{{Short description|Temporary commensalism for transport}} {{Other uses|-phoresis}} [[File:Pseudogarypus_synchrotron_Henderickx_et_al_2012.jpg|thumb|''Pseudogarypus synchrotron'' <small>Henderickx ''et al''. 2012</small> specimen in Baltic amber.<ref>{{Cite journal |last1=Harms |first1=D. |last2=Dunlop |first2=J. A. |date=2017 |title=The fossil history of pseudoscorpions (Arachnida: Pseudoscorpiones) |journal=Fossil Record |volume=20 |issue=2 |page=223 |doi=10.5194/fr-20-215-2017|doi-access=free }}</ref>]][[File:Male_Bombus_hypnorum_male_with_phoretic_mites,_Botevgrad,_Bulgaria_02.jpg|thumb|Male ''Bombus hypnorum'' with phoretic mites. Botevgrad, Bulgaria.]] [[File:Leptopeza.flavipes.with.Lamprochernes.2.jpg|thumb|Pseudoscorpion hitching a ride on a fly]] [[File:Phoresy_edited.png|thumb|A pseudoscorpion on the leg of a crane fly]]
'''Phoresis''' or '''phoresy''' is a temporary commensalistic relationship when an organism (a phoront or phoretic) attaches itself to a host organism solely for travel.<ref name=":0">{{Cite journal|last1=White|first1=P. Signe|last2=Morran|first2=Levi|last3=de Roode|first3=Jacobus|date=June 19, 2017|title=Phoresy|url= |journal=Current Biology|volume=27|issue=12|pages=R578–R580|doi=10.1016/j.cub.2017.03.073|pmid=28633022|pmc=5749251}}</ref> It has been seen in ticks and mites since the 18th century,<ref name=":1" /> and in fossils 320 million years old.<ref name=":0" /> It is not restricted to arthropods or animals; plants with seeds that disperse by attaching themselves to animals are also considered to be phoretic.<ref name=":2">{{Citation|last=Houck|first=Marilyn A.|title=Phoresy|date=2009|url=https://linkinghub.elsevier.com/retrieve/pii/B9780123741448002058|journal=Encyclopedia of Insects|pages=772–774|publisher=Elsevier|doi=10.1016/b978-0-12-374144-8.00205-8|isbn=978-0-12-374144-8|access-date=2018-10-14|url-access=subscription}}</ref>
''Phoresis'' is rooted in the Greek words ''phoras'' (bearing) and ''phor'' (thief).<ref name=":1">{{Cite journal|last1=Houck|first1=M A|last2=OConnor|first2=B M|date=1991|title=Ecological and Evolutionary Significance of Phoresy in the Astigmata|journal=Annual Review of Entomology|volume=36|issue=1|pages=611–636|doi=10.1146/annurev.en.36.010191.003143|issn=0066-4170}}</ref> The term, originally defined in 1896 as a relationship in which the host acts as a vehicle for its passenger, clashed with other terminology being developed at the time, so constraints on the length of time, feeding, and ontogeny are now considered.<ref name=":1" /> Phoresis is used as a strategy for dispersal,<ref name=":62">{{Cite journal|last1=Zeh|first1=David W.|last2=Zeh|first2=Jeanne A.|date=1992|title=On the Function of Harlequin Beetle-Riding in the Pseudoscorpion, Cordylochernes scorpioides (Pseudoscorpionida: Chernetidae)|journal=The Journal of Arachnology|volume=20|issue=1|pages=47–51|jstor=3705790}}</ref><ref name=":3">{{Cite journal|last=Binns|first=E. S.|date=1982|title=Phoresy as migration--some functional aspects of phoresy in mites [Insect dispersion]|journal=Biological Reviews of the Cambridge Philosophical Society|volume=57|issue=4|pages=571–620|doi=10.1111/j.1469-185X.1982.tb00374.x|s2cid=84639744}}</ref> seasonal migration,<ref name=":4">{{Cite journal|last1=Liu|first1=Sai|last2=Li|first2=Jianling|last3=Guo|first3=Kun|last4=Qiao|first4=Haili|last5=Xu|first5=Rong|last6=Chen|first6=Jianmin|last7=Xu|first7=Changqing|last8=Chen|first8=Jun|date=2016-05-06|title=Seasonal phoresy as an overwintering strategy of a phytophagous mite|journal=Scientific Reports|language=En|volume=6|issue=1|article-number=25483|doi=10.1038/srep25483|issn=2045-2322|pmc=4858688|pmid=27150196|bibcode=2016NatSR...625483L}}</ref> transport to new host/habitat,<ref name=":82">{{Cite journal|last1=Saul-Gershenz|first1=Leslie S.|last2=Millar|first2=Jocelyn G.|date=2006|title=Phoretic Nest Parasites Use Sexual Deception to Obtain Transport to Their Host's Nest|journal=Proceedings of the National Academy of Sciences of the United States of America|volume=103|issue=38|pages=14039–14044|jstor=30051982|doi=10.1073/pnas.0603901103|pmid=16966608|pmc=1599908|bibcode=2006PNAS..10314039S|doi-access=free}}</ref> escaping ephemeral habitats,<ref name=":52">{{Cite journal|last1=Sabagh|first1=Leandro T.