View source for Portuguese man o' war

{{Short description|Marine invertebrate}}
{{About|the marine invertebrate|other uses|Man o' war (disambiguation){{!}}Man o' war}}
{{Speciesbox
| image = Portuguese Man-O-War (Physalia physalis).jpg
| taxon = Physalia physalis
| authority = ([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])
| parent_authority = [[Jean-Baptiste Lamarck|Lamarck]], 1801<ref>{{cite book |last1=Lamarck |first1=J. B. |author-link=Jean-Baptiste Lamarck |year=1801 |title=Système des animaux sans vertèbres |url=https://www.biodiversitylibrary.org/page/14117719#page/381/mode/1up |location=Paris, France |publisher=by the author and Deterville |pages=355–356 |via=[[Biodiversity Heritage Library]] |access-date=2023-06-07 |archive-date=2023-06-07 |archive-url=https://web.archive.org/web/20230607045937/https://www.biodiversitylibrary.org/page/14117719#page/381/mode/1up |url-status=live }}</ref>
| grandparent_authority = [[Johann Friedrich von Brandt|Brandt]], 1835<ref>{{cite journal |last=Brandt |first=Johann Friedrich |date=1834–1835 |title=Prodromus descriptionis animalium ab H. Mertensio in orbis terrarum circumnavigatione observatorum. Fascic. I., Polypos, Acalephas Discophoras et Siphonophoras, nec non Echinodermata continens |url=https://www.biodiversitylibrary.org/page/10765514#page/40/mode/1up |journal=Recueil Actes des séances publiques de l'Acadadémie impériale des Science de St. Pétersbourg 1834 |pages=201–275 |via=[[Biodiversity Heritage Library]] |access-date=2023-06-07 |archive-date=2023-06-07 |archive-url=https://web.archive.org/web/20230607045937/https://www.biodiversitylibrary.org/page/10765514#page/40/mode/1up |url-status=live }}</ref>{{rp|236–238}}
| display_parents = 3
| synonyms =
{{hidden begin}}
* Family-level synonym<ref>{{cite web |last=Schuchert |first=P. |year=2019 |title=Physaliidae Brandt, 1835 |url=http://www.marinespecies.org/aphia.php?p=taxdetails&id=135342 |website=World Register of Marine Species |publisher= Flanders Marine Institute |archive-url=https://web.archive.org/web/20181027162645/http://www.marinespecies.org/aphia.php?p=taxdetails&id=135342 |archive-date=27 October 2018 |access-date=11 March 2019}}</ref>
** Physalidae <small>[[Johann Friedrich von Brandt|Brandt]], 1835</small> (original spelling)
* Genus-level synonyms<ref>{{cite web |last=Schuchert |first=P. |year=2019 |title=''Physalia'' Lamarck, 1801. |url=http://www.marinespecies.org/aphia.php?p=taxdetails&id=135382 |website=World Register of Marine Species |publisher= Flanders Marine Institute |archive-url=https://web.archive.org/web/20160314223746/http://www.marinespecies.org/aphia.php?p=taxdetails&id=135382 |archive-date=14 March 2016 |access-date=11 March 2019}}</ref>
**''Arethusa'' <small>[[Lorenz Oken|Oken]], 1815</small>
**''Holothuria'' <small>[[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]]</small>
**''Physalis'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physsophora'' <small>[[Adolph Modéer|Modéer]], 1789</small>
*Species-level synonyms<ref name=WoRMSPhysaliaphysalis>{{cite web |last=Schuchert |first=P. |year=2019 |title= ''Physalia physalis'' (Linnaeus, 1758) |url=http://www.marinespecies.org/aphia.php?p=taxdetails&id=135479 |website=World Register of Marine Species |publisher= Flanders Marine Institute |archive-url=https://web.archive.org/web/20180727155003/http://www.marinespecies.org/aphia.php?p=taxdetails&id=135479 |archive-date=27 July 2018 |access-date=11 March 2019}}</ref>
**''Arethusa caravell'' <small>[[Lorenz Oken|Oken]], 1815</small>
**''[[Holothuria]] velificans'' <small>[[Pehr Osbeck|Osbeck]], 1765</small>
**''[[Medusa utriculus]]'' <small>[[Johann Friedrich Gmelin|Gmelin]], 1788</small>
**''Physalia australis'' <small>[[François Péron|Péron]], 1807</small>
**''Physalia gigantea'' <small>[[Jean Baptiste Bory de Saint-Vincent|Bory de St Vincent]], 1894</small>
**''Physalia glauca'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalia megalista'' <small>[[Charles Alexandre Lesueur|Lesueur]] & [[Nicolas-Martin Petit|Petit]]</small>
**''Physalia pelagica'' <small>[[Jean-Baptiste Lamarck|Lamarck]], 1801</small>
**''Physalia pelasgica'' <small>[[Louis Augustin Guillaume Bosc|Bosc]], 1802</small>
**''Physalia utriculus'' <small>[[Johann Friedrich Gmelin|Gmelin]], 1788</small>
**''Physalis afer'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis arethusa'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis cornuta'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis elongata'' <small>[[Jean-Baptiste Lamarck|Lamarck]], 1816</small>
**''Physalis glauca'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis lamartinieri'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis megalista'' <small>[[Jean-Baptiste Lamarck|Lamarck]], 1816</small>
**''Physalis osbeckii'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis pelagica'' <small>[[Wilhelm Gottlieb Tilesius von Tilenau|Tilesius]], 1810</small>
**''Physalis pelagica'' <small>[[Jean-Baptiste Lamarck|Lamarck]], 1816</small>
**''Physalis tuberculosa'' <small>[[Jean-Baptiste Lamarck|Lamarck]], 1816</small>
**''Physsophora physalis'' <small>[[Adolph Modéer|Modéer]], 1789</small>
{{hidden end}}
| synonyms_ref =
}}
The '''Portuguese {{not a typo|man o'}} war''' ('''''Physalia physalis'''''), also known as the '''man-of-war'''<ref name=oed>{{OED|Portuguese man-of-war}}</ref> or '''bluebottle''',<ref>{{Cite web |last= |first= |title=Bluebottle |url=https://australian.museum/learn/animals/jellyfish/bluebottle/ |access-date=2024-01-23 |website=The Australian Museum |language=en}}</ref> is a marine [[hydrozoa]]n found in the [[Atlantic Ocean]] and the [[Indian Ocean]]. It is considered to be the same species as the '''Pacific man o' war''' or '''bluebottle''', which is found mainly in the [[Pacific Ocean]].<ref>{{cite web |url=http://museum.wa.gov.au/research/research-areas/aquatic-zoology/resources/sea-stinger-factsheets/bluebottles |title=Bluebottle factsheet |publisher=Western Australian Museum |access-date=12 August 2015 |archive-url=https://web.archive.org/web/20150321011427/http://museum.wa.gov.au/research/research-areas/aquatic-zoology/resources/sea-stinger-factsheets/bluebottles |archive-date=21 March 2015}}</ref> The Portuguese man o' war is the only species in the genus '''''Physalia''''', which in turn is the only genus in the family '''Physaliidae'''.<ref>{{Cite web |title=WoRMS - World Register of Marine Species - Physalia Lamarck, 1801 |url=https://www.marinespecies.org/aphia.php?p=taxdetails&id=135382 |access-date=2021-10-24 |website=www.marinespecies.org |archive-date=2022-01-12 |archive-url=https://web.archive.org/web/20220112042505/https://www.marinespecies.org/aphia.php?p=taxdetails&id=135382 |url-status=live }}</ref>
The Portuguese man o' war is a conspicuous member of the [[neuston]], the community of organisms that live at the surface of the ocean. It has numerous microscopic venomous [[cnidocyte]]s which deliver a painful sting powerful enough to kill fish, and even, in some cases, humans. Although it superficially resembles a [[jellyfish]], the Portuguese man o' war is in fact a [[Siphonophorae|siphonophore]]. Like all siphonophores, it is a [[Colony (biology)|colonial organism]], made up of many smaller units called [[zooid]]s.<ref name=Munro2019 /> Although they are [[Morphology (biology)|morphologically]] quite different, all of the zooids in a single specimen are [[Clonal colony|genetically identical]]. These different types of zooids fulfill specialized functions, such as hunting, digestion and reproduction, and together they allow the colony to operate as a single individual.
