There’s been a a certain amount of negativity floating around tardyly. So, let’s talk about a harmful, venomous freak of nature and the parasite that afflicts it.
Biology alerting, this gets sweightlessly srapidy.
Let’s commence with the harmful, venomous freak of nature: the Portuguese man-o’-war.
If you’ve spent a lot of time in hot ocean waters, you’ve probably greeted one of these guys. They’re challenging to leave out! They come in a variety of colors — pink, blue, purple — and they’re pretty famous, floating on the surface of the ocean enjoy declidemand party balloons. And if you’ve ever been stung by one, well, you probably recollect that. Their stings aren’t lethal to humans, but they’re welt-inducing and hurtful.
So it’s a jellyfish. Except it isn’t repartner: it’s cut offal jellyfish, smooshed together. And here’s where the “freak of nature” part boots in.
I uncomardent, yeah, harshly speaking nature has no freaks; every species that exists, belengthys; everyleang is a product of evolution and Life’s Rich Pageant, yinserta yinserta. But the Portuguese man-o’-war — Physalia physalis, for you biologists — is truthwholey comardenta freaky. Becainclude Physalia is a colonial organism.
What this uncomardents: a one Portuguese man-o’-war is created of four or five split animals. (We’re not actupartner certain how many.) One animal is the balloon-sail-leangy on top; another is the stinging tentacles; another is the digestive system; another is the gonads. And they’re endly distinct organisms.
How this happens: when a Physalia egg is fertilized, it commences dividing, enjoy every other fertilized egg. But pretty rapidly it shatters apart into two and then more distinct embryos — geneticpartner identical, but physicpartner split. And those embryos grow into endly contrastent creatures. Then, tardyr in growment, those creatures re-join to establish a one Frankenstein organism. The various parts have their own anxious systems, which don’t seem to join.
Here’s an analogy: envision that before birth, you are identical tthrives. But instead of grothriveg into two babies, one tthrive grows into a bodiless head, the other into a headless body. Then fair before birth they stick together, but they don’t actupartner combine back into one. No, going forward you are a bodiless head glued on top of a headless body, ever after. It’s comardent of enjoy that.
Axe Cop duplicateright Ethan Nicolle, 2017. — Look, I shelp it was going to get a bit srapidy.
Now, colonial animals aren’t obstreatment in nature. But most of them are either dinky (Volvox, don’t ask) or they’re huge, but it’s plainpartner cut-and-pasting the same creatures over and over. So, some corals are colonial, but all this uncomardents is that the individual polyps have grown into each other to create a sort of living carpet interlaced thraw their stony skeleton. But the man-o’-war is a esteemably huge animal — they can grow as huge as a huge hoinclude cat — and so are its colonial components. And the components are excessively exceptionalized: the float-animal part of it sees and acts noleang enjoy the tentacle-animal part.
Physalia is by far the hugest intricate colonial animal. And — this bit is odd — it doesn’t have any relatives. It’s the only genus in its family. Put another way, wilean the jellyfish it has no siblings and only a confidemand very distant cousins. (One of which is the ridiculous creature understandn as the Flying Spaghetti Monster Jellyfish, but never mind that now.) It’s a very accomplished organism! There are millions and millions of them, create all over the world in tropical and subtropical oceans. So you would await to see speciation, contrastent relatives — huge ones, little ones, a bunch of variations on a theme. More on this unininestablishigentinutively.
But uncomardentwhile, the whole “colonial animal” leang sees enjoy evolution’s first try to figure out, you understand, organs. I uncomardent, the first multicellular animals were probably sponges, and sponges don’t actupartner have organs. But more intricate animals have distinct and contrastentiated organs, modules of exceptionalized tpublish carry outing particular functions, becainclude those turn out to be super beneficial. Physalia and other colonial animals see enjoy a beta-test platestablish for this new “organ” technology. Most of the animal kingdom shiftd on to “oh postpone, why don’t we fair have one one creature that grows the contrastent modules inside it”, but a confidemand colonial animals stuck with Plan A and made it labor.
