Editing Cavitation (section)

==In nature==

===Geology===
Some hypotheses{{by whom|date=December 2019}}{{example needed|date=December 2019}} relating to [[diamond]] formation posit a possible role for cavitation—namely cavitation in the [[kimberlite]] [[Volcanic pipe|pipes]] providing the extreme pressure needed to change pure [[carbon]] into the rare [[allotrope]] that is diamond. The loudest three sounds ever recorded, during the [[1883 eruption of Krakatoa]], are now{{when|date=December 2019}} understood as the bursts of three huge cavitation bubbles, each larger than the last, formed in the volcano's throat. Rising magma, filled with dissolved gasses and under immense pressure, encountered a different magma that compressed easily, allowing bubbles to grow and combine.<ref>{{Cite web |url=https://volcanoes.usgs.gov/observatories/hvo/hvo_volcano_watch.html|author=Hawaiian Volcano Observatory|date=May 25, 2017|title=Volcano Watch — Volcanoes, Landslides, and Angry Gods—A Pacific Northwest Connection|publisher=USGS|website=Volcano Watch|access-date=2017-05-28}}{{verify source|date=May 2022|reason=The original URL pointed to a dynmaic webpage that changed weekly. It know points to the article that was available 2017-05-28. It does not contain the info mentioned.}}</ref><ref>{{cite book |first1=Alexander G.|last1=Simakin|first2=Ahmad|last2=Ghassemi|editor1-first=Gemma|editor1-last=Aiello |date=2018|title=Volcanoes: Geological & Geophysical Setting, Theoretical Aspects & Numerical Modeling, Applications to Industry & Their Impact on the Human Health|page=176 |chapter=Mechanics of magma chamber with the implication of the effect of CO2 fluxing|publisher=BoD – Books on Demand |isbn=978-1-7892-3348-3 |chapter-url=https://books.google.com/books?id=BDGQDwAAQBAJ&pg=PA176 |access-date=2020-04-30}}</ref>

===Vascular plants===
Cavitation can occur in the [[xylem]] of [[vascular plants]].<ref>{{cite journal |last1=Caupin |first1=Frédéric |last2=Herbert |first2=Eric |title=Cavitation in water: a review |journal=Comptes Rendus Physique |date=2006 |volume=7 |issue=9–10 |pages=1000–1017 |doi=10.1016/j.crhy.2006.10.015|bibcode=2006CRPhy...7.1000C }}</ref><ref name="Sperry96" /> The [[sap]] vaporizes locally so that either the vessel elements or [[tracheid]]s are filled with water vapor. Plants are able to repair cavitated xylem in a number of ways. For plants less than 50&nbsp;cm tall, root pressure can be sufficient to redissolve the vapor. Larger plants direct solutes into the xylem via ''ray cells'', or in [[tracheid]]s, via osmosis through [[plant cell|bordered pits]]. Solutes attract water, the pressure rises and vapor can redissolve. In some trees, the sound of the cavitation is audible, particularly in summer, when the rate of [[evapotranspiration]] is highest. Some deciduous trees have to shed leaves in the autumn partly because cavitation increases as temperatures decrease.<ref name="Sperry96">{{cite journal |author1=Sperry, J.S. |author2=Saliendra, N.Z. |author3=Pockman, W.T. |author4=Cochard, H. |author5=Cuizat, P. |author6=Davis, S.D. |author7=Ewers, F.W. |author8=Tyree, M.T. |date=1996 |title=New evidence for large negative xylem pressures and their measurement by the pressure chamber technique |journal=Plant Cell Environ. |volume=19 |pages=427–436|doi=10.1111/j.1365-3040.1996.tb00334.x }}</ref>

===Spore dispersal in plants===
Cavitation plays a role in the spore dispersal mechanisms of certain plants. In [[fern]]s, for example, the fern sporangium acts as a catapult that launches spores into the air. The charging phase of the catapult is driven by water evaporation from the [[annulus (botany)|annulus]] cells, which triggers a pressure decrease. When the compressive pressure reaches approximately 9{{nbsp}}[[Pascal (unit)|MPa]], cavitation occurs. This rapid event triggers spore dispersal due to the [[elastic energy]] released by the annulus structure. The initial spore acceleration is extremely large – up to 10{{sup|5}} times the [[gravitational acceleration]].<ref name="NoblinRojas2012">{{cite journal |last1=Noblin|first1=X.|last2=Rojas|first2=N. O. |last3=Westbrook|first3=J.|last4=Llorens|first4=C.|last5=Argentina|first5=M.|last6=Dumais|first6=J. |title=The Fern Sporangium: A Unique Catapult|journal=Science|volume=335 |issue=6074|year=2012|pages=1322 |issn=0036-8075|doi=10.1126/science.1215985|pmid=22422975|bibcode=2012Sci...335.1322N|s2cid=20037857 |url=https://hal.archives-ouvertes.fr/hal-00826001/file/1215985_maintext-resumitted2-for-HAL.pdf |archive-url=https://web.archive.org/web/20190504014851/https://hal.archives-ouvertes.fr/hal-00826001/file/1215985_maintext-resumitted2-for-HAL.pdf |archive-date=2019-05-04 |url-status=live}}</ref>