|last2=Dias|first2=Roberto Júnio P.|last3=Branco|first3=Christina W. C.|last4=Rocha|first4=Carlos F. D.|date=2011-04-28|title=News records of phoresy and hyperphoresy among treefrogs, ostracods, and ciliates in bromeliad of Atlantic forest|journal=Biodiversity and Conservation|language=en|volume=20|issue=8|pages=1837–1841|doi=10.1007/s10531-011-0050-z|s2cid=12658034|issn=0960-3115}}</ref><ref name=":1" /> and reducing inbreeding depression.<ref name=":92">{{Cite journal|last1=Schwarz|first1=H.H.|last2=Huck|first2=K.|date=1997-11-01|title=Phoretic mites use flowers to transfer between foraging bumblebees|journal=Insectes Sociaux|language=en|volume=44|issue=4|pages=303–310|doi=10.1007/s000400050051|s2cid=36137431|issn=0020-1812}}</ref> In addition to the benefits afforded to individuals and species, its presence can add to the ecological diversity and complexity of an ecosystem.<ref name=":2" />
==Mutualism, parasitism, and predation== The strict definition of phoresis excludes cases in which the relationship is permanent (e.g. that of a barnacle surviving on a whale), or those in which the phoront gains any kind of advantage from the host organism (e.g. remoras attaching to sharks for transportation and food).<ref name=":1" /> Phoresis is a commensal relationship, and deviations result in mutualistic or parasitic relationships. Phoretic relationships can become parasitic if a cost is inflicted upon the host, such as if the number of mites on a host begins impeding its movement. Parasitic relationships could also be selected from phoretic ones if the phoront gains a fitness advantage from the death of a host (e.g. nutrition). Mutualistic relationships could also develop if the phoront begins to confer a benefit to the host (e.g. predator defense).<ref name=":0" /> The evolutionary plasticity of phoretic relationships allow them to potentially add to the complexity and diversity of ecosystems.<ref name=":2" />
Cases in which the phoront parasitizes or preys upon the host organism after travel are still considered phoresis, as long as the travel behaviour and the feeding or parasitizing behaviour are separate.<ref name=":0" /> As an example, some pseudoscorpions prey upon the same species that act as their phoretic host, but The behaviours are completely separate: the pseudoscorpion utilizes anatomical features used specifically for predation when treating the host as prey, but employs anatomical features used for phoresis when travelling.<ref name=":7">{{Cite journal|last1=Poinar Jr.|first1=George O.|last2=Curcic|first2=Bozidar P. M.|last3=Cokendolpher|first3=James C.|date=1998|title=Arthropod Phoresy Involving Pseudoscorpions in the Past and Present.|journal=Acta Arachnologica|language=en|volume=47|issue=2|pages=79–96|doi=10.2476/asjaa.47.79|issn=0001-5202|doi-access=free}}</ref>
==Examples== Examples may be found in the arthropods associated with sloths. Coprophagous sloth moths, such as ''Bradipodicola hahneli'' and ''Cryptoses choloepi'', are unusual in that they exclusively inhabit the fur of sloths, mammals found in Central and South America.<ref>{{cite web |url=http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/10046/terra2008Spring.pdf;jsessionid=B178230AA02D37492C9794327FB8DB71?sequence=1 |title="An OSU scientist braves an uncharted rainforest in a search for rare and endangered species" in "Expedition to the Edge" |author=Sherman, Lee |work=Terra, Spring 2008 |publisher=Oregon State University |access-date=14 February 2011 |archive-date=3 March 2016 |archive-url=https://web.archive.org/web/20160303232053/http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/10046/terra2008Spring.pdf;jsessionid=B178230AA02D37492C9794327FB8DB71?sequence=1 |url-status=dead }}</ref><ref>{{cite journal |last1=Rau |first1=P |year=1941 |title=Observations on certain lepidopterous and hymenopterous parasites of Polistes wasps |journal=Annals of the Entomological Society of America |volume=34 |issue= 2|pages=355–366(12) |doi= 10.1093/aesa/34.2.355}}</ref> The sloth provides transport for the moths, the females of which oviposit in the droppings of sloths, which the larvae feed on. The newly eclosed moths move into the forest canopy in search of a new sloth host.