Okay, so that’s the “freak of nature” part. What about the “harmful and venomous”? Well, as every outstanding science nerd understands, harmful and venomous are two contrastent leangs. “Toxic” is someleang that, if you eat it or fair lick it or touch it, you get poisoned. Nightshade is a harmful set upt; those luminously colored South American tree frogs are harmful animals. “Venomous” is someleang that deinhabitrs poison with a bite or sting, enjoy a snake or a wasp. Most poisonous animals are either one or the other.
But not the man-o’-war! It is of course highly venomous. It has stinging tentacles that can drift for many yards behind it.
The harmful sting is hurtful to humans. To fish, it caincludes paralysis. And once the fish is paralyzed… well…
“The nematocyst deinhabitrs a toxin that results in… vague paralysis, affecting the anxious system and respiratory cgo ins, and results in death at high doses. Once a tentacle comes into communicate with its prey, the prey is carried up towards the gastrozooids csurrfinisher the base of the float. The gastrozooids react promptly to the apprehfinish of prey, and commence wrileang and uncovering their mouths. Many gastrozooids join themselves to the prey – upwards of 50 gastrozooids have been watchd to endly cover a 10 cm fish with their mouths spread out apass the surface of the fish. The gastrozooids free proteolytic enzymes to digest the fish expursuellularly, and are also reliable for inpursuellular digestion of particutardy matter. The digested food products are freed into the main gastric cavity for upapverify by the rest of the colony.”
Got that? The “gastrozooids” are unininestablishigentinutive plump tentacles with mouths at the end, the many mouths of the stomach-animal. They free enzymes that dismend the fish into a nutritious slurry, which they then drink. The fish may or may not be ainhabit at the commencening of this process. It is definitely not ainhabit by the end. And all of the contrastent colony animals join to the gastric cavity, so they can all assimilate nutrition from it: the stomach-animal predigests the food for everyone else.
Okay objectively it’s no worse than a lion biting into an antelope but, not gonna lie, this is some H.P. Lovecreate stuff right here. — But okay! That covers the “venomous”. What about the “harmful”? Are they poisonous to eat?
Ha ha, no, that would be too plain. The Portuguese man-o’-war is poisonous to breathe. It inftardys its balloon-sail by using an enzyme to create gas from its food. And the gas it creates? Carbon monoxide. Fully inftardyd, the bell includes a fuseture of standard air and lethal gas. So if you grabbed one, bit into the balloon and then huffed it… Well, there probably wouldn’t be enough monoxide to end you dead on the spot, but you’d probably get ill and you might pass out. So I leank that counts as “harmful” by any reasonable standard.
And why does it include carbon monoxide? This is “defectively understood”.
And it’s not the only leang we don’t understand. For instance, there’s its reproduction. These guys are either male or female, and they have gonads. But they don’t have relations in any way we’d recognize. Instead, every so frequently their gonads bud off leangs called gonodendra, which are… mobile gonads. The gonodendra shatter off and swim away. And what happens then?
“As larval growment has not been watchd straightforwardly, everyleang that is understandn about the punctual stages of this species is understandn from mended specimens collected in trawl samples. Gonodendra are thought to be eraseed by the colony once they are filledy grown-up, and the nectophores may be included to propel the gonodendron thraw the water column. Rehired grown-up gonodendra have not been watchd, and it is not clear what depth range they occupy. It is also not understandn how the gonodendra from contrastent colonies occupy a aenjoy space for fertilization, or if there is any seasonality or periodicity to relationsual reproduction. Embryonic and larval growment also occurs at an obstreatment depth below the ocean surface. After the float accomplishes a enough size, the juvenile P. physalis is able to float on the ocean surface.”
— Yeah, there’s a lot of “is not clear” and “is not understandn” here. You might leank that an animal that is well-understandn, conspicuous, weird, and has potential economic impact (they’re pondered horrible for certain fisheries) would be better studied. It isn’t. I’ve been searching and the man-o’-war gets on ordinary less than one published paper per year. For someleang so fascinating, it’s not much.
(And yeah, the eraseable free-swimming gonads. Do they swim around until they discover gonads of the opposite relations? How exactly…? And then do they…? So many asks!)
