The Portuguese Man O’ War
That’s an interesting-looking jellyfish, right? Wrong. Well, not about it being interesting. It is. But as you may know, the Portuguese man o’ war isn’t a jellyfish. It’s not even a single living creature.
As a whole, each specimen has no brain, eyes or heart. They can’t swim, and so are carried by the ocean currents and tides, made buoyant by the air-filed bladder which resembles the “man-of-war” sailing ship. Although they’re most often found in warmer climates, their drifting nature means that they can be found anywhere in the open ocean.
They sometimes wash up on beaches in huge numbers due to the water gathering them together: encountering one of them will very often mean encountering lots of them, and by “lots” that means possibly a group of over a thousand. That said, they can also be either “right-handed” or “left-handed”, meaning that the sail can be one of two shapes and thus send them sailing from the wind in one of two different directions.
So, what are they? They belong to the same phylum as jellyfish (the phylum “cnidaria”, pronounced with a silent c if you need to go undercover amongst marine biologists), although there are only two species in the family.
The difference is that they instead belong to the order called “siphonophora”. All siphonophores are actually a colony of different animals (zooids), but they coexist so well that they’re unable to survive on their own. This can be compared to multicellular organisms (like humans and other large animals): our bodies are made up of millions of similarly specialised individual cells, and so we may have at some point back in our evolution been in a similar biological situation.
Back to the present: Portuguese men o’ war are made up of four different animals: the floaty one, the digesty ones, the sexy ones and the stingy ones. Or, if you’re still undercover at that marine biologist party, the pneumatophore (sail), the gastrozooids, the gonozoids and the dactylzooids.
The floaty one is a polyp which makes up the bladder, and looks a bit like a bottle or a Cornish pasty, depending on where you’re from. The man o’ war is able to inflate or deflate this bladder, which allows it to submerge if it comes under attack. Otherwise, it just (literally) goes with the flow.
The digesty ones have little mouths which surround and digest food, which the tentacles of the stingy ones drag the food close to, and the sexy ones are responsible for reproduction.
How can just one-quarter of the creature can be responsible for the reproduction of all of it? Despite their name, Portuguese men o’ war can be either male or female, and they release sperm or eggs into the water accordingly. The larvae which are produced can then divide asexually to produce the different types of animals which make up the adult creature, in much the same way as a fertilised egg can divide and form many different types of cells.
The tentacles are the most infamous part of these creatures, and rightly so: they are an average of 10m (30ft) long, and secrete a neurotoxin which is about 75% the potency of cobra venom. The pain usually lasts about an hour, with long red welts left on the skin for a couple of days. However, although a sting is painful, it won’t kill a human, excepting the possibility of allergies. And if the venom gets in your lymph nodes it can be especially painful, and fever or shock are a possibility. Up to ten thousand people are stung a year just in Australia (of course they’re commonly found there, what did you expect?), where they’re known as “bluebottles”, but deaths are incredibly rare. Unless of course you’re a small fish, larvae or another of the man o’ war’s natural prey.
Unlike jellyfish stings, vinegar is not a recommended treatment and may in fact make the pain worse by helping the nematocysts (thread-like stings found on the tentacles, fired at the prey) deliver more venom. Peeing on somebody’s sting is also not recommended, unless you’re into that sort of thing or deliberately trying to lose friends.
The best thing to do is rinse off with salt water, and then apply either hot water (to denature the toxins) or aspirin to create a paste. The pain should subside, but medical advice is recommended if it gets worse or if the person goes into shock.
Even dead specimens can deliver a sting if they’re not dried out, so it’s best to keep your distance, unless you’re in the mood for some abstract photography.
7:42 pm • 25 November 2013 • 18 notes