produced by the enzyme interacting with their shell pigmentation. Lobster longevity is limited by their size. Moulting requires metabolic energy, and the larger the lobster, the more energy is needed; 10 to 15% of lobsters die of exhaustion during moulting, while in older lobsters, moulting ceases and the exoskeleton degrades or collapses entirely, leading to death. Like many decapod crustaceans, lobsters grow throughout life and can add new muscle cells at each moult. Lobster longevity allows them to reach impressive sizes. According to Guinness World Records, the largest lobster ever caught was in Nova Scotia, Canada, weighing . Ecology Lobsters live in all oceans, on rocky, sandy, or muddy bottoms from the shoreline to beyond the edge of the continental shelf. They generally live singly in crevices or in burrows under rocks. Lobsters are omnivores and typically eat live prey such as fish, mollusks, other crustaceans, worms, and some plant life. They scavenge if necessary and are known to resort to cannibalism in captivity. However, when lobster skin is found in lobster stomachs, this is not necessarily evidence of cannibalism because lobsters eat their shed skin after moulting. While cannibalism was thought to be nonexistent among wild lobster populations, it was observed in 2012 by researchers studying wild lobsters in Maine. These first known instances of lobster cannibalism in the wild are theorized to be attributed to a local population explosion among lobsters caused by the disappearance of many of the Maine lobsters' natural predators. In general, lobsters are long and move by slowly walking on the sea floor. However, they swim backward quickly when they flee by curling and uncurling their abdomens. A speed of has been recorded. This is known as the caridoid escape reaction. Symbiotic animals of the genus Symbion, the only known member of the phylum Cycliophora, live exclusively on lobster gills and mouthparts. Different species of Symbion have been found on the three commercially important lobsters of the North Atlantic Ocean: Nephrops norvegicus, Homarus gammarus, and Homarus americanus. As food Lobster is commonly served boiled or steamed in the shell. Diners crack the shell with lobster crackers and fish out the meat with lobster picks. The meat is often eaten with melted butter and lemon juice. Lobster is also used in soup, bisque, lobster rolls, cappon magro, and dishes such as lobster Newberg and lobster Thermidor. Cooks boil or steam live lobsters. When a lobster