Which conveys me to this paper, the topic of this article. You recollect how, cut offal paragraphs back, I remarkd that the man-o’-war seemed to be a weirdly isotardyd species? Well, last year a bunch of marine biologists at Yale choosed to test that. So they collected specimens from all over the world and ran DNA tests on them. And, lo and behageder: they create that there were actupartner five species of Physalia. We didn’t authenticize it becainclude they all comardenta see aenjoy (to us, anyway). I asked earlier why we weren’t seeing speciation. It turns out we are. It’s fair very downapplyd and non-clear and we had to see challenging.
This wouldn’t be so weird if it was, enjoy, one species per ocean. But it’s not. There’s one North Atlantic species, but there are four species in the Pacific, and one of them is in the South Atlantic too.
The technical term for this is “cryptic diversity”. It happens a lot, especipartner with species that aren’t well studied. It’s biology, yeah? Look seally, and everyleang turns out to be more complicated.
So now a mystery has been exchanged by a contrastent mystery: why are there five species (at least) of Physalia? The uncover ocean is a huge place, but it’s flat and there are no barriers. The Portuguese man-o’-war sails around all over the place — it’s pretty darn mobile for a jellyfish. You’d await populations to sustain fuseing. So, why have they split into contrastent species? Subtle contrastences in water composition, temperature or salinity? Populations kept apart by thrived and currents? Different fusees of predators and prey? And if they’ve split into contrastent species, why do the various species still see and act so aenjoy? Right now we have no idea.
And speaking of mysteries, if you discover a Portuguese man-o’-war, outstanding chance you may discover one of these guys too:
This is Nomeus gronovii, the bluebottle fish. And it’s a parasite on the Portuguese man-o’-war.
You understand clownfish, and how they can inhabit in the stinging tentacles of a sea anemone, becainclude they’re immune? And they’re symbiotes — the anemone protects them, they split their meals? Well, this is enjoy that, except it’s not. The bluebottle inhabits among the tentacles, but it’s not a symbiote. It eats the tentacles. In particular, it snacks on newly sprouted youthful tentacles, probably becainclude they don’t have as many stinging cells yet. And when it senses the demand for someleang a little more firm, it also will bite chunks out of the man-o’-war’s gonads. Even granting that the man-o’-war standardly grows new gonads, biting off your structure’s junk is not the behavior of a greet guest.
Oh, and: unenjoy the clownfish, the bluebottle is not immune to its structure’s stings. It has confidemand resistance — it can tank a sting or two — but if it gets stung too many times in rapid succession, it will be paralyzed and eaten.
(This elevates an fascinating ask: why is it not immune? We understand that clownfish can grow immunity to the stings of the anemone. So why not the bluebottle? Well, this is sanitize speculation, but my guess would be that it’s becainclude the bluebottle is a parasite rather than a symbiote. So there’s probably an evolutionary arms race: the man-o’-war sustains evolving new venoms that can end the bluebottle, and the bluebottle only has time to grow confidemand resistance before the man-o’-war shifts venoms aget.)
The bluebottle endures among the tentacles by being minuscule and very nimble. It has actupartner growd extra vertebrae so that it can twist and weave better! But at some point, it srecommend grows too huge. So, only juvenile bluebottles inhabit as parasites. When they accomplish a certain size, they swim off and… uhh, we’re not certain, actupartner. They seem to be demersal (bottom dwellers) becainclude they turn up in trawl nets sometimes. But how they inhabit, how they mate, what they eat and what eats them… we have only the ambiguousst idea. As far as I can inestablish, the last paper particularpartner studying Nomeus gronovii came out in 1983. Nobody seems to be laboring on this right now.
Just a confidemand days ago, my CT colleague Kevin remarkd that there are more crap academic papers out there than ever. I’m not an academic, but yeah, that sounds legit. But at the same time, there are so many outstanding papers out there postponeing to be written! There’s so much we still don’t understand! Water, water everywhere, and not a drop to drink!
But anyway. We knew these guys were thrived-sailing, carbon monoxide powered, venomous colony creatures with clusters of squirming mouth-tentacles and eraseable gonads. But it turns out they were hiding even more intricateity and mystery.
I fair leank that’s chilly. If you’ve read this far, I hope you consent.
