They Don't Make Noise
Some people avoid cooking lobster at home because of the way that they're normally dispatched -- headfirst, live, into a pot of boiling water. Some home cooks have been horrified by sounds coming from the inside of the pot -- noises, which they believe, are the lobster screaming in pain as it dies. The thing is, lobster don't have vocal cords or any way of making noise. The sounds heard are probably air escaping from the lobster's shell. There may be a crackling noise from live lobsters as they rub their legs, together, but that's about it.
So if they're not screaming, do they feel pain at all? That's a matter of some debate. Some researchers claim that they don't because they lack a complex nervous system or brain like vertebrates do. A 2005 study by the Norwegian Scientific Committee for Food Safety concluded that any violent reaction by the lobster to being cooked is a reflexive response to an unpleasant stimuli, called nociception -- not the same thing as pain and suffering. But a 2013 study conducted at Queen's University Belfast in the U.K. had the opposite conclusion [source: Cressey]. The jury's still out, so if you love to eat lobster but want to know it's being prepared in the most humane way possible, seek out restaurants that use a CrustaStun, a machine that quickly kills lobster and other crustaceans via electrocution.