|Portuguese Man of War off Looe, Cornwall|
The extraordinary symbiosis of the Man-of-War doesn't end quite yet however. It also harbours within its tentacles symbiotic fish, called - rather unimaginatively - the ‘Man-of-War Fish', that feeds from scraps of the Man-of-War’s food and eats part of the siphonophore's body! However, in return the fish acts as live bait to attract other fish. Other animals also use the Man of War for their own defence, Nudibranch Molluscs for example eat Man-of-Wars to use the Nematocysts in their own body to stop predators. The Man of War challenges simple ideas of what a organism is, giving rise to lots of questions which make us wonder whether any organism is truly separate from the rest of life.
Sadly the appearance of these marvellous wonders is less than marvellous - their continual reappearance on Cornwall's shores is a warning sign of the changes warming waters will have on our coastal ecosystems.
1) Clarke, E., 2010. The problem of biological individuality. https://link.springer.com/content/pdf/
2) Extraordinary Animals:https://www.marefa.org/images/e/ea/Piper_Extraordinary_Animals-An_Encyclopedia