==Etymology==
[[File:Caravela de armada of Joao Serrao.jpg|thumb|The name comes from the animal’s resemblance to a sailing warship, the Portuguese man-of-war (the [[caravel]])]]
The name ''man o’ war'' comes from the [[man-of-war]], a sailing warship,<ref name=Greene1998>{{cite book|last1=Greene|first1=Thomas F.|title=Marine Science: Marine Biology and Oceanography|publisher=Amsco School Publications|location=|year=1998|isbn=978-0-87720-071-0}}</ref> and the animal's resemblance to the Portuguese version (the [[caravel]]) at full sail.<ref name=WoRMSPhysaliaphysalis/><ref name=oed/><ref name=Millward2012>{{Cite news|url=https://www.telegraph.co.uk/earth/earthnews/9526551/Surge-in-number-of-men-owar-being-washed-up-on-beaches.html|title=Surge in number of men o'war being washed up on beaches|last=Millward|first=David|date=8 September 2012|work=[[The Daily Telegraph]]|archive-url=https://web.archive.org/web/20121031062706/https://www.telegraph.co.uk/earth/earthnews/9526551/Surge-in-number-of-men-owar-being-washed-up-on-beaches.html|archive-date=2012-10-31|access-date=2012-09-07|url-status=dead}}</ref>
==Taxonomy==
The bluebottle, Pacific man o' war or Indo-Pacific Portuguese man o' war, distinguished by a smaller float and a single long fishing [[Tentacle#Cnidarians_and_ctenophores|tentacle]], was originally considered a separate [[species]] in the same [[genus]] (''P. utriculus''). The name was synonymized with ''P. physalis'' in 2007, and it is now considered a regional form of the same species.<ref name=Bardi2007>{{cite journal|last1=Bardi|first1=Juliana|last2=Marques|first2=Antonio C.|title=Taxonomic redescription of the Portuguese man-of-war, Physalia physalis (Cnidaria, Hydrozoa, Siphonophorae, Cystonectae) from Brazil|journal=Iheringia. Série Zoologia|volume=97|issue=4|pages=425–433|year=2007|doi=10.1590/S0073-47212007000400011}}</ref><ref>{{cite WoRMS |author=Schuchert, P. |year=2022 |title=World Hydrozoa Database. Physalia utriculus (Gmelin, 1788) |id=387269 |accessdate=1 March 2022}}</ref>
==Coloniality==
The man o' war is described as a [[Colony (biology)|colonial organism]] because the individual [[zooid]]s in a colony are evolutionarily derived from either [[Polyp (zoology)|polyps]] or [[medusae]],<ref name=Dunn>{{cite web|last1=Dunn|first1=Casey|title=Colonial organization|url=http://www.siphonophores.org/SiphOrganization.php|website=Siphonophores|access-date=27 February 2024}}</ref> i.e. the two basic body plans of [[cnidaria]]ns.<ref name=Mahalski>{{cite web|title=Polyp and medusa body shapes|url=https://teara.govt.nz/en/diagram/4721/polyp-and-medusa-body-shapes|website=Te Ara, the Encyclopedia of New Zealand|publisher=Manatū Taonga/Ministry for Culture and Heritage, Wellington, New Zealand|access-date=27 February 2024|last1=Mahalski|first1=Bruce}}</ref> Both of these body plans comprise entire individuals in non-colonial cnidarians (for example, a [[jellyfish]] is a medusa, while a [[sea anemone]] is a polyp). All zooids in a man o' war develop from the same single fertilized egg and are therefore genetically identical. They remain physiologically connected throughout life, and essentially function as organs in a shared body. Hence, a Portuguese man o' war constitutes a single organism from an [[ecology|ecological]] perspective, but is made up of many [[Clone (cell biology)|individuals]] from an [[Embryology|embryological]] perspective.<ref name=Dunn/>
Most species of [[Siphonophorae|siphonophores]] are fragile and difficult to collect intact.<ref>{{cite journal |doi = 10.1080/10635150500354837|title = Molecular Phylogenetics of the Siphonophora (Cnidaria), with Implications for the Evolution of Functional Specialization|year = 2005|last1 = Dunn|first1 = Casey W.|last2 = Pugh|first2 = Philip R.|last3 = Haddock|first3 = Steven H. D.|journal = Systematic Biology|volume = 54|issue = 6|pages = 916–935|pmid = 16338764}}</ref><ref>{{cite book |doi = 10.1016/S0065-2881(08)60074-7|title = Siphonophore Biology|series = Advances in Marine Biology|year = 1988|last1 = MacKie|first1 = G.O.|last2 = Pugh|first2 = P.R.|last3 = Purcell|first3 = J.E.|volume = 24|pages = 97–262|isbn = 9780120261246}}</ref> However, ''P. physalis'' is the most accessible, conspicuous, and robust of the siphonophores, and much has been written about this species.