Dolphins beat up octopuses before eating them, and the reason is kind of horrifying…
Generally speaking, it’s best if your food doesn’t kill you. This isn’t usually a problem in the animal kingdom, as prey tends to be dead and limp by the time it hits the gullet. But not all creatures are harmless after death: consider the octopus.
Octopus arms remain deadly for a while after they’ve been detached from the head. And we’re not talking just little spasms that might choke you up. The octopus nervous system isn’t centralized the same way ours is, so when you chop off its tentacles you’re not severing all the ties to the brain. Two thirds of its neurons are in the arms, and the octopus uses those neurons to try to escape whatever is trying to eat it. Even after it’s dead. So if you’re a dolphin trying to eat a tasty, slimy octopus for dinner (and who would blame you?), you should definitely incapacitate it first.
Dolphins who don’t properly handle their tentacled meals may end up dead themselves. One male dolphin was found with an octopus head in its stomach but a detached, 1.3 meter-long arm stretching up its throat and out its mouth. Another didn’t even manage to swallow the whole octopus, instead dying with the cephalopod stuck in its mouth. Dinner shouldn’t end with asphyxiation, so dolphins have learned another trick: chuck it around before you chow down.
Read it all and learn something, like do not eat raw live octopi! HERE