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Tyrannosaurus Rex: Not a tripod anymore

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An accurate skeleton of a Tyrannosaurus Rex Holotype specimen lumbers through the Carnegie Museum of Natural History in Pittsburgh (Image: Wikipedia commons, by Scott Robert Anselmo)

In 1915, paleontologist Henry Fairfield Osborn presented the world with a nearly complete skeleton of Tyrannosaurus Rex, towering over an exhibit space at the American Museum of Natural History, standing up straight like a kangaroo and balancing on its tail. The tripod pose was scientifically in error, but nearly 100 years later, students still can't get it right.

T. Rex skeleton installed at the Carnegie Museum in 1942 was similarly displayed, standing nearly 40 feet tall. Since the 1960s, scientists have realized that the upright pose could not be correct; in reality, the dinosaur's body was held more or less horizontal, with its tail balancing out its huge head, both cantilevered out from the huge rear legs. Its vertical height was 15-20 feet. But the museums took decades to correct their error. In any case, damage was done; the sight of that huge erect dinosaur had already been imprinted on several generations. Yale's Peabody museum is still happy to sell you coffee mugs and other memorabilia in which the dinosaur is depicted erect as in Rudolph Zallinger's famous mural, The Age of Reptiles.

Of course, it is not all the fault of the museums. The real T. Rex has spawned a multitude of comic book imitations and as well as Hollywood versions that have starred in untold numbers of bad science fiction films. Godzilla, a very T. Rex like monster, made its first appearance in 1954, and has gone on to be one of the most famous and profitable fictional characters ever, starring in at least 28 movies, and has appeared as well in comic books and TV series, both in its ancestral home of Japan and in the U.S.   

Cornell paleontologist Robert Ross and his colleagues recently performed a survey of students in which they were asked to draw a picture of T. Rex. Not surprisingly, the students got it wrong; 63% of pre-college and 72% of college students drew an upright T. Rex. Ross blames pop culture, although he credits Stephen Spielberg's Jurassic Park for portraying a more realistic version of the dinosaurs.

The real T. Rex had huge hind legs, surprisingly small albeit powerful fore- limbs and a huge head, with jaws that had a crushing power several times greater that of a great white shark. A mature T. Rex weighed over 5000 kilograms, but the animals did not start out life as monsters. The smallest T. Rex skeleton discovered came from an individual that weighed only about 30 kg and was perhaps two years old at death. A related tyrannosauroid from China was found to have proto-feathers, and it has been proposed that young T. Rex were similarly feathered. The feathers were replaced with scales as the animals aged and grew larger. But imagine a cute little T. Rex covered with downy feathers. Surely that is an image that Spielberg could do something with.