<ref name=Wittenberg1960/><ref>{{cite journal |doi = 10.1007/s12526-015-0417-6|title = On the distribution of Physalia physalis (Hydrozoa: Physaliidae) in Chile|year = 2016|last1 = Araya|first1 = Juan Francisco|last2 = Aliaga|first2 = Juan Antonio|last3 = Araya|first3 = Marta Esther|journal = Marine Biodiversity|volume = 46|issue = 3|pages = 731–735| bibcode=2016MarBd..46..731A |s2cid = 2646975}}</ref><ref>{{cite journal|doi = 10.2307/1539711|jstor = 1539711|title = Fine Structures of the Carbon Monoxide Secreting Tissue in the Float of Portuguese Man-of-War (Physalia physalis L.)|last1 = Copeland|first1 = D. Eugene|journal = Biological Bulletin|year = 1968|volume = 135|issue = 3|pages = 486–500|url = https://www.biodiversitylibrary.org/part/13168|access-date = 2021-12-15|archive-date = 2021-12-15|archive-url = https://web.archive.org/web/20211215074254/https://www.biodiversitylibrary.org/part/13168|url-status = live}}</ref><ref>{{cite journal |doi = 10.1016/0305-0491(71)90099-X|title = Biliprotein coloration of Physalia physalis|year = 1971|last1 = Herring|first1 = Peter J.|journal = Comparative Biochemistry and Physiology Part B: Comparative Biochemistry|volume = 39|issue = 4|pages = 739–746}}</ref><ref>{{cite journal |doi = 10.1111/j.1749-6632.1960.tb26418.x|title = The Toxin of Physalia Nematocysts|year = 2006|last1 = Lane|first1 = Charles E.|journal = Annals of the New York Academy of Sciences|volume = 90|issue = 3|pages = 742–750|pmid = 13758711|s2cid = 44654850}}</ref><ref>{{cite journal |doi = 10.1002/jcp.1030600106|title = Float gases, gas secretion and tissue respiration in the Portuguese man-of-war,Physalia|year = 1962|last1 = Larimer|first1 = James L.|last2 = Ashby|first2 = Ebert A.|journal = Journal of Cellular and Comparative Physiology|volume = 60|pages = 41–47}}</ref><ref>{{cite journal |doi = 10.1038/177290b0 |title = Dimorphism in the Portuguese Man-of-War |year = 1956 |last1 = Totton |first1 = A. K. |last2 = MacKie |first2 = G. O. |journal = Nature |volume = 177 |issue = 4502 |page = 290 |bibcode = 1956Natur.177..290T |s2cid = 4296257}}</ref><ref>{{cite journal|doi = 10.1017/s0025315400014156|title = The Portuguese Man-of-War, Physalia Physalis L., in British and Adjacent Seas|year = 1947|last1 = Wilson|first1 = Douglas P.|journal = Journal of the Marine Biological Association of the United Kingdom|volume = 27|issue = 1|pages = 139–172|pmid = 18919646| bibcode=1947JMBUK..27..139W |s2cid = 28767812|url = http://plymsea.ac.uk/1269/1/The_Portuguese_Man-Of-War%2C_Physalia_physalis_L.%2C_in_British_and_adjacent_seas.pdf|access-date = 2021-12-15|archive-date = 2018-07-20|archive-url = https://web.archive.org/web/20180720092010/http://plymsea.ac.uk/1269/1/The_Portuguese_Man-Of-War,_Physalia_physalis_L.,_in_British_and_adjacent_seas.pdf|url-status = live}}</ref><ref>{{cite journal |doi = 10.1042/bj0850009|title = Folic acid derivatives in the gas gland of Physalia physalis L|year = 1962|last1 = Wittenberg|first1 = JB|last2 = Noronha|first2 = JM|last3 = Silverman|first3 = M.|journal = Biochemical Journal|volume = 85| issue=1 |pages = 9–15|pmid = 14001411|pmc = 1243904}}</ref><ref name=Yanag2002>{{cite journal|last1=Yanagihara|first1=Angel A.|last2=Kuroiwa|first2=Janelle M.Y.|last3=Oliver|first3=Louise M.|last4=Kunkel|first4=Dennis D.|title=The ultrastructure of nematocysts from the fishing tentacle of the Hawaiian bluebottle, Physalia utriculus (Cnidaria, Hydrozoa, Siphonophora)|journal=Hydrobiologia|volume=489|issue=1–3|pages=139–150|year=2002|url=http://www5.pbrc.hawaii.edu/pcrl/pdf/ultrastructure_physalia_Hydrobiologia.pdf|doi=10.1023/A:1023272519668|s2cid=603421}}</ref>{{excessive citations inline|date=April 2022}} The development, morphology, and colony organization of ''P. physalis'' is very different from that of other siphonophores.<ref name=Munro2019/> Its structure, embryological development, and [[histology]] have been examined by several authors.<ref name=Bardi2007/><ref>Mackie, G. O. (1960) "Studies on Physalia physalis (L.). Part 2. Behavior and histology". ''Discovery Reports''. '''30''': 371–407.</ref><ref>Okada, Y. K. (1932) "Développement post-embryonnaire de la Physalie Pacifique". ''Mem. Coll. Sci. Kyoto Imp. Univ., Ser. B, Biol'', '''8''': 1–27.</ref><ref>Totton, A. K. (1960) "Studies on Physalia physalis (L.). Part 1. Natural history and morphology". ''Discovery Reports'', '''30''': 301–368.</ref> These studies provide an important foundation for understanding the morphology, cellular anatomy, and development of this  species.
