Titanosaur
Titanosaurs hold the world record for the size of a land animal.  One place in the Argentine had 150 bones from seven titanosaurs.  The largest were from an animal 40 metres (~130 feet) long and 20 metres (35 feet) tall. It would have weighed about 77 tonnes. A local farm worker stumbled on the remains in the desert near La Flecha, about 250km (135 miles) west of Trelew, Patagonia. The BBC flew a team out to record the event. David Attenborough follows the story of how experts found the world's largest dinosaur measuring 121ft  and its heart weighed more than three people.