Patagotitan

A giant titanosaur from Patagonia that shows how dinosaur records shrink under scrutiny. When it was named in 2017, its describers estimated about 37 meters and 69 tons and suggested it outsized Argentinosaurus. A revised scaling method in 2020 slimmed it to around 57 tons, and its full length remains uncertain because no complete skeleton is known. Its value here is the comparison. Depending on the method, the two titanosaurs now sit in a near tie, with Argentinosaurus often estimated slightly heavier. Either way, the largest dinosaurs reached roughly a third to half the mass of the biggest blue whales.