==Description==
[[File:Anatomy of a Physalia physalis colony.png|thumb|upright=1.3|Anatomy, with descriptions of the function of each type of zooid<ref name=Munro2019/>]]
Like all siphonophores, ''P. physalis'' is a colonial organism: each animal is composed of many smaller units ([[zooid]]s) that hang in clusters from under a large, gas-filled structure called the pneumatophore.<ref name=ADW>{{cite web|title=''Physalia physalis'', Portuguese man-of-war|url=https://animaldiversity.org/accounts/Physalia_physalis/|website=Animal Diversity Web|publisher=Museum of Zoology, University of Michigan|access-date=27 February 2024}}</ref>
Seven different types of zooids have been described in the man o' war, and all of these are interdependent on each other for survival and performing different functions, such as digestion ([https://en.wiktionary.org/wiki/gastrozooid gastrozooids]), reproduction ([[gonozooid]]s) and hunting (dactylozooids). A fourth type of zooid is the pneumatophore. Three of these types of zooids are of the [[jellyfish|medusoid]] type ([[gonophore]]s, [https://en.wiktionary.org/wiki/nectophore nectophores], and vestigial nectophores), while the remaining four are of the [[polyp (zoology)|polypoid]] type (free gastrozooids, tentacle-bearing zooids, gonozooids and gonopalpons).<ref name=Bardi2007/> However, naming and categorization of zooids varies between authors, and much of the embryonic and evolutionary relationships of zooids remains unclear.<ref name=Munro2019/>
The pneumatophore or bladder is the most conspicuous part of the man o' war. This large, gas-filled, translucent structure is pink, purple or blue in color; it is {{convert|9|to|30|cm|in|abbr=on}} long and rises as much as {{convert|15|cm|in|frac=2|abbr=on}} above the water. The pneumatophore functions as both a flotation device and a sail, allowing the animal to move with the prevailing wind.<ref name=Munro2019 /><ref name=ADW /> The gas in the pneumatophore is mostly air which diffuses in from the surrounding atmosphere, but it also contains as much as 13% [[carbon monoxide]], which is actively produced by the animal.<ref name=Wittenberg1960>{{Cite journal|last=Wittenberg|first=Jonathan B.|title=The Source of Carbon Monoxide in the Float of the Portuguese Man-of-War, ''Physalia physalis'' L|journal=Journal of Experimental Biology|volume=37|issue=4|pages=698–705|year=1960|doi=10.1242/jeb.37.4.698|url=http://jeb.biologists.org/content/jexbio/37/4/698.full.pdf}}</ref><ref name=Clark1961>{{cite journal|last1=Clark|first1=F.E.|last2=Lane|first2=C.E.|title=Composition of float gases of Physalia physalis|journal=Proceedings of the Society for Experimental Biology and Medicine|volume=107|issue=3|pages=673–674|year=1961|doi=10.3181/00379727-107-26724|pmid=13693830|s2cid=2687386}}</ref> In the event of a surface attack, the pneumatophore can be deflated, allowing the animal to temporarily submerge.<ref name="ng">{{cite web |url=https://www.nationalgeographic.com/animals/invertebrates/facts/portuguese-man-of-war |title=Portuguese Man-of-War |work=National Geographic Animals |date=11 November 2010 |publisher=[[National Geographic Society|National Geographic]] |access-date=2021-03-08 |archive-date=2021-03-06 |archive-url=https://web.archive.org/web/20210306190914/https://www.nationalgeographic.com/animals/invertebrates/facts/portuguese-man-of-war |url-status=dead }}</ref>
New zooids are added by [[budding]] as the colony grows. Long tentacles hang below the float as the animal drifts, fishing for prey to sting and drag up to its digestive zooids.<ref name=Totton1960>Totton, A. and Mackie, G. (1960) "Studies on Physalia physalis", ''Discovery Reports'', '''30''': 301–407.</ref><ref name=Lee2021/>
The colony hunts and feeds through the cooperation of two types of zooids: tentacle-bearing zooids known as dactylozooids (or palpons), and gastrozooids.<ref name=Munro2019/> The palpons are equipped with tentacles, which are typically about {{convert|10|m|ft|sigfig=1|abbr=on}} in length but can reach over {{convert|30|m|ft|sigfig=1|abbr=on}}.<ref name="Portuguese Man-of-War" /><ref>{{cite web |url=http://oceanservice.noaa.gov/facts/portuguese-man-o-war.html |title=What is a Portuguese Man o' War? |author=NOAA |work=[[National Ocean Service]] |quote=Updated 10 October 2017 |date=27 July 2015 |access-date=2016-02-08 |archive-url=https://web.archive.org/web/20160222171442/http://oceanservice.noaa.gov/facts/portuguese-man-o-war.html |archive-date=22 February 2016 |url-status=live |df=dmy-all}}</ref> Each tentacle bears tiny, coiled, thread-like structures called [[Cnidocyte|nematocysts]]. Nematocysts trigger and inject venom on contact, stinging, paralyzing, and killing [[Mollusca|molluscs]] and fishes. Large groups of Portuguese man o' war, sometimes over 1,000 individuals, may deplete fisheries.<ref name=Bardi2007/><ref name=ng /> Contraction of tentacles drags the prey upward and into range of the gastrozooids. The gastrozooids surround and digest the food by secreting [[digestive enzyme]]s. ''P. physalis'' typically has multiple stinging tentacles, but a regional form (previously known as a separate species, ''P. utriculus'') has only a single stinging tentacle.
The main reproductive zooids, the gonophores, are situated on branching structures called gonodendra. Gonophores produce sperm or eggs. Besides gonophores, each gonodendron also contains several other types of specialized zooids: gonozooids (which are accessory gastrozooids), nectophores (which have been speculated to allow detached gonodendra to swim), and vestigial nectophores (also called jelly polyps; the function of these is unclear).<ref name=Munro2019/>
==Life cycle==
[[File:Lifecycle of the Portuguese man of war.png|thumb|Lifecycle of the Portuguese man o' war.<ref name=Munro2019/> The mature animal is pictured floating on the ocean surface, while early development is thought to occur at an unknown depth below the surface of the ocean. The gonodendra are thought to be released from the colony when mature. The egg and [[planula]] larva stage have not yet been observed.]]
Man o' war individuals are [[Dioecy|dioecious]], meaning each colony is either male or female.<ref name=ADW/><ref name=Munro2019/> Gonophores producing either sperm or eggs (depending on the sex of the colony) sit on a tree-like structure called a gonodendron, which is believed to drop off from the colony during reproduction.<ref name=Munro2019/> Mating takes place primarily in the autumn, when eggs and sperm are shed from gonophores into the water.<ref name=ADW/> As neither fertilization nor early development has been directly observed in the wild, it is not yet known at what depth these occur.<ref name=Munro2019/>
A fertilized man o' war egg develops into a [[planula]] that buds off new zooids as it grows, gradually forming a new colony. This development initially occurs under the water, and has been reconstructed by comparing different stages of planulae collected at sea.<ref name=Munro2019/> The first two structures to emerge are the pneumatophore (sail) and a single, early feeding zooid called a protozooid. Later, gastrozooids and tentacle-bearing zooids are added. Eventually, the growing pneumatophore becomes buoyant enough to carry the immature colony on the surface of the water.<ref name=Munro2019/>
==Ecology==
{{see also|Ocean surface ecosystem}}
===Predators and prey===
[[File:Blue dragon-glaucus atlanticus (8599051974).jpg|thumb|The [[Glaucus atlanticus|blue dragon]] feeds on men o' war.]]
[[File:Janthina.jpg|thumb|The [[Janthina janthina|violet sea snail]] feeds on men o' war.]]
