Amphicoelias is believed to have been the largest dinosaur ever to live. Much bigger than Argentinosaurusor even a blue whale. Being discovered in the late 1800's and with only four bones ever found, early paleontologist had little time to study the large bones because they were crumbling at a fast rate. It was twice the length of a blue whale and twice the lengh of sauropods like diplodocus . Of course, Paleontologist today would like to get their own measurement, if they can find any fosslis. Even without fossil evidence, photographic evidence left by the behemoth's discoveror, Edward Drinker Cope, has allowed paleontologist to make calculated guess estimates. It is believed to be 160 feet (48 m) long to 200 feet long(60m), and weigh at least 120 tons to 200 tons in recent estimates This size exceed any other sauropod. It could have been the biggest reptile, sauropod and dinosaur yet. It could also be the biggest animal that ever lived!