Family: Brachiosauridae (intermediate position)
Time: Late Jurassic, Kimmeridgian-Tithonian epochs, ~150 mya
Location: Tendaguru Formation, Tanzania
World-famous as the tallest animal ever mounted in a museum, the east African Giraffatitan brancai
was for many years considered a species of Brachiosaurus [link]
, not least by the German paleontologists who discovered and prepared it. However since Greg Paul's 1988 paper, doubts lingered as to whether two animals separated by scores of skeletal differences and hundreds of miles of land and water even in Jurassic times, could really be from the same genus. Dr. Michael P. Taylor set the record straight in 2009, separating the African animal from Brachiosaurus
, and reaffirming the tentative separation proposed by Paul two decades earlier. Giraffatitan
was not only different from true Brachiosaurus
, it was also equally different from all other known brachiosaurs.
That said, the family resemblance is still strong. Yet Giraffatitan
is a more extreme animal, with a shorter torso, longer neck, and even longer arms than the long-armed Brachiosaurus
itself. It was also probably a bit lighter. The mounted skeleton in Berlin is primarily based on HMN SII, a teenage specimen around 75 ft. long and 33 tons as opposed to the 37 ton B. altithorax
type specimen (which coincidentally was also a teenager). Both animals likely grew 15% bigger as adults, as evidenced by a large Giraffatitan
fibula, HMN XV2.
The Humboldt Museum in Berlin houses all of the known Giraffatitan
material, which comprises multiple individuals of many growth stages, including skull material from three specimens. Though none of the Giraffatitan
specimens is complete, this taxon is far better represented in the fossil record than Brachiosaurus
, and the many overlapping remains allow for a very accurate skeletal rendition. This reconstruction was done using the nearly complete neck of the paralectotype HMN SII, without including any of the proportionally shorter HMN SI material which is typically frankensteined onto it by Greg Paul and others. The end result is a naturally
longer neck than has often been depicted.Giraffatitan
shared the tropical coastal conifer forests of Tendaguru with other endemic plant-eaters like the stegosaur Kentrosaurus
, the small diplodocoid Dicraeosaurus
, the bipedal Dryosaurus
, the barosaurine Tornieria
, the diplodocid Australodocus
, the putative camarasaur Tendaguria
, fellow brachiosaur "The Archbishop" (which had an even longer neck!) and the mysterious "first titanosaur", Janenschia
. Predators in the area included large allosaurs and ceratosaurs, and the odd small theropod Elaphrosaurus.
*Note: No GSP! Everything in this restoration was based directly on as much original data from Werner Janensch's description papers as possible, without using Greg Paul's skeletals. Indeed, with the shoulders drawn and scaled correctly, the incline of the backbone turned out considerably steeper than Paul ever envisioned it, making a vertical neck posture far less of a stretch than previously thought, pardon the pun
. Many Thanks to Mike Taylor of SV-POW for posting photos of the bones and scans of Janensch's original engravings online, and including them in his 2009 paper. References
Janensch, W. (1914). "Übersicht über der Wirbeltierfauna der Tendaguru-Schichten nebst einer kurzen Charakterisierung der neu aufgeführten Arten von Sauropoden." Archiv für Biontologie
, 3 (1): 81–110.
Janensch, W. (1922). "Das Handskelett von Gigantosaurus robustus
und Brachiosaurus brancai
aus den Tendaguru-Schichten Deutsch-Ostafrikas". Centralblatt für Mineralogie, Geologie und Paläontologie
Janensch, W. (1950a). "Die Skelettrekonstruktion von Brachiosaurus brancai
, Supplement 7 (I, 3):97-103.
Janensch, W. (1950c). "Die Wirbelsäule von Brachiosaurus brancai
, Supplement, 7:27-93.
Paul, G.S. (1988). "The brachiosaur giants of the Morrison and Tendaguru with a description of a new subgenus, Giraffatitan
, and a comparison of the world's largest dinosaurs". Hunteria
, 2(3): 1–14. (Yes I have read the paper, and no, I did not copy Paul's skeletal - which is anatomically flawed in several ways.)
Taylor, M.P. (2009). "A Re-evaluation of Brachiosaurus altithorax
Riggs 1903 (Dinosauria, Sauropod) and its generic separation from Giraffatitan brancai
(Janensch 1914)." Journal of Vertebrate Paleontology
, 29(3): 787-806. [link]