Not so gigantic after all: Response to Lacovara et. al.
Lacovara et al. (2014) described a large juvenile titanosaurian sauropod dinosaur skeleton that they claimed was unusually enormous at ~60 tonnes. That mass estimate is too high by a factor of about two, and numerous other sauropods were larger, sometimes much larger, than the Dreadnoughtus holotype.
Had Lacovara et al. estimated the mass of the juvenile Dreadnoughtus from a life volume estimate based on their digitized skeletal, or even their conventional restoration when scaled to the size of the vertebrae, then they would have arrived at a much lower and more realistic tonnage.