{{ external media
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| video1 = [https://www.youtube.com/watch?v=u_LU1GA6pu4 How the Portuguese man o' war stings and eats prey] {{align|right|– ''Blue Planet II''}}
}}
The Portuguese man o' war is a [[carnivore]].<ref name="Portuguese Man-of-War" /> Using its venomous tentacles, it traps and paralyzes its prey while reeling it inwards to its digestive polyps. It typically feeds on small fish, molluscs, shrimp and other small crustaceans, and [[zooplankton]].<ref>{{cite web| url=https://animaldiversity.org/accounts/Physalia_physalis/| title=Physalia physalis (Portuguese man-of-war)| website=[[Animal Diversity Web]]| access-date=2021-02-10| archive-date=2021-02-13| archive-url=https://web.archive.org/web/20210213004123/https://animaldiversity.org/accounts/Physalia_physalis/| url-status=live}}</ref>
The organism has few predators; one example is the [[loggerhead sea turtle]], which feeds on the Portuguese man o' war as a common part of its diet.<ref name=Brodie1989>{{cite book|last1=Brodie|first1=Edmund D. Jr.|title=Venomous Animals: 300 Animals in Full Color|publisher=Golden Press|location=|year=1989|isbn=978-0-307-24074-3}}</ref> The turtle's skin, including that of its tongue and throat, is too thick for the stings to penetrate. Also, the [[Glaucus atlanticus|blue sea slug]] specializes in feeding on the Portuguese man o' war,<ref name=Scocchi>{{cite web|first1=Carla|last1=Scocchi|first2=James B.|last2=Wood|url=http://www.thecephalopodpage.org/MarineInvertebrateZoology/Glaucusatlanticus.html|title=''Glaucus atlanticus'', Blue Ocean Slug|publisher=Thecephalopodpage.org|access-date=2009-12-07|archive-url=https://web.archive.org/web/20171005130631/http://www.thecephalopodpage.org/MarineInvertebrateZoology/Glaucusatlanticus.html|archive-date=2017-10-05|url-status=live}}</ref> as does the [[Janthina janthina|violet sea snail]].<ref name="M&S">{{cite book|last1=Morrison|first1=Sue|last2=Storrie|first2=Ann|title=Wonders of Western Waters: The Marine Life of South-Western Australia|year=1999|publisher=[[Department of Conservation and Land Management|CALM]]|isbn=978-0-7309-6894-8|page=68}}</ref> The [[ocean sunfish]]'s diet, once thought to consist mainly of jellyfish, has been found to include many species, including the Portuguese man o' war.<ref>{{cite journal|title=DNA barcoding identifies a cosmopolitan diet in the ocean sunfish|first1=Lara L.|last1=Sousa|first2=Raquel|last2=Xavier|first3=Vânia|last3=Costa|first4=Nicolas E.|last4=Humphries|first5=Clive|last5=Trueman|first6=Rui|last6=Rosa|first7=David W.|last7=Sims|first8=Nuno|last8=Queiroz|journal=Scientific Reports|volume=6|issue=1|page=28762|year=2016|doi=10.1038/srep28762|pmid=27373803|pmc=4931451|bibcode=2016NatSR...628762S}}</ref><ref>{{cite web|url=http://oceana.org/marine-life/corals-and-other-invertebrates/portuguese-man-o-war|title=Portuguese Man o' War|work=Oceana.org|publisher=Oceana|access-date=2017-04-02|archive-url=https://web.archive.org/web/20170403110351/http://oceana.org/marine-life/corals-and-other-invertebrates/portuguese-man-o-war|archive-date=2017-04-03|url-status=live}}</ref>
The [[man-of-war fish]], ''Nomeus gronovii'', is a [[driftfish]] native to the Atlantic, Pacific and Indian Oceans. It is notable for its ability to live within the deadly tentacles of the Portuguese man o' war, upon whose tentacles and gonads it feeds. Rather than using mucus to prevent nematocysts from firing, as is seen in some of the [[clownfish]] sheltering among sea anemones, the man-of-war fish appears to use highly agile swimming to physically avoid tentacles.<ref name=Jenkins1983>{{cite journal|last1=Jenkins|first1=Robert L.|title=Observations on the Commensal Relationship of Nomeus gronovii with Physalia physalis|journal=Copeia|volume=1983|issue=1|pages=250–252|year=1983|doi=10.2307/1444723|jstor=1444723|url=https://www.jstor.org/stable/1444723}}</ref><ref name="Purcell and Arai 2001">{{cite journal |last1=Purcell |first1=Jennifer E. |last2=Arai |first2=Mary N. |title=Interactions of pelagic cnidarians and ctenophores with fish: A review |journal=Hydrobiologia |date=2001 |volume=451 |issue=1/3 |pages=27–44 |doi=10.1023/A:1011883905394 |s2cid=31059411 |url=https://www.researchgate.net/publication/226927949 |access-date=22 October 2022 |archive-date=22 October 2022 |archive-url=https://web.archive.org/web/20221022135434/https://www.researchgate.net/publication/226927949_Interactions_of_pelagic_cnidarians_and_ctenophores_with_fish_A_review |url-status=live }} [https://archive.today/20221022134313/https://www.researchgate.net/profile/Jennifer-Purcell-2/publication/226927949_Interactions_of_pelagic_cnidarians_and_ctenophores_with_fish_A_review/links/0912f50a6c84ac054a000000/Interactions-of-pelagic-cnidarians-and-ctenophores-with-fish-A-review.pdf PDF]</ref> The fish has a very high number of [[vertebra]]e (41), which may add to its agility<ref name="Purcell and Arai 2001" /> and primarily uses its pectoral fins for swimming—a feature of fish that specialize in maneuvering tight spaces. It also has a complex skin design and at least one [[antibody]] to the man o' war's toxins.<ref name="Purcell and Arai 2001" /> Although the fish seems to be 10 times more resistant to the toxin than other fish, it can be stung by the dactylozooides (large tentacles), which it actively avoids.<ref name=Jenkins1983/> The smaller gonozooids do not seem to sting the fish and the fish is reported to frequently nibble on these tentacles.<ref name=Jenkins1983/>
===Commensalism and symbiosis===
[[File:FMIB 51424 Portuguese-Man-of-War-Fish Nomeus gronovii.jpeg|thumb|[[Nomeus gronovii|Man-of-war fish]]]]
The Portuguese man o'&nbsp;war is often found with a variety of other marine fish, including [[yellow jack]]. These fish benefit from the shelter from predators provided by the stinging tentacles, and for the Portuguese {{nowrap|man o' war}}, the presence of these species may attract other fish to eat.<ref>{{cite encyclopedia|author-link=Ross Piper|last=Piper|first=Ross|date=2007|title=Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals|publisher=[[Greenwood Press (publisher)|Greenwood Press]]}}</ref>
