A giant tooth unearthed in Argentina suggests dinosaurs may have grown even bigger than previously thought.
Scientists in Argentina have dug up a giant tooth belonging to a titanosaur, a group of long-necked plant eating dinosaurs which grew up to 35m long and weighed 100 tonnes or more.
However the tooth the scientists have now found is almost 32% bigger than any earlier finds.
They say this means either titanosaurs grew even bigger than they thought, or they have found the remains of a new type of titanosaur with very large teeth compared to its body size.
The findings have been published in the journal Cretaceous Research.