ZoomDinosaurs.com Dinosaur and Paleontology Dictionary

What Did Sauropods Eat?
Sauropods main food was probably conifers, which were the dominant plant when the large sauropods lived. Secondary food sources may have included Gingkos, seed ferns, cycads, bennettitalean, ferns, club mosses, and horsetails. Mid to late Cretaceous sauropods also probably ate flowering plants. DIfferent sauropods likely had different diets.

The exact diet of most dinosaurs (including sauropods) is not known. There are many ways determine what a dinosaur ate, including examining tooth structure, fossilized stomach contents, fossilized dung (called coprolites), but some of these methods rely on sparse or unavailable fossils evidence.

How Big Were Sauropods?
The sauropods ranged in size from the early Anchisaurids that were 7-10 feet (2-3 m) long to the later giants (like diplodocids, titanosaurids, and brachiosaurids) that were over 100 feet (30 m) long.

Why Were Sauropod Necks So Long?
No one knows why these plant eaters had such long necks. The Sauropod with the longest neck was Mamenchisaurus, whose neck was about 46 feet (14 m) long, over half of the animal's length.

Different sauropods had different neck stances. The Brachiosaurids (like Brachiosaurus, Sauroposeidon, and Ultrasauros) held their necks vertically, in a giraffe-like manner. They probably used their long necks in the same way that modern-day giraffes do, to get leaves that are high in the trees.

Other sauropods (like diplodocids) held their necks more-or-less horizontally (parallel to the ground). These long necks may have been used to poke into forests to get foliage that was otherwise unavailable to the huge, lumbering varieties of sauropods who could not venture into forests because of their size. Alternatively, the long neck may have enabled the sauropods to get soft pteridophytes (horsetails, club mosses, and ferns). These soft-leaved plants live in wet areas, where sauropods couldn't venture, but perhaps the sauropod could stand on firm ground and browse in wetlands.

Sauropods' Brain:
It used to be thought that the sauropods had a second brain at the base of the tail. Paleontologists now realize that what they thought was a second brain was perhaps an enlargement in the spinal cord in the hip area (although this is not universally accepted), containing nerves and fatty tissue. This enlargement was larger than the animal's tiny brain and may have controlled the animal's hind legs and tail.

When Did Sauropods Live?
Sauropods appeared in the late Triassic period and were common, widespread, and diverse by the Jurassic period. They went extinct at the end of the Cretaceous period (65 million years ago), along with the other remaining dinosaurs. Sauropods have been found on all continents except Antarctica. They are the largest land animals ever discovered.

Classification:
Sauropods were Saurischians (the order of lizard-hipped dinosaurs that were probably the ancestors of birds). They were also an infraorder of the Suborder Sauropodomorpha.

SAUROPODS
	Plant eaters (herbivores) Small heads with spatulate or pencil-shaped teeth Long neck Usually walked on four legs Largest land animals ever!

Some major sauropod families:

• Diplodocids (meaning "Double beams") - Whip-like tail, very long neck, small head, nostril above eyes, pencil-like teeth only in the front of the mouth, hollows in vertebrae. Lived from the late Jurassic to the end of the Cretaceous. Examples include: Diplodocus, Apatosaurus, Amargasaurus, Atlantosaurus, Barosaurus, Mamenchisaurus, Quaesitosaurus, Nemegtosaurus, Seismosaurus, Supersaurus, and others. Length: 55-90 ft (17-27 m).
• Brachiosaurids (meaning "Arm lizards") - A giraffe-like stance, front legs longer than the rear legs, short, thick tail, chisel-like teeth, nostrils above the eyes. Lived only from the mid-late Jurassic to the early Cretaceous. Examples include: Brachiosaurus, Sauroposeidon, Ultrasauros, (a dubious genus). Length: 33-100 ft (10-30 m)
• Camarasaurids (meaning "Chambered lizards") - Relatively short neck and tail (as compared to other sauropods), hollowed-out chambers in their vertebrae and a relatively big (for a sauropod), box-like head, chisel-like teeth all along jaws, and nostrils above and ahead of the eyes. Lived from the late Jurassic to the end of the Cretaceous. Examples include: Camarasaurus, Algoasaurus, Aragosaurus, Asiatosaurus, Cathetosaurus, Chiayuesaurus, Opisthocoelicaudia, Parrosaurus, and others. Length: 40-60 ft (12-18 m).
• Titanosaurids (meaning "Titanic lizards") - Armored skin (bony plates, sometimes with horny spikes), a wide head, peg-like teeth, and vertebrae not hollowed out. Lived from the late Jurassic to the end of the Cretaceous. Examples include: Titanosaurus, Aegyptosaurus, Aepisaurus, Alamosaurus, Antarctosaurus, Argyrosaurus, Hypselosaurus, Janenschia, Laplatasaurus, Loricosaurus, Macrurosaurus, Microcoelus, Paralititan, Saltasaurus, and others. Length: 30-130 ft (9-35 m).
• Cetiosaurids (meaning "Whale lizards") - Had almost solid vertebrae and a shorter tail. Lived from the early Jurassic to the middle Cretaceous. Examples include: Cetiosaurus, Amygdalodon, Austrosaurus, Barapasaurus, Bellusaurus, Dachongosaurus, Datousaurus, Dystrophaeus, Haplocanthosaurus, Kumingosaurus, Lapparentosaurus, Ohmdenosaurus, Oshanosaurus, Patagosaurus, Protognathus, Rhoetosaurus, Shunosaurus, Volkheimeria, and Zizhongosaurus. Length: 30-60 ft (9-18 m).

Sauropoda (large, 4-legged herbivores)
AMARGASAURUS	APATOSAURUS

BAROSAURUS

BRACHIOSAURUS

CAMARASAURUS

DIPLODOCUS

JANENSCHIA

MAMENCHISAURUS

PARALITITAN

QUAESITOSAURUS

SALTASAURUS

SEISMOSAURUS

SUPERSAURUS

ULTRASAUROS

VULCANODON

ZIGONGOSAURUS