The diet of some animals is not what the shape of their teeth would have you think. That’s the conclusion from a recent study on the jaw of a wedgefish by a team headed by Mason Dean, scientist at the Max Planck Institute of Colloids and Interfaces in Potsdam-Golm. Although these batoid fish, i.e. relatives of sharks and rays, have wide teeth and normally eat shellfish and shrimp, fragments of tail spines in their jaws reveal that they also hunt stingrays. This suggests that, in the future, zoologists and may need to look harder for evidence of animals’ dietary habits and behaviours, as they may not be immediately apparent.