Sauropod Dinosaur Egg

Sauropod Egg. Fossil replica. Upper Cretaceous (Campanion) Outer Mongolia.

* Size: 5.3 inch x 4.7 inch (13cm x 12cm)
* Embedded in 7 inch x 6 inch (18cm x 15cm) base
* 2.5 lbs
* Museum quality
* Cast in durable Polyurethane resins.
* Made in USA

Sauropods' most defining characteristic was their size. Even the dwarf sauropods (perhaps 5 to 6 metres, or 20 feet long) were counted among the largest animals in their ecosystem. Their only real competitors in terms of size are the rorqual whales, such as the Blue Whale. But unlike whales, sauropods all lived on land. Some, like the diplodocids, probably held their heads low, while others, like Camarasaurus, held them high.

Their body design did not vary as much as other dinosaurs, perhaps due to size constraints, but they still displayed ample variety. Some, like the diplodocids, were extremely long and with tremendously long tails which they may have been able to crack like a whip to make sonic booms. Supersaurus, at 40 metres (130 ft), is probably the longest, but Seismosaurus and even the old record holder, Diplodocus, are still extremely long. Amphicoelias fragillimus, of which only a drawing of a single vertebra survives, at 55 to 60 metres (180 to 200 ft) would have a spine even longer than the blue whale. The longest terrestrial animal alive today, the reticulated python, only reaches lengths of 10 metres (33 ft).

Others, like the brachiosaurids, were extremely tall, with high shoulders and extremely long necks. Sauroposeidon is probably the tallest, reaching about 18 metres (60 ft) high, with the previous record for longest neck being held by Mamenchisaurus. By comparison the giraffe, the tallest of all living animals, is only 4.8 to 5.5 metres (16 to 18 ft) tall.

Some were almost incredibly massive: Argentinosaurus is probably the heaviest at 80 to 100 metric tonnes (90 to 110 tons), though Paralititan, Andesaurus, Antarctosaurus, and Argyrosaurus are of comparable sizes. There is some very poor evidence of an even more massive titanosaurian, Bruhathkayosaurus, which might have weighed between 175 to 220 tonnes (190 to 240 tons). The largest land animal alive today, the Savannah elephant, weighs no more than 10 tonnes (11 tons).

Among the smallest sauropods were the primitive Anchisaurus (2.4 m, or 7 ft long) and Ohmdenosaurus (4 m, or 13 ft long), the dwarf titanosaur Magyarosaurus (5.3 m or 17 ft long), and the dwarf brachiosaurid Europasaurus, which was 6.2 meters long as a fully-grown adult. Its small stature was probably the result of insular dwarfism of a herd of sauropods stranded on an island in what is now Germany. Also notable is the diplodocoid sauropod Brachytrachelopan, which was the shortest member of its group thanks to its unusually short neck. Unlike other sauropods, whose necks could grow to up to four times the length of their backs, the neck of Brachytrachelopan was shorter than its backbone.