Larvae of the blister beetle (''Meloe franciscanus)'' need to find the nests of their host, the solitary bee (''Habropoda pallida''), to continue their life cycle. The larvae gather in colonies, and emit chemicals that mimic the pheromones of the female solitary bee''.'' Larvae attach to the attracted males when they visit the false source of pheromones, and then subsequently to any female the male mates with. The blister beetle larvae then infest and parasitize the female bee's nest.<ref name=":82"/>
Some species of Bromeliad treefrog (''Scinax littoreus'' and ''Scinax perpusillus)'' carry ostracods (''Elpidium'' sp.), which in turn carry ciliates (''Lagenophrys'' sp.) from one bromeliad plant to another. The plants act as ecological islands to the ostracods, and phoresis allows them to disperse over a wider area than would be available to them otherwise. The term for a phoretic organism riding on another phoretic organism is hyperphoresis.<ref name=":52"/><ref>{{Cite journal|last1=Sabagh|first1=Leandro T.|last2=Rocha|first2=Carlos F. D.|date=2014-05-06|title=Bromeliad treefrogs as phoretic hosts of ostracods|journal=Naturwissenschaften|volume=101|issue=6|pages=493–497|doi=10.1007/s00114-014-1178-y|pmid=24796544|issn=0028-1042|bibcode=2014NW....101..493S|s2cid=7825145}}</ref> [[File:Ontogeny Chaetodactylus krombeini.jpg|thumb|The phoretic deutonymph of the bee mite ''Chaetodactylus krombeini'' shows distinct morphological adaptations for phoresy relative to other parts of its life cycle. ]] Some mites in the clade Astigmatina have a stage of their life cycle (the deutonymph or hypopus) that is modified specifically for phoresis. This stage has reduced mouthparts, a well-sclerotised body that resists desiccation, and usually a posteroventral organ for attaching to the host animal (which may be an invertebrate or a vertebrate). Astigmatans often live in patchy and ephemeral habitats such as fungal fruiting bodies, dung, carrion, animal nests, tree sap flows and decaying wood. Phoresis allows these mites to quickly leave a depleted habitat and travel to a new one.<ref>{{Cite journal |last1=Klimov |first1=Pavel B. |last2=Vorontsov |first2=Dmitry D. |last3=Azar |first3=Dany |last4=Sidorchuk |first4=Ekaterina A. |last5=Braig |first5=Henk R. |last6=Khaustov |first6=Alexander A. |last7=Tolstikov |first7=Andrey V. |date=2021-07-23 |title=A transitional fossil mite (Astigmata: Levantoglyphidae fam. n.) from the early Cretaceous suggests gradual evolution of phoresy-related metamorphosis |journal=Scientific Reports |language=en |volume=11 |issue=1 |page=15113 |doi=10.1038/s41598-021-94367-2 |issn=2045-2322 |pmc=8302706 |pmid=34301989}}</ref> A specific example are the deutonymphs of ''Lardoglyphus'' dispersing on beetles in the genus ''Dermestes'' to reach new habitats (both phoront and host feed on animal materials).<ref>{{Cite journal |last=Iverson |first=Kurt |last2=Oconnor |first2=Barry M. |last3=Ochoa |first3=Ronald |last4=Heckmann |first4=Richard |date=1996-07-01 |title=Lardoglyphus zacheri (Acari: Lardoglyphidae), a Pest of Museum Dermestid Colonies, with Observations on Its Natural Ecology and Distribution |url=https://academic.oup.com/aesa/article-lookup/doi/10.1093/aesa/89.4.544 |journal=Annals of the Entomological Society of America |language=en |volume=89 |issue=4 |pages=544–549 |doi=10.1093/aesa/89.4.544 |issn=1938-2901|url-access=subscription }}</ref>
