Seafood is any form of sea life regarded as food by humans, prominently
including fish and shellfish. Shellfish include various species of
molluscs (e.g., bivalve molluscs such as clams, oysters, and mussels,
and cephalopods such as octopus and squid), crustaceans (e.g. shrimp,
crabs, and lobster), and echinoderms (e.g. sea cucumbers and sea
urchins). Historically, marine mammals such as cetaceans (whales and
dolphins) as well as seals have been eaten as food, though that happens
to a lesser extent in modern times. Edible sea plants such as some
seaweeds and microalgae are widely eaten as sea vegetables around the
world, especially in Asia.
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