All Hands On Deck!

The Portuguese Man-of-War, also known as a Bluebottle, is not one organism, but instead a colony of hydrozoan animals called Zooids. 


Members of the colony have distinct roles. One individual forms the float (visible above the water), which is filled with a mixture of nitrogen, carbon monoxide and even argon. Individual called gastrozooids are responsible for digesting food and passing it to the rest of the colony. Prey is captured by dactylozooids, which comprises a large stinging tentacle. Reproduction is carried out by gonozooids. Since the Portuguese man of war has no means of propulsion, it is moved by a combination of winds, currents, and tides. It normally inhabits warm tropical and sub-tropical waters.

The stinging, venom-filled nematocysts in the tentacles can paralyze small fish and other prey. Detached tentacles and dead specimens (including those that wash up on shore) can sting just as painfully as the live organism in the water and may remain potent for hours or even days after the death of the organism or the detachment of the tentacle. Stings usually cause severe pain to humans, leaving whip-like, red welts on the skin that normally last two or three days after the initial sting, though the pain should subside after about an hour.

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