Scientists have discovered that the serrated edges of Komodo dragons' teeth are tipped with iron. The study gives new insight into how Komodo dragons keep their teeth razor-sharp and may provide clues to how dinosaurs like Tyrannosaurus rex killed and ate their prey.

A study looks at the maximum possible sizes of dinosaurs, using the carnivore, Tyrannosaurus rex, as an example. Using computer modelling, experts produced estimates that T. Rex might have been 70% heavier than what the fossil evidence suggests.