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Profile
True to life?

Profile

Species: cazaui
Range: Early Cretaceous (Barremian-Aptian, 130-122 MYA) of Neuquen province, Argentina
Size estimate: 30 ft length, 4-5 tons
Discovery: Leonardo Salgado and José F. Bonaparte, 1991
Classification: dinosauria, saurischia, sauropoda, diplodocoidea, dicraeosauridae

True to Life?

Since no one has ever seen a living dinosaur, and the missing pieces of the fossil record withhold important clues to their appearance, no artistic representation of a dinosaur ever gets it 100% right. On top of that, new discoveries can change our ideas of extinct creatures drastically. So, how close does this sculpture come to what we know of the original animal?

• Science knows Amargasaurus from only one specimen, so it’s a good thing it’s a nearly complete skeleton. We know its skeletal anatomy from the base of its skull to the base of its tail, with a few tail bits here and there. It belongs to the dicraeosaur family, which is an evolutionary spin-off of the diplodocid family; its head therefore likely shared their horse-like profile, but the details of the head on this sculpture remain a complete guess otherwise.
• Having the back of the head at least tells us the correct proportions the head should fit, and this head is somewhat too big.
• Amargasaurus’ claim to fame grows from the back of its neck. This sculpture presents an early theory that the spines supported a dual “sail” of skin running down the neck and back. Rough textures on these spines have led later researchers to favor reconstructions that cover them in keratin, the same substance that sheathes horns. Those spines didn’t have the girth to act as weapons, but they may have presented an intimidating defensive display nonetheless. The single spines on its first two neck vertebrae—the atlas and axis bones—likewise better support spines instead of sails. Sail reconstructions like this one tend to ignore that little-known detail.
• Another detail many reconstructions, including this one, seem to miss deals with the placement of these spines. They grew only 2-3 inches apart—some scientists have tentatively suggested that perhaps they formed a single skin-sail with a hollow space inside. The spines extended roughly parallel to one another or bowed slightly inward on some of the bones of its back.
• Though sauropods typically grew long necks and gigantic sizes, Amargasaurus bucked that trend—its relatively small size and shortish neck as depicted here match what we know of the species.
• As with most of the other dinosaurs of the park, colors here follow only general animal trends. The brighter colors on the neck correspond with their presumed display role. The overall greenish color could work as camouflage. The scientists who first described this species regarded it as slow and incapable of rearing on its hind legs due to its short legs and a number of oddities of its backbones beyond having those strange spines. Without speed or size, camouflage with the ability to create a surprising display strike us as plausible compensation, and we have colored it accordingly.
• Behind the scenes: Perhaps due to the spines’ resemblance to a horse’s mane, model and toy makers have often colored their Amargasaurus offerings with traditionally feminine color schemes, as if they were dinosaurian My Little Ponies. Don’t think we weren’t tempted to illustrate that trend with this sculpture! But what would its Cutie Mark look like?
• Behind the scenes: Maintenance on this sculpture further undermines the sail model. Dual sails form a dead-end trough that collects leaves and pine cones like the dickens! The sculpture therefore also features inconspicuous holes for draining the water from the space between the sails. A living animal might be able to deal with this problem differently, but it would still prove mightily inconvenient in many ways.