The [[blanket octopus]] is immune to the venom of the Portuguese man o' war. Individuals have been observed to carry broken man o' war tentacles,<ref>{{cite web|url=http://tolweb.org/tree?group=Tremoctopus&contgroup=Argonautoid_families|title=Tremoctopus|publisher=Tolweb.org|access-date=2009-12-07|archive-url=https://web.archive.org/web/20090729093740/http://tolweb.org/tree?group=Tremoctopus&contgroup=Argonautoid_families|archive-date=2009-07-29|url-status=live}}</ref> which males and immature females rip off and use for offensive and defensive purposes.<ref>{{cite journal |last1=Jones |first1=E.C. |year=1963 |title=''Tremoctopus violaceus'' uses ''Physalia'' tentacles as weapons |journal=Science |volume=139 |issue=3556 |pages=764–766 |doi=10.1126/science.139.3556.764 |pmid=17829125 |bibcode=1963Sci...139..764J|s2cid=40186769}}</ref>
==Venom==
The stinging, venom-filled nematocysts in the [[Tentacle#Cnidarians_and_ctenophores|tentacles]] of the Portuguese man o' war can paralyze small fish and other prey.<ref name=Yanag2002/> Detached tentacles and dead specimens (including those that wash up on shore) can sting just as painfully as those of the live organism in the water and may remain potent for hours or even days after the death of the organism or the detachment of the tentacle.<ref name=Auerbach1997>{{cite journal|last=Auerbach|first=Paul S.|title=Envenomations from jellyfish and related species|journal=Journal of Emergency Nursing|volume=23|issue=6|pages=555–565|year=1997|doi=10.1016/S0099-1767(97)90269-5|pmid=9460392}}</ref>
Stings usually cause severe pain to humans, lasting one to three hours. Red, whip-like welts appear on the skin that last two or three days after the sting. In some cases, the venom may travel to the [[lymph node]]s and may cause symptoms that mimic an allergic reaction, including swelling of the [[larynx]], airway blockage, cardiac distress and shortness of breath. Other symptoms may include fever, [[Shock (circulatory)|circulatory shock]] and in extreme cases, even death,<ref name=Stein1989>{{cite journal|last1=Stein|first1=Mark R.|last2=Marraccini|first2=John V.|last3=Rothschild|first3=Neal E.|last4=Burnett|first4=Joseph W.|title=Fatal Portuguese man-o'-war (''Physalia physalis'') envenomation|journal=Annals of Emergency Medicine|volume=18|issue=3|pages=312–315|year=1989|pmid=2564268|doi=10.1016/S0196-0644(89)80421-4}}</ref> although this is extremely rare. Medical attention for those exposed to large numbers of tentacles may become necessary to relieve pain or open airways if the pain becomes excruciating or lasts for more than three hours, or if breathing becomes difficult. Instances in which the stings completely surround the trunk of a young child are among those that may be fatal.<ref name="Clinchy1996">{{cite book|author=Richard A. Clinchy|title=Dive First Responder|url=https://books.google.com/books?id=rKhW53U7FtwC&pg=PA19|year=1996|publisher=Jones & Bartlett Learning|isbn=978-0-8016-7525-6|page=19|access-date=2016-11-03|archive-url=https://web.archive.org/web/20170217043550/https://books.google.com/books?id=rKhW53U7FtwC&pg=PA19|archive-date=2017-02-17|url-status=live}}</ref>
The species is responsible for up to 10,000 human stings in Australia each summer, particularly on the east coast, with some others occurring off the coast of [[South Australia]] and [[Western Australia]].<ref name="Fenner1996">{{cite journal|last1=Fenner|first1=Peter J.|first2=John A.|last2=Williamson|date=December 1996|title=Worldwide deaths and severe envenomation from jellyfish stings|journal=Medical Journal of Australia|volume=165|issue=11–12|pages=658–661|doi=10.5694/j.1326-5377.1996.tb138679.x|issn=0025-729X|quote=In Australia, particularly on the east coast, up to 10 000 stings occur each summer from the bluebottle (''Physalia'' spp.) alone, with others also from the "hair jellyfish" (''Cyanea'') and "blubber" (''Catostylus''). Common stingers in South Australia and Western Australia, include bluebottle, as well the four-tentacled [[cubozoa|cubozoa or box jellyfish]], the "jimble" (''Carybdea rastoni'')|pmid=8985452|s2cid=45032896}}</ref>
===Treatment of stings===
Stings from a Portuguese man o' war can result in severe [[dermatitis]] characterized by long, thin, open wounds that resemble those caused by a whip.<ref>{{cite web|url=http://www.medicinenet.com/image-collection/portuguese_man_of_war_sting_picture/picture.htm|title=Image Collection: Bites and Infestations: 26. Picture of Portuguese Man of War Sting|website=www.medicinenet.com|publisher=MedicineNet Inc |quote=The sting of the Portuguese man-of-war. One of the most painful effects on skin is the consequence of attack by oceanic hydrozoans known as Portuguese men-of-war, which are amazing for their size, brilliant color, and power to induce whealing. They have a small float that buoys them up and from which hang long tentacles. The wrap of these tentacles results in linear stripes, which look like whiplashes, caused not by the force of their sting but from deposition of [[proteolytic]] venom toxins, [[urticariogenic]] and irritant substances.|archive-url=https://web.archive.org/web/20180603114215/https://www.medicinenet.com/image-collection/portuguese_man_of_war_sting_picture/picture.htm |archive-date=2018-06-03 |access-date=2014-06-13}}</ref> These are not caused by any impact or cutting action, but by irritating [[Hives|urticariogenic]] substances in the tentacles.<ref name=James2006>{{cite book |last1=James |first1=William D. |last2=Berger |first2=Timothy G. |first3=Dirk M. |last3=Elston |first4=Richard B. |last4=Odom |title=Andrews' Diseases of the Skin: Clinical Dermatology |url=https://archive.org/details/andrewsdiseasess00mdwi_659 |url-access=limited |publisher=Saunders Elsevier|year=2006 |page=[https://archive.org/details/andrewsdiseasess00mdwi_659/page/n439 429] |isbn=978-0-7216-2921-6}}</ref><ref name="Bolognia">{{cite book |last1=Rapini |first1=Ronald P. |last2=Bolognia |first2=Jean L.|last3=Jorizzo|first3=Joseph L. |title=Dermatology: 2-Volume Set |publisher=Mosby |location=St. Louis |year=2007 |isbn=978-1-4160-2999-1}}</ref>