===Marine life===
Just as cavitation bubbles form on a fast-spinning boat propeller, they may also form on the tails and fins of aquatic animals. This primarily occurs near the surface of the ocean, where the ambient water pressure is low.

Cavitation may limit the maximum swimming speed of powerful swimming animals like [[dolphins]] and [[tuna]].<ref>{{cite magazine | last = Brahic | first = Catherine | title = Dolphins swim so fast it hurts   | magazine = New Scientist | date = 2008-03-28 | url = https://www.newscientist.com/channel/life/dn13553-dolphins-swim-so-fast-it-hurts.html | access-date = 2008-03-31}}</ref> Dolphins may have to restrict their speed because collapsing cavitation bubbles on their tail are painful. Tuna have bony fins without nerve endings and do not feel pain from cavitation. They are slowed down when cavitation bubbles create a vapor film around their fins. Lesions have been found on tuna that are consistent with cavitation damage.<ref name="IosilevskiiWeihs2008">{{cite journal|last1=Iosilevskii|first1=G|last2=Weihs|first2=D|title=Speed limits on swimming of fishes and cetaceans|journal=Journal of the Royal Society Interface|volume=5|issue=20|year=2008|pages=329–338|issn=1742-5689|doi=10.1098/rsif.2007.1073|pmid=17580289|pmc=2607394}}</ref>

Some sea animals have found ways to use cavitation to their advantage when hunting prey. The [[pistol shrimp]] snaps a specialized claw to create cavitation, which can kill small fish. The [[mantis shrimp]] (of the ''smasher'' variety) uses cavitation as well in order to stun, smash open, or kill the shellfish that it feasts upon.<ref>{{cite web|last=Patek|first=Sheila|title=Sheila Patek clocks the fastest animals|url=http://www.ted.com/talks/sheila_patek_clocks_the_fastest_animals.html|publisher=TED|access-date=18 February 2011}}</ref>

[[Thresher sharks]] use 'tail slaps' to debilitate their small fish prey and cavitation bubbles have been seen rising from the apex of the tail arc.<ref name="TsiklirasOliver2013">{{cite journal|last1=Tsikliras|first1=Athanassios C.|last2=Oliver|first2=Simon P.|last3=Turner|first3=John R.|last4=Gann|first4=Klemens|last5=Silvosa|first5=Medel|last6=D'Urban Jackson|first6=Tim|title=Thresher Sharks Use Tail-Slaps as a Hunting Strategy|journal=PLOS ONE|volume=8|issue=7|year=2013|pages=e67380|issn=1932-6203|doi=10.1371/journal.pone.0067380|pmid=23874415|pmc=3707734|bibcode = 2013PLoSO...867380O |doi-access=free}}</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211205/lHoCCPsRuhg Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20130825141415/http://www.youtube.com/watch?v=lHoCCPsRuhg&gl=US&hl=en Wayback Machine]{{cbignore}}: {{cite web| url = https://www.youtube.com/watch?v=lHoCCPsRuhg| title = THRESHER SHARKS KILL PREY WITH TAIL | website=[[YouTube]]| date = July 12, 2013 }}{{cbignore}}</ref>

===Coastal erosion===
In the last half-decade,{{when|date=December 2019}} [[coastal erosion]] in the form of inertial cavitation has been generally accepted.<ref>{{cite book |title=Environmental Geomorphology |url=https://archive.org/details/environmentalgeo00pani |url-access=limited |last=Panizza |first=Mario  |year=1996 |publisher=Elsevier |location=Amsterdam; New York |isbn=978-0-444-89830-2 |pages=[https://archive.org/details/environmentalgeo00pani/page/n123 112]–115 }}</ref> Bubbles in an incoming wave are forced into cracks in the cliff being eroded. Varying pressure decompresses some vapor pockets which subsequently implode. The resulting pressure peaks can blast apart fractions of the rock.