A specialist mite (''Parasitellus fucorum)'' that parasitizes bumble bees (''Bombus'' spp.) avoids inbreeding depression in a single hive, and remains genetically independent of any specific host lineage by travelling to a new hive. This is accomplished by travelling on a foraging bee to a flower and detaching, and waiting for and attaching to another bee which may be from another hive, and infesting the new hive. These mites can survive on flowers for up to 24 hours, and have shown a preference for opened flowers, where they would be most likely to find a host.<ref name=":92"/> [[File:Nicrophorus humator - sexton beetle - Flickr - Nick Goodrum Photography.jpg|thumb|Burying beetle with ''Poecilochirus'' mites]] Dung and carrion are ephemeral habitats that are frequently visited by beetles (such as dung beetles and burying beetles). Phoretic nematodes (''Rhabditoides'') and mites (e.g. genera ''Macrocheles'', ''Poecilochirus'', ''Uroobovella'') use the beetles to reach these rich resources, where they themselves reproduce.<ref>{{Cite journal|last1=Wang|first1=Yin|last2=Rozen|first2=Daniel E.|date=2018-12-19|title=Fitness costs of phoretic nematodes in the burying beetle, ''Nicrophorus vespilloides''|journal= Ecology and Evolution |volume=9|issue=1|pages=26–35|doi=10.1002/ece3.4570|issn=2045-7758|pmc=6342123|pmid=30680093}}</ref><ref>{{Cite journal|last1=Nehring|first1=Volker|last2=Müller|first2=Josef K.|last3=Steinmetz|first3=Nadine|date=2017|title=Phoretic Poecilochirus mites specialize on their burying beetle hosts|url= |journal= Ecology and Evolution |language=en|volume=7|issue=24|pages=10743–10751|doi=10.1002/ece3.3591|issn=2045-7758|pmc=5743630|pmid=29299254}}</ref><ref>{{Cite journal|last1=Niogret|first1=Jérôme|last2=Lumaret|first2=Jean-Pierre|last3=Bertrand|first3=Michel|date=2010|editor-last=Sabelis|editor-first=Maurice W.|editor2-last=Bruin|editor2-first=Jan|title=Generalist and specialist strategies in macrochelid mites (Acari: Mesostigmata) phoretically associated with dung beetles (Coleoptera: Scarabaeidae)|url=https://link.springer.com/chapter/10.1007/978-90-481-9837-5_55|journal= Trends in Acarology |language=en|location=Dordrecht|publisher=Springer Netherlands|pages=343–347|doi=10.1007/978-90-481-9837-5_55|isbn=978-90-481-9837-5|url-access=subscription}}</ref>
The pseudoscorpion ''Cordylochernes scorpioides'' often "hitchikes" on harlequin beetles (''Acrocinus longimanus''). Initially, there were a number of alternate hypothesis for why the pseudoscorpions were found on the beetles: by accident, to forage for mites inhabiting the beetle, or as an obligate parasite. Evidence suggested, however, that the pseudoscorpions were using beetles to travel from tree to tree, where they preyed upon other beetle larvae.<ref name=":62"/>
If their host dies, lice can opportunistically use phoresis to hitch a ride on a fly, and attempt to find a new host.<ref>{{cite book|title=Ecology and Evolution of Transmission in Feather-feeding Lice (Phthiraptera: Ischnocera)|author= University of Utah |url=https://books.google.com/books?id=RUfFjqPoQTEC&pg=PA83 |year=2008 |isbn=978-0-549-46429-7 |pages=83–87}}</ref>
The largest mammalian example of phoresis is human beings directly riding on horses or other animals, or using them to pull vehicles with humans in them.{{Citation needed|date=May 2026}}
== See also == *{{section link|Animal locomotion|Animal transport}} *Hitchhiking
==References== {{Reflist}}
== External links == * {{Commons category-inline|Phoresis}}
{{Biological_interaction-footer}}
Category:Symbiosis Category:Animal locomotion