Nothing, they are dead!
Well since they are carnivores, (meat eaters) they eat pretty much all types of animals that are in their natural habitats.
Yes, they can, and do.
lemon sharks are to big and tough to get eaten by another shark
They simply do it for food, to be blunt. The same way we eat animals, I know we (well most of us humans anyway) don't eat other animals but sometimes it is just in their natural behaviour to eat...
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