# How does the Portuguese Man o' War work? (Zooids and colonial organisms) **URL:** \ **Category:** Factual Questions\ **Created:** [July 16, 2025, 4:41pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925 "2025-07-16T16:41:20Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [July 16, 2025, 4:41pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/1 "2025-07-16T16:41:20Z")
The Man o’ War is sometimes thought of by the layperson as a jellyfish, but it’s not. It’s a colonial organism called a siphonophore. It consists of zooids that are each specialized, but come from the same fertilized egg and have the same DNA. That much I get from reading stuff. But how are zooids different than human cells or organs? We also have cells and structures that are specialized for various purposes, but we don’t consider ourselves to be colonial organisms. The zooids can’t survive autonomously, at least to the best of my limited understanding (the only biology class I had was in the 9th grade). I’m trying to wrap my head around what “colonial organism” really means. ---
**Author:** ![Elmer\_J.Fudd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/elmer_j.fudd/32/1211_2.png) [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)\ **Post date:** [July 16, 2025, 6:12pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/2 "2025-07-16T18:12:39Z")
Perhaps the difference is that zooids are created embryonically (meiosis) rather than through cellular division (mitosis). It would be like your lungs birthing another lung (I think). ---
**Author:** ![eburacum45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eburacum45/32/8690_2.png) [@eburacum45](https://boards.straightdope.com/u/eburacum45)\ **Post date:** [July 16, 2025, 6:17pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/3 "2025-07-16T18:17:41Z")
In a Portuguese man 'o War, the zooids are all genetically identical, so surely it can’t be meiosis, or they’d all be slightly different. ---
**Author:** ![Elmer\_J.Fudd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/elmer_j.fudd/32/1211_2.png) [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)\ **Post date:** [July 16, 2025, 6:19pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/4 "2025-07-16T18:19:40Z")
Not if the eggs and sperm are contributed by zooids with the same DNA. (This is me spitballing with more confidence than I actually have in my conclusions) ---
**Author:** ![eburacum45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eburacum45/32/8690_2.png) [@eburacum45](https://boards.straightdope.com/u/eburacum45)\ **Post date:** [July 16, 2025, 6:20pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/5 "2025-07-16T18:20:43Z")
Self-fertilisation, eh? ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [July 16, 2025, 8:00pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/6 "2025-07-16T20:00:13Z")
> [@CookingWithGas](#): > > We also have cells and structures that are specialized for various purposes, but we don’t consider ourselves to be colonial organisms. Zooids may be highly specialized like organs, but they are derived from whole organisms, not cells. or think of it like this: - In a _colonial organism_, the parts are made of _modified individuals_. - In a _multicellular organism_, the parts are made of _modified cells_. Colonies form not from a zygote developing into organs, but from asexual reproduction producing multiple organism-like modules that then specialize and integrate. Livers never lived as independent organisms. (side note : we’ll leave aside the next level of endosymbiotic cell organelles like mitochondria as outside the current problem) There are also edge cases, like slime moulds, which shift from one to another. > [@CookingWithGas](#): > > The zooids can’t survive autonomously Zooids of some hydrozoan cnidarians (“snail fur”) can survive and regenerate new whole organisms. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [July 16, 2025, 8:14pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/7 "2025-07-16T20:14:36Z")
Then again, there are a number of species where some small fragment of an organism can survive and grow an entire new organism. I suspect that the real answer is just that biology is messy, and it’s not always possible to draw clear boundaries as to what counts as “the same organism”, and the boundaries aren’t necessarily even drawn in the same fuzzy places for different cases. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [July 16, 2025, 8:39pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/8 "2025-07-16T20:39:45Z")
> [@Chronos](#): > > Then again, there are a number of species where some small fragment of an organism can survive and grow an entire new organism. Sure - either where specialized stem cells do it (like in flatworms) or where some surviving segments can do it. Not many where one single organ can regrow the whole thing, though. In _Hydractinia echinata_, a gastrozooid can regenerate into a whole new colony. That’s like your stomach having the ability to grow a whole new you. ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [July 16, 2025, 9:31pm UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/9 "2025-07-16T21:31:32Z")
Zooids are multicellular animals, so the parts also have parts. They’re cnidarians like jellyfish and coral, just that both morphotypes (medusae and polyps, respectively) are simultaneously present in the same organism. PMo’W are made up of zooids who are all male or all female in the colony, and they reproduce sexually with [gonophores](https://en.wikipedia.org/wiki/Gonophore) and use asexual budding to build the rest of the colony. They’re essentially all clones within the colony, mutations aside. The weirder thing for me is lichen, which consists of colonies of two different kingdoms, cyanobacteria and fungi. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [July 17, 2025, 12:14am UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/10 "2025-07-17T00:14:30Z")
> [@MrDibble](#): > > Sure - either where specialized stem cells do it (like in flatworms) or where some surviving segments can do it. Not many where one single organ can regrow the whole thing, though. In _Hydractinia echinata_, a gastrozooid can regenerate into a whole new colony. That’s like your stomach having the ability to grow a whole new you. In addition, zooidal organisms have no specialized circulatory systems to deliver either nutrients or oxygen, and to remove waste products. These are moved by diffusion from the speciality organ-like autozooids for feeding, digestion, and excretion. As noted, any collection of zooidal cells can reproduce the entire colonial organism, and for most zooidal organisms can reproduce by budding or division but they can also reproduce both asexually and sexually through dedicated reproductive systems. Zooidal animals are highly diverse and many species exhibit polymorphism (ability to grow into or convert to different forms). The Portuguese Man O’ War (_Physalia physalis_) is a pretty sophisticated siphonophore, capable of sexual reproduction and active, nervous-like rapid response to environmental stimuli despite being a colonial organism, but if you cut one up into many small pieces of a few cells each and kept it in a nutrient solution it would be able to regrow into the entire differentiated colonial organism. Stranger ---
**Author:** ![Kropotkin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kropotkin/32/18045_2.png) [@Kropotkin](https://boards.straightdope.com/u/Kropotkin)\ **Post date:** [July 17, 2025, 12:25am UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/11 "2025-07-17T00:25:17Z")
> [@Stranger\_On\_A\_Train](#): > > if you cut one up into many small pieces of a few cells each and kept it in a nutrient solution it would be able to regrow into the entire differentiated colonial organism. That!s just wrong, by which I mean creepy. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [July 17, 2025, 12:45am UTC](https://boards.straightdope.com/t/how-does-the-portuguese-man-o-war-work-zooids-and-colonial-organisms/1020925/12 "2025-07-17T00:45:19Z")
[![](https://giffiles.alphacoders.com/182/182137.gif) ](https://giffiles.alphacoders.com/182/182137.gif) Who’s creepy? Not a little head that detatches from the body, grows spider-legs and a prehensile tongue! I’m crawin’ here! Stranger