In South Florida these would be so abundant some years that they would wash ashore and dry up in the sun, the roasted tentacles forming a continuous brown strip for miles, mixed with smaller amounts of seaweed at the high tide point.<p>Punctuated every few feet by the intact blue balloons, which were fun for kids to step on and pop harmlessly once the dead tentacles had decayed like that.<p>Even then there were usually only a few floating around when you were out swimming in the Atlantic. It was not too difficult to avoid them, but occasionally you could get a small string of welts anyway, more likely from detached tentacles than direct contact with one.<p>But if the ocean got rough when there were significant numbers close to shore, the tentacles would break up into a million pieces and you couldn't swim without tiny little stings like pin-pricks all the time.
These are called blue bottles in Australia, and we get them fairly regularly where I live (Bondi) but also up and down the east coast. I'm sure they are on the west coast as well.<p>I had thought they were 3 distinct parts, not 5. It is a fascinating bit of symbiosis.
> And, lo and behold: they found that there were actually five species of Physalia<p>I am not sure there are different species, Wikipedia says one species and mentioned at some point some thought there might be more than one. [1]<p>An article published in New Zealand Geographic in 2002 [2] mentions multiple species a number of times but also states that Marine Biologist and taxonomist Emeritus Professor Philip Roy Pugh (RIP 2021) does not agree:<p>> Phil Pugh, an English expert on world siphonophore jellies (of which the bluebottle is one), thinks not. He believes there is only a single worldwide bluebottle species, Physalia physalis, but that it varies greatly in size.<p>Philip Pugh described a quarter of all known siphonophores [3], more than any one person. So he probably knew what he was talking about.<p>There is a tendency in certain areas of biology to attribute extremely minor regional variation to new species.<p>[1] <a href="https://en.wikipedia.org/wiki/Portuguese_man_o%27_war" rel="nofollow">https://en.wikipedia.org/wiki/Portuguese_man_o%27_war</a><p>[2] <a href="https://www.nzgeo.com/stories/summertime-blues/" rel="nofollow">https://www.nzgeo.com/stories/summertime-blues/</a><p>[3] <a href="https://noc.ac.uk/news/memoriam-philip-roy-pugh" rel="nofollow">https://noc.ac.uk/news/memoriam-philip-roy-pugh</a>
I've been stung by one of these on my foot while surfing. It was painful. Painful enough for me to get out of the water and call it a day.<p>The man in the photograph with his limb covered must have had an awful day.
We get lots of these in the Bay of Biscay for some reason. Not really warm waters, it's the North-is Atlantic. I guess it's mild in summer, that's when we get them.
I'm reminded of moss sex which is sort of like if your sperm or eggs went off and got a job an an apartment and a social life and only bothered to spin up a full-blown human being for sexy times. Both forms being multicellular and alternating (see: <a href="https://en.m.wikipedia.org/wiki/Alternation_of_generations" rel="nofollow">https://en.m.wikipedia.org/wiki/Alternation_of_generations</a>).<p>I guess that's a bit like the caterpillar and the butterfly, though I think they have the same ploidy.<p>Except for Portuguese Man-O-War, it's not an alternation but the multiple forms all existing at once. Still pretty weird but I think there's actually more precedent for this kind of thing than initially comes to mind: switch/case blocks really high up in the genomic call stack.<p>I'm a bit disappointed to learn that these "separate" animals are genetically identical. When I first heard this described I thought it was like lichen where cells from multiple kingdoms are each reproducing in tandem and forming structures that neither could make happen independently: Like if your gut biome moved out and figured out how to bootstrap enough of a body to get its own job and apartment and...
I feel doubtful about this article. They claim that the man-o-war is the largest colonial organisms, but there are HUGE siphonophores that are 100m long.
> a single Portuguese man-o’-war is composed of four or five separate animals.<p>Sorry, no. Just because they are not physically connected to each other doesn't make them separate animals. They are a single animal made of parts that happen not to be physically attached to one another. This is not uncommon in nature. Colony insects like ants and bees and termites are even more extreme examples of this. An individual ant (or bee or termite) is not an organism any more than (say) your spleen is. Most ants (or bees or termites) are sterile. They cannot reproduce. It is the <i>colony</i> that is the organism, not the individual insect.