|MadSci Network: Earth Sciences|
It is hard to know exactly how large the largest sauropods were because we only have a few examples of some of the species (with no way to tell if they were large or small compared to others of their kind) and because so many of the fossils are missing parts, particularly tails. Some of the very largest examples are estimated based on comparing the size of single, detached bones to the same bone in another, similar sauropod¸ then just scaling up . Early sauropods were small - maybe around 1.5 meters - but over time, they became larger. Some of the largest sauropods like the Supersaurus, Diplodocus, and Argentinosaurus reached 30–40 metres in length, and 30-50 tons or more in weight. Other large sauropods include Saltasaurus, Opisthocoelicauidia, Rapetosaurus, Paralititan, Bruhathkayosaurus and Amphicoelias. Based on a single 2.4 meter vertebrae, Amphicolias may have been as long as 56-62 meters. Weights for the largest sauropods are also estimates since we don’t know the exact sizes and we don’t know the exact shapes of their bodies, however, some estimates are as high as 150 tons or more. References: 1. Biggest of the Big: A critical re-evaluation of the mega-sauropod Amphicoelias fragillimus Cope, 1878, Carpenter, K., in Foster, J.R. and Lucas, S. G., eds., 2006, Paleontology and Geology of the Upper Jurassic Morrison Formation. New Mexico Museum of Natural History and Science Bulletin 36., https://scientists.dmns.org/sites/kencarpenter/PDFs%20of% 20publications/Amphicoelias.pdf 2. http://en.wikipedia.org/wiki/Sauropodomorpha 3. http://dml.cmnh.org/2004Sep/msg00086.html 4. http://news.bbc.co.uk/2/hi/science/nature/4031789.stm 5. Weischampel DB, Dodson P, Osmólska H, "The Dinosauria", University of California Press, 1990
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