The claws on its hands were also larger and more blade-like than those of other raptors.

Scientific name: Utahraptor
Rank: Genus

Cretaceous period

The Cretaceous ended with the most famous mass extinction in history - the one that killed the dinosaurs. Prior to that, it was a warm period with no ice caps at the poles. Much of what we now know as dry land - such as southern England and the midwest of the USA - was underwater, since sea levels reached their highest ever during this time. The Atlantic Ocean grew much wider as North and South America drew apart from Europe and Africa. The Indian Ocean was formed at this time, and the island that was India began its journey north towards Asia.

Began: 142 million years ago

Ended: Cretaceous-Tertiary mass extinction
65 million years ago

Triassic period

The Triassic began after the worst mass extinction ever, at the end of the Permian. Life on Earth took a while to recover and diversify. The Triassic was characterised by heat, vast deserts and warm seas. Even the polar regions were warm, so lush forests grew there. However, the lack of other life, coupled with the period's particular environmental conditions, opened up some evolutionary opportunities. As a result, the very first mammals and dinosaurs evolved. During this time, the giant supercontinent of Pangaea began to break apart. The period ended as it had begun, with an extinction event that wiped out many species.

Began: Permian mass extinction
248 million years ago

Ended: Triassic-Jurassic mass extinction
205 million years ago

Jurassic period

The Jurassic began after the mass extinction event that ended the Triassic. Life, however, was quick to recover from this blow and the Jurassic eventually became host to the most diverse range of organisms that Earth had yet seen. Amongst them were the first birds and some of the dinosaurs. Continental break-up during this time gave rise to the sea that would eventually widen to become the Atlantic Ocean. The ocean floor that formed at this time is the oldest surviving on the planet - all older ones having now been 'recycled' through plate tectonics.

Began: Triassic-Jurassic mass extinction
205 million years ago

Ended: 142 million years ago

Prehistoric Animals : Allosaurus

Allosaurus

Allosaurus were big, mean killing machines that reigned supreme during the late Jurassic period. They were the most common huge predators in North America 140 million years ago, reaching an impressive 12 metres in length and weighing up to four tonnes. These carnivorous dinosaurs could rip and tear chunks out of the large plant-eating sauropods and stegosaurs of the time. The enormous jaw was filled with long, serrated, back-curving teeth. Near perfect examples of this classic shaped theropod dinosaur were discovered in Wyoming and called Big Al and Big Al Two. Allosaurus fossil remains are extremely rare outside America.

At 9 metres and 1.5 tonnes, Allosaurus was a formidable Jurassic hunter. But its bite was surprisingly weak - However it had the element of surprise in its attacks

Scientific name: Allosaurus
Rank: Genus

Prehistoric Animals : Theropod Dinosaurs

Theropod dinosaurs were the top predators in the Jurassic and Cretaceous periods. For over 100 million years theropods were the only large carnivores on land and included all the infamous carnivorous dinosaurs - Tyrannosaurus, Velociraptor and Spinosaurus. However, not all theropods were predators. Some evolved away from their carnivorous origins to consume an omnivorous or herbivorous diet. Birds are the only living descendants of the theropods.

Scientific name: Theropoda
Rank: Suborder

beast-footed

Prehistoric Animals ; Brachiosaurus

Brachiosaurus