durophagy

thumb|right|Jaws and teeth of Rhinoptera bonasus (cownose ray) Durophagy is the eating behavior of animals that consume hard-shelled or exoskeleton-bearing organisms, such as corals, shelled mollusks, or crabs. It is mostly used to describe fish, but is also used when describing reptiles, including fossil turtles, placodonts, some mosasaurs and extinct crocodylians, invertebrates, as well as "bone-crushing" mammalian carnivores such as hyenas. Durophagy requires special adaptions, such as blunt, strong teeth and a heavy jaw. Bite force is necessary to overcome the physical constraints of consuming more durable prey and gain a competitive advantage over other organisms by gaining access to more diverse or exclusive food resources earlier in life. Those with greater bite forces require less time to consume certain prey items as a greater bite force can increase the net rate of energy intake when foraging and enhance fitness in durophagous species.

In the order Carnivora there are two dietary categories of durophagy; bonecrackers and bamboo eaters. Bonecrackers are exemplified by hyenas and borophagines, while bamboo eaters are primarily the giant panda and the red panda. Both have developed similar cranial morphology. However, the mandible morphology reveals more about their dietary resources. Both have a raised and dome-like anterior cranium, enlarged areas for the attachment of masticatory muscles, enlarged premolars, and reinforced tooth enamel. Bamboo eaters tend to have larger mandibles, while bonecrackers have more sophisticated premolars.