Treatment for sting pain is immersion in {{convert|45|C}} water for 20 minutes.<ref name=Loten2006>{{cite journal|last1=Loten|first1=Conrad|last2=Stokes|first2=Barrie|last3=Worsley|first3=David|last4=Seymour|first4=Jamie E.|last5=Jiang|first5=Simon|last6=Isbister|first6=Geoffrey K.|title=A randomised controlled trial of hot water (45&nbsp;°C) immersion versus ice packs for pain relief in bluebottle stings|journal=Medical Journal of Australia|volume=184|issue=7|pages=329–333|year=2006|doi=10.5694/j.1326-5377.2006.tb00265.x|pmid=16584366|s2cid=14684627|url=https://www.mja.com.au/system/files/issues/184_07_030406/lot11135_fm.pdf}}</ref> The [[cnidocyte]] found in the [[box jellyfish]] react differently than the [[nematocyst]] in the Portuguese man o' war; cnidocytes are inhibited by application of [[vinegar]], but nematocysts can discharge more venom if vinegar is applied.<ref name=Galsziou2013>{{cite journal|last1=Galsziou|first1=Paul T.|last2=Bennett|first2=John|last3=Greenberg|first3=Peter|last4=Green|first4=Sally|title=Hot water immersion for bluebottle stings|journal=Australian Family Physician|volume=42|issue=6|year=2013|url=https://www.racgp.org.au/getattachment/572969cd-e853-42a6-8392-653145b96a1b/Bluebottle-stings.aspx}}</ref>
==Distribution==
The species is found throughout the world's oceans, mainly in tropical and subtropical regions, but occasionally also in temperate regions.<ref name=Munro2019/><ref name=Lee2021/>
==Habitat==
''P. physalis'' is a member of the [[neuston]] (the floating community of organisms that live at the interface between water and air). This community is exposed to a unique set of environmental conditions including prolonged exposure to intense [[ultraviolet]] light, risk of [[desiccation]], and rough sea conditions.<ref>{{cite book | vauthors=Zaitsev Y, Liss P | veditors=Duce R | title=The sea surface and global change | chapter=Neuston of seas and oceans | publisher=Cambridge University Press | publication-place=Cambridge New York | year=1997 | isbn=978-0-521-01745-9 | oclc=847978750}}</ref> The gas-filled bladder, or pneumatophore, remains at the surface, while the remainder is submerged. The animal has no means of propulsion; it moves passively, driven by the winds, currents, and tides. Winds can drive them into bays or onto beaches. Often, finding a single Portuguese man o' war is followed by finding many others in the vicinity.<ref name="Portuguese Man-of-War">{{cite web |url=http://animals.nationalgeographic.com/animals/invertebrates/portuguese-man-of-war.html |title=Portuguese Man-of-War |publisher=[[National Geographic Society]] |access-date=2008-06-13 |archive-url=https://web.archive.org/web/20110723141326/http://animals.nationalgeographic.com/animals/invertebrates/portuguese-man-of-war.html |archive-date=2011-07-23 |url-status=dead}}</ref> The Portuguese man o' war is well known to beachgoers for the painful stings delivered by its tentacles.<ref name=Lee2021 /> Because they can sting while beached, the discovery of a man o' war washed up on a beach may lead to the closure of the beach.<ref>{{cite news |url=http://news.bbc.co.uk/2/hi/uk_news/england/7569233.stm |title=Dangerous jellyfish wash up |work=BBC News |date=2008-08-18 |access-date=2011-09-07 |archive-url=https://web.archive.org/web/20110511114304/http://news.bbc.co.uk/2/hi/uk_news/england/7569233.stm |archive-date=2011-05-11 |url-status=live}}/</ref><ref>{{cite news |url=https://www.bbc.com/news/uk-england-cornwall-41237286 |title=Man-of-war spotted along coast in Cornwall and Wales |publisher=BBC |date=12 September 2017 |access-date=20 July 2018 |archive-url=https://web.archive.org/web/20180305023459/http://www.bbc.com/news/uk-england-cornwall-41237286 |archive-date=5 March 2018 |url-status=live |df=dmy-all}}</ref>
==Drifting dynamics==
[[File:Bluebottle (Physalia physalis) sail camber.png|thumb|The bluebottle course at zero angle of attack is dependent on the sail camber.<ref name=Lee2021>{{cite journal | last1=Lee | first1=Daniel | last2=Schaeffer | first2=Amandine | last3=Groeskamp | first3=Sjoerd | title=Drifting dynamics of the bluebottle (''Physalia physalis'') | journal=Ocean Science | publisher=Copernicus GmbH | volume=17 | issue=5 | date=October 2021 | issn=1812-0792 | doi=10.5194/os-17-1341-2021 | pages=1341–1351| bibcode=2021OcSci..17.1341L | s2cid=244189437 | doi-access=free }} [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License] {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/ |date=2017-10-16 }}.</ref>]]
''P. physalis'' uses a float filled with [[carbon monoxide]] and air as a sail to travel by wind for thousands of miles, dragging behind long tentacles that deliver a deadly venomous sting to fish.<ref name=Iosilevskii2009>{{cite journal|last1=Iosilevskii|first1=G.|last2=Weihs|first2=D.|title=Hydrodynamics of sailing of the Portuguese man-of-war ''Physalia'' physalis|journal=Journal of the Royal Society Interface|volume=6|issue=36|pages=613–626|year=2009|pmid=19091687|pmc=2696138|doi=10.1098/rsif.2008.0457}}</ref> This sailing ability, combined with a painful sting and a life cycle with seasonal blooms, results in periodic mass beach strandings and occasional human envenomations, making ''P. physalis'' the most infamous of the siphonophores.<ref name=Munro2019>{{cite journal | last1=Munro | first1=Catriona | last2=Vue | first2=Zer | last3=Behringer | first3=Richard R. | last4=Dunn | first4=Casey W. | date=October 2019 | title=Morphology and development of the Portuguese man of war, Physalia physalis | journal=Scientific Reports | publisher=Springer Science and Business Media LLC | volume=9 | issue=1 | page=15522 | issn=2045-2322 | doi=10.1038/s41598-019-51842-1 | pmid=31664071 | pmc=6820529 | bibcode=2019NatSR...915522M}} [[File:CC-BY icon.svg|50px]] Material and modified material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License] {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/ |date=2017-10-16 }}.</ref> Despite being a common occurrence, the origin of the man o' war or bluebottle before reaching the coastline is not well understood, and neither is the way it drifts at the surface of the ocean.<ref name=Lee2021 />
===Left- and right-handedness===
[[File:Physalia physalis EM1B0679 (40827501481).jpg|thumb|Looking down from above a man o' war, showing its sail. Sails can be left-handed or right-handed.]]
