Is the Portuguese man o' war a single animal?
The Portuguese man o' war resembles a jellyfish but is a floating siphonophore colony made of specialized zooids.
Body plan, feeding and the marine environment
A gas-filled float keeps the colony at the surface and wind drives its movement. Different zooids perform feeding, defense, digestion and reproduction and cannot live as complete animals alone. Stinging capsules on long tentacles paralyze fish and plankton, and contractions carry prey to digestive zooids. Relationships among marine invertebrates cannot be inferred from appearance alone because similar forms can evolve in different lineages. Pressure, light, temperature, salinity and currents shape feeding and movement. Laboratory observations may not represent the full behavior seen in nature.
Ecosystem function, defense and conservation
Stranded tentacles may still sting even when they appear dry. Contact can cause severe pain and systemic reactions, so they should not be handled and local medical guidance should be followed. Winds, currents and sea temperature influence mass strandings. These animals may shape ecosystems through filtration, decomposition, sediment mixing or reef building. Warming, deoxygenation, acidification, plastic, seabed damage and overharvest are considered together. Conservation targets habitat processes as well as individual species.