Scientists have worked out the body weight of the world's most complete Stegosaurus.
The animal is one of the instantly recognisable dinosaurs thanks to a row of sharp bony plates along its spine.
The skeleton on display at London's Natural History Museum is 80% complete.
Palaeontologists have now found the dinosaur, nicknamed 'Sophie the Stegosaurus', would have weighed about 1.6 tonnes.
'Sophie' had all her bones scanned into a computer, so scientists could work out how much weight each bone could have carried.
This would have made it similar in size to a small rhino.
But then the specimen may have been aged just six or seven when she died.
Had she survived into adulthood, the beast would have been much bigger.