This false-colour x-ray image shows the complex coiled shell of a tun (Tonna galea), a marine gastropod that can grow up to 25 centimeters in length. The shell's spiral form allows it to grow without building an excessively long shell, which could slow down its movement. It is a carnivore, which kills or paralyses its prey by injecting it with acid through its jaw plates. This species lives in warm shallow waters off the coasts of the Atlantic and Pacific oceans, and the Mediterranean Sea.