The movie was called Jaws for a reason. The great white shark's powerful chompers make it a feared marine killing machine. However, researchers have found, it takes a while to grow into that ferociousness—adolescent great whites don't yet have strong enough jaws to complete an attack on tougher prey without harming themselves, and it takes until adulthood for that jaw strength to develop. The study by Toni Ferrara and colleagues, forthcoming in the Journal of Biomechanics, used the scanning technique called computerised tomography (CT) to take a look at the great white's developing jaw, and compare it to a relative: the sand tiger shark (also called the grey nurse shark).
With these scans, they were able to create digital three-dimensional models of the sharks' heads. The models revealed that the great white's jaws are reinforced by layers of tough "mineralised cartilage", which take years form. So until the sharks grow ...
