From Head To Tail

Dinosaurs, like humans, belong to a group of animals called vertebrates. The key feature of all vertebrates is the spine - a stiff rod made up of small bones running from the head to the tail. The spines of dinosaurs reveal a great deal about the way they moved. In some dinosaurs, the bones of the spine were joined by flexible joints, allowing these dinosaurs to swing their necks and tails at will. In others, rodlike stiffeners made parts of the spine rigid. The rear part of the spine formed the tail, which provided sharply like a bison's. Bison bend theft / ^^^^MBIIk jfl^^^f*1 I^B

necks to eat ground plants like grass, Parasaurolophus/ :

Parasaurolophus

Tails for agility

Unusual tails helped Dromaeosaurus and its close relative Velociraptor produce the sudden turns that made their swift attacks so deadly. Most of the tail bones were locked together by special bony rods to form a stiff bar; only where the tail met the hips was it free to move around. This combination of stiffness and flexibility allowed these predators to raise and swing their tails in any direction. Balancing like acrobats, they could turn at high speed and twist in midair while leaping to strike a victim.

The sickle-shaped claws were used to slash through skin.

Flesh-eating dinosaurs tended to have an S-shaped neck.

Dromaeosaurus Size

Dromaeosaurus

Flesh-eating dinosaurs tended to have an S-shaped neck.

Dromaeosaurus

The large back claw flicked forwards as Dromaeosaurus kicked at its prey.

Dromaeosaurus

Dromaeosaurus was about 6 ft (1.8 m) long - about the same size as Velociraptor. Like Velociraptor, this animal was a rapacious predator.

The large back claw flicked forwards as Dromaeosaurus kicked at its prey.

Dromaeosaurus was about 6 ft (1.8 m) long - about the same size as Velociraptor. Like Velociraptor, this animal was a rapacious predator.

from head to tail

Ornithomimus

Ornithomimus

Ornithomimus's stiff tail helped it balance while running at high speed.

Tails for balance

Long, tapered tails held level with the ground helped ostrich dinosaurs, such as Ornithomimus, to balance the front of the body while they ran. Their tails contained up to 40 bones, those in the rear held together by bony prongs that served as stiffeners. By swinging its tail from side to side, a sprinting Ornithomimus could make sudden turns to fool its enemies.

its enemies.

Dromaeosaurus's tail could bend only at the base.

Dromaeosaurus Bone

Dromaeosaurus's tail could bend only at the base.

Smashing tails

Euoplocephalus's secret weapon was a heavy-duty club on the end of its tail. If a predator tried to attack, Euoplocephalus would turn and smash the club into its assailant's legs, perhaps breaking bones or knocking the animal over. If the club failed to deter an attack, Euoplocephalus's armored skin provided a second line of defense.

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Stegosaurs

The bony spikes and plates of stegosaurs were not joined to the spine, but simply set into the skin. Each type of stegosaur had spikes or plates of a distinctive shape. Perhaps these structures helped them recognize each other. Flat plates may also have regulated heat,

Stegosaurus

Kentrosaurus

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Euoplocephalus

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Diplodocus's neck was, about 26 ft (8 w) long.

how many bones?

The sauropods had the longest spines of any land animals. Diplodocus's spine - measured from the back of its head to the tip of its tail - was more than 85 ft (26 m) long. Its neck was made up of 15 bones; by comparison, the neck of a human or a giraffe contains only 7 bones. But the world record was held by another sauropod, Mamenchisaurus. Its neck alone was 49 ft (15 m) long - longer than a giraffe's entire body - and was made up of 19 neck bones.

Diplodocus

! The long tail was made up of about 70 bones. When Diplodocus moved its head to the left, it moved the tail to the right to stay balanced.

SUITS OF ARMOR

Canned food only makes a meal if you have a can opener. To a flesh-eating dinosaur, armored prey were like walking meals that were impossible to get at because of the studs, plates, and spikes that protected them. These suits of armor enabled their plant-eating owners to outwit predators for tens of millions of years. During that time, the armored dinosaurs evolved from small, lightweight species with just a few rows of studs on their backs into huge lumbering beasts as heavy as elephants and shielded like battle tanks.

Suit of spikes

Gastonia (right) was a walking fortress as long as a racquetball court is wide. Short legs and a low build kept its body close to the ground, protecting its belly from attack. Large bony spikes stuck out from its shoulders and ran down its back and tail, protecting the upper body. So much for its passive defenses; Gastonia could also counterattack by swinging its armored tail violently to the side. Such defenses were vital to this herbivore, because it lived at the same time as Utahraptor, a savage predator built like Velociraptor but twice its size.

Ferns were abundant in Gastonia's time, but their tough fibrous stems might have made them difficult to digest.

Ferns were abundant in Gastonia's time, but their tough fibrous stems might have made them difficult to digest.

^ Favorite food

Gastonia held its head low and so could eat only plants at ground level or just above. Most likely, it cropped the soft, fleshy

/"flowers" of some seed-ferns - prehistoric plants with fernlike fronds that sprouted from stubby tree trunks. Horsetails and ferns were probably plentiful, but their stems might have been too tough for Gastonia's teeth.

Edmontonia

Edmontonia resembled a gigantic, prickly armadillo. Bands of thorny plates ran across its back and tail, and large bony spikes shielded its neck and shoulders. Its skull was protected by smaller plates of bone that fitted together like a jigsaw puzzle. A big carnivore might have tried overturning Edmontonia to attack its soft underbelly. But Edmontonia could fight back by charging at the attacker and stabbing its shoulder spikes into their flesh.

Shoulder spike ir J

Shoulder spike

, Flank spike

Edmontonia

Armored tail

Stocky legs suits of armor

hain mail lese two photographs show a '.uropelta from above and belo Lck (top) was covered with b( laller bony studs. These form mor that let it move around knight in chain mail. But its ! ottom) was less well defende ight have had to crouch duri

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Responses

  • albertino
    What made up pre historic earth?
    8 years ago
  • RUSSOM
    What kind of food did the dromaeosaurus eat?
    8 years ago

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