The Portuguese man o' war is asymmetrically shaped: the zooids hang down from either the right or left side of the midline of the pneumatophore or bladder. The pneumatophore can be oriented [[Chirality|towards the left or the right]]. This phenomenon may be an adaptation that prevents an entire population from being washed on shore to die. The "left-handed" animals sail to the right of the wind, while the "right-handed" animals sail to the left. The wind will always push the two types in opposite directions, so at most half the population will be pushed towards the coast.<ref name=Totton1956>Totton, A. and Mackie, G. (1960) "Studies on Physalia physalis", ''Discovery Reports'', '''30''': 301–40.</ref><ref name=Woodcock1944>Woodcock, A. H. (1944) "A theory of surface water motion deduced from the wind-induced motion of the Physalia", ''J. Marine Res.'', '''5''': 196–205.</ref> Regional populations can have substantial differences in float size and the number of tentacles used for hunting. The regional form previously known as ''P. utriculus'' has a bladder rarely exceeding {{convert|10|cm|sigfig=1}} in length and has one long hunting tentacle that is less than {{convert|3|m|sigfig=1}} long. In comparison, the typical man o' war has a float of around {{convert|15|to|30|cm|sigfig=2}}, and several hunting tentacles that can reach {{convert|30|m|sigfig=1}} in mature colonies when fully extended.<ref name=Munro2019/><ref name=Lee2021/> When combined with the trailing action of the tentacles, this left- or right-handedness makes the colony sail sideways relative to the wind, by about 45° in either direction.<ref name=Woodcock1956>{{cite journal|last=Woodcock|first=A.H.|title=Dimorphism in the Portuguese man-of-war|journal=Nature|volume=178|issue=4527|pages=253–255|year=1956|doi=10.1038/178253a0|bibcode=1956Natur.178..253W|s2cid=4297968|url=https://www.nature.com/articles/178253a0}}</ref><ref name=Iosilevskii2009/> Colony handedness has therefore been theorized to influence man o' war migration, with left-handed or right-handed colonies potentially being more likely to drift down particular respective sea routes.<ref name=Woodcock1956/> Handedness develops early in the colony's life, while it is still living below the surface of the sea.<ref name=Munro2019/>
===Mathematical modelling===
Since they have no propulsion system, the movement of the man o' war can be modelled mathematically by calculating the forces acting on it, or by [[Advection|advecting]] virtual particles in [[Ocean general circulation model|ocean]] and [[Atmospheric circulation|atmospheric circulation models]]. Earlier studies modelled the movement of the man o' war with [[Lagrangian particle tracking]] to explain major beaching events. In 2017, Ferrer and Pastor were able to estimate the region of origin of a significant beaching event on the southeastern [[Bay of Biscay]]. They ran a Lagrangian model backwards in time, using wind velocity and a wind [[drag coefficient]] as drivers of the man o' war motion. They found that the region of origin was the [[Sargasso Sea|North Atlantic subtropical gyre]].<ref name=Ferrer2017>{{cite journal|last1=Ferrer|first1=Luis|last2=Pastor|first2=Ane|title=The Portuguese man-of-war: gone with the wind|journal=Regional Studies in Marine Science|volume=14|issue=|pages=53–62|year=2017|bibcode=2017RSMS...14...53F|doi=10.1016/j.rsma.2017.05.004}}</ref> In 2015 Prieto et al. included both the effect of the [[ocean current|surface currents]] and wind to predict the initial colony position prior to major beaching events in the Mediterranean.<ref name=Prieto2015>{{cite journal|last1=Prieto|first1=L.|last2=MacÍas|first2=D.|last3=Peliz|first3=A.|last4=Ruiz|first4=J.|title=Portuguese Man-of-War (Physalia physalis) in the Mediterranean: A permanent invasion or a casual appearance?|journal=Scientific Reports|volume=5|issue=1|page=11545|year=2015|doi=10.1038/srep11545|pmid=26108978|pmc=4480229|bibcode=2015NatSR...511545P|s2cid=8456129}}</ref> This model assumed the man o' war was advected by the surface currents, with the effect of the wind being added with a much higher wind drag coefficient of 10%. Similarly, in 2020 Headlam et al. used beaching and offshore observations to identify a region of origin, using the joint effects of surface currents and wind drag, for the largest mass man o' war beaching on the Irish coastline in over 150 years.<ref name=Headlam2020>{{cite journal |doi = 10.1016/j.ecss.2020.107033|title = Insights on the origin and drift trajectories of Portuguese man of war (Physalia physalis) over the Celtic Sea shelf area|year = 2020|last1 = Headlam|first1 = Jasmine L.|last2 = Lyons|first2 = Kieran|last3 = Kenny|first3 = Jon|last4 = Lenihan|first4 = Eamonn S.|last5 = Quigley|first5 = Declan T.G.|last6 = Helps|first6 = William|last7 = Dugon|first7 = Michel M.|last8 = Doyle|first8 = Thomas K.|journal = Estuarine, Coastal and Shelf Science|volume = 246|page = 107033|bibcode = 2020ECSS..24607033H|s2cid = 224908448}}</ref><ref name=Lee2021/>  These earlier studies used numerical models in combination with simple assumptions to calculate the drift of this species, excluding complex drifting dynamics. In 2021, Lee ''et al.'' provide a [[Parametric equation|parameterisation]] for Lagrangian modelling of the bluebottle by considering the similarities between the bluebottle and a [[Forces on sails|sailboat]]. This allowed them to compute the hydrodynamic and aerodynamic forces acting on the bluebottle and use an equilibrium condition to create a generalised model for calculating the drifting speed and course of the bluebottle under any wind and ocean current conditions.<ref name=Lee2021/>
==Gallery==
<gallery mode="packed">
File:Man-O-War.jpg|Man o' war warning sign, Hawaii
Portuguese Man O' War Miami March 2008.jpg|Portuguese man o' war, Miami Beach, Florida
Portuguese Man o' War at Palm Beach FL by Volkan Yuksel DSC05878.jpg|Portuguese man o' war, Palm Beach, Florida
File:Cores Quentes.JPG|Man o' war beached in Brazil
File:Portugiesische galeere.jpg| Portuguese man o' war washed up on a beach
File:Faja, Faial, Azoren am 26.04.2020.jpg|They are often found ashore in large groups.
</gallery>
==See also==
<!--do not include any terms already appearing in the article-->
*[[Chondrophore]]
{{clear}}
==References==
{{Reflist}}
==External links==
{{Commons category|Physalia physalis}}
{{Wikispecies|Physalia physalis}}
* [http://www.siphonophores.org/ Siphonophores.org] General information
* [https://web.archive.org/web/20170620041914/http://www.nationalgeographic.com/animals/invertebrates/p/portuguese-man-of-war/ Portuguese Man-of-War] [[National Geographic]]
* [http://lifeinthefastlane.com/2008/12/blue-bottle-sting-australia/ Bluebottle] Life In The Fast Lane
* [https://portuguesemanofwar.com/ PortugueseManOfWar.com]
* [https://www.rnz.co.nz/national/programmes/afternoons/audio/2018825720/critter-of-the-week-bluebottle-jellyfish-portuguese-man-of-war ''Physalia physalis''] discussed on [[Radio New Zealand|RNZ]] [[Critter of the Week]], 24 December 2021.
{{Portal bar|Marine life|Animals}}
{{Taxonbar|from=Q202526|from2=Q2256295|from3=Q2704401|from4=Q10349281}}
{{Authority control}}
[[Category:Physaliidae]]
[[Category:Animals described in 1758]]
[[Category:Cnidarians of the Atlantic Ocean]]
[[Category:Cnidarians of the Caribbean Sea]]
[[Category:Cnidarians of the Indian Ocean]]
[[Category:Cnidarians of the Pacific Ocean]]
[[Category:Taxa named by Carl Linnaeus]]
[[Category:Venomous animals]]