Diplodocus Foot

What does quadrupedal mean?

| A A quadrupedal animal, such as Saltasaurus, is one that walks on all four legs. All sauropods, and most other plant-eating dinosaurs, were quadrupedal. This was probably because the plant-eaters had large stomachs that tended to pitch their bodies forward onto the front legs, making walking on only the back legs impossible.

i-tl

Front legs slightly shorter then back legs

Saltasaurus

Elbow joint

Magyarosaurus

Magyarosaurus

Were there any small sauropods?

| A One of the smallest known sauropods measured 20 ft (6 m) from head to tail. Magyarosaurus and other smaller sauropods have been discovered in parts of Europe that were a group of islands in Cretaceous times. It is likely that the sauropods living there became smaller over thousands of years because of a limited food supply.

How long was the longest neck?

I A The neck of an adult Mamenchisaurus was an incredible 46 ft (14 m) long. The neck was made up of 19 spinal bones (vertebrae), more than in any other dinosaur. The vertebrae were linked to one another by bony struts, which made the neck quite stiff. The vertebrae were hollow and thin to make the neck as lightweight as possible.

Dinosaurier Broncosaurus

Small intestine

Tail was thick at its base

Small intestine

Tail was thick at its base

Backbone

Saurischian (lizard) hips r à

Who had the longest tail?

| A Diplodocus is the most likely holder of this title. This dinosaur had a tail measuring around 46 ft (14 m), as long as Mamenchisaurus's neck. The tail was composed of about 80 vertebrae, which became narrower at the tail's tip. Diplodocus probably used its tail as a counterbalance for its long neck and it may have whipped attackers with its tail, too.

i Muscular tail

Running Long Neck Dinosaurs

Large intestine

Saltasaurus Armor

Did sauropods have thick skin?

I A Sauropods had thick skin for protection against attackers. However, these skin textures would have varied between groups. A section of fossilized skin from a Saltasaurus, above, has been discovered, showing bumpy skin inset with little bony plates. Other sauropods may have had smoother, more lizardlike skin. Some even had ridged spikes running along their backs.

Brachiosaurus

Strong muscles

Ankle joint f

Was bigger always better?

As tens of millions of years passed, the sauropods and theropods grew ever larger. It seems that they were locked into an evolutionary size race—as the theropods became larger and more fierce, the sauropods grew bigger to counter any attack. In the end, sauropods such as Camarasaurus dwarfed Allosaurus and the other theropods. Being massive, however, had its disadvantages, such as lack of speed. Meanwhile, other plant-eating dinosaurs developed alternative methods of defense, often growing too tough or too nimble for theropods to tackle.

Sauropod is 75 ft (3 m) long

Giant Plant Eating Dinosaurs

Were all the plant-eaters huge?

Not all plant-eating dinosaurs became enormous in response to the threat of theropods. Gargoyleosaurus was 10—1 3 ft (3—4 m) long, one of the smallest of the ankylosaur group. Although relatively small. Gargoyleosaurus was capable of surviving an attack by a theropod. Its vicious shoulder spikes and bony back plates would have made it a tough meal.

Gargoyleosaurus

Gargoyleosaurus

Gargoyleosaurus

Did sauropods have extra-powerful hearts?

| A Some experts think that the bigger sauropods, such as Brachiosaurus may have needed large, powerful hearts and super-high blood pressure to pump blood around their massive bodies and up their necks to their brains. It is possible that they had hearts with four chambers, like humans and other mammals, rather than three chambers, like most reptiles.

Brachiosaurus

Brachiosaurus Digestive System

Brachiosaurus

Stiff neck ending in small head

Stiff neck ending in small head

How did sauropods carry their weight?

| A Experts once thought that sauropods lived in water because they would have been too heavy to support their own weight. Today, they agree that sauropods were designed to carry their weight, just as elephants are. Their legs were as sturdy as pillars and their toes, which splayed out to spread the weight, were cushioned by big pads of flesh. A large fleshy heel helped support the weight.

Dryosaurus

Elephant And Diplodocus Foot Compared

Diplodocus forefoot

Elephant forefoot

Diplodocus forefoot

Elephant forefoot m

What do fossil footprints tell us?

| A To estimate how fast a dinosaur moved, paleontologists examine the anatomy of the animal and, where available, its footprints. They can figure out its moving speed by measuring distance between the tracks— although footprints from a running dinosaur are very rare. These Brontopodus tracks indicate that the large sauropods had a top speed of about 6 mph (10 km/h).

Could a plant-eater be quick on its feet?

Not all plant-eaters were big or covered with body armor—some used their agility to escape danger. The ornithopod group of dinosaurs included lightly built animals such as Dryosaurus, which could run at high speeds. Like the theropods, Dryosaurus had a stiff tail for balancing as it sprinted on its hind legs.

Dryosaurus

Long, lightly built legs

Could Saltasaurus rear up on its hind legs?

The skeletons of Saltasaurus and some other sauropods suggest that they may have been able to rock back onto their hind legs and lift their front legs off the ground to reach foliage high up in the trees.

1 Slightly longer hind legs meant that the dinosaur's weight could be shifted to the back of the animal.

2 Once on its hind legs, the dinosaur's center of gravity was shifted to the back half of its huge body.

3 The tail acted as a third leg, providing extra stability as the dinosaur balanced on its two hind legs.

Could Saltasaurus rear up on its hind legs?

The skeletons of Saltasaurus and some other sauropods suggest that they may have been able to rock back onto their hind legs and lift their front legs off the ground to reach foliage high up in the trees.

How did plant-eaters find food?

Plants common in the age of the dinosaurs included ginkgo trees, palmlike trees, coniferous trees, and ferns and mosses. It is likely that herbivorous dinosaurs ate all these plants. Different plant-eating dinosaurs developed different ways of breaking down their food. Sauropods, such as Barosaurus, raked foliage into their mouths with peglike teeth and swallowed it whole. It was then broken down in their digestive systems. Other plant-eating dinosaurs ground down plant matter with their teeth before swallowing.

Barosaurus

ii sEml*

Modern-day ginkgo

Modern-day ginkgo

Fossilized ginkgo

Was this article helpful?

0 0

Responses

  • Claudia
    How fast does a dryosaurus run?
    9 years ago
  • futsum
    Did a brachiosaurus have spikes?
    9 years ago
  • yerusalem yonas
    What dinosour had the longest legs?
    9 years ago

Post a comment