Editing Venom (section)

==Taxonomic range==
Venom is widely distributed taxonomically, being found in both invertebrates and vertebrates, in aquatic and terrestrial animals, and among both predators and prey. The major groups of venomous animals are described below.

===Arthropods===
Venomous arthropods include [[spider]]s, which use fangs on their [[chelicerae]] to [[spider bite|inject venom]], and [[centipede]]s, which use {{nowrap|[[forcipule]]s{{tsp}}{{mdash}}{{tsp}}}}modified {{nowrap|legs{{tsp}}{{mdash}}{{tsp}}}}to deliver venom, while [[scorpion]]s and stinging [[insect]]s inject venom with a sting. In [[bee]]s and [[wasp]]s, the stinger is a modified [[ovipositor]] (egg-laying device). In ''[[Polistes fuscatus]]'', the female continuously releases a venom that contains a sex pheromone that induces copulatory behavior in males.<ref>{{cite journal |last=Post Downing |first=Jeanne |year=1983 |title=Venom: Source of a Sex Pheromone in the Social Wasp Polistes fuscatus (Hymenoptera: Vespidae) |journal=Journal of Chemical Ecology |volume=9 |issue=2 |pages=259–266 |doi=10.1007/bf00988043 |pmid=24407344 |bibcode=1983JCEco...9..259P |s2cid=32612635 }}</ref> In <!--many -->wasps such as ''[[Polistes exclamans]]'', venom is used as an alarm pheromone, coordinating a response from the nest and attracting nearby wasps to attack the predator.<ref>{{cite journal |last=Post Downing |first=Jeanne  |year=1984 |title=Alarm response to venom by social wasps Polistes exclamans and P. fuscatus |journal=Journal of Chemical Ecology |volume=10 |issue=10 |pages=1425–1433 |doi=10.1007/BF00990313 |pmid=24318343 |s2cid=38398672 }}</ref> In some species, such as ''[[Parischnogaster striatula]]'',  venom is applied all over the body as an antimicrobial protection.<ref>{{Cite journal |title=From individual to collective immunity: The role of the venom as antimicrobial agent in the Stenogastrinae wasp societies |last=Baracchi |first=David |date=January 2012 |journal=Journal of Insect Physiology |doi=10.1016/j.jinsphys.2011.11.007 |pmid=22108024 |volume=58 |issue=1 |pages=188–193 |bibcode=2012JInsP..58..188B |hdl=2158/790328 |s2cid=206185438 |hdl-access=free }}</ref>

Many [[caterpillar]]s have defensive venom glands associated with specialized bristles on the body called [[urtication|urticating hairs]]. These are usually merely irritating, but those of the ''[[Lonomia]]'' moth can be fatal to humans.<ref name="PintoBergerReckTerra 2010">{{cite journal |last1=Pinto |first1=Antônio F. M. |last2=Berger |first2=Markus |last3=Reck |first3=José |last4=Terra |first4=Renata M. S. |last5=Guimarães |first5=Jorge A. |title=Lonomia obliqua venom: In vivo effects and molecular aspects associated with the hemorrhagic syndrome |journal=Toxicon |volume=56 |issue=7 |date=15 December 2010 |pmid=20114060 |doi=10.1016/j.toxicon.2010.01.013 |pages=1103–1112|bibcode=2010Txcn...56.1103P }}</ref>

Bees synthesize and employ an acidic venom ([[apitoxin]]) to defend their hives and food stores, whereas wasps use a chemically different venom to paralyse prey, so their prey remains alive to provision the food chambers of their young. The use of venom is much more widespread than just these examples; many other insects, such as [[Hemiptera|true bug]]s and many [[ant]]s, also produce venom.<ref>{{Cite journal |last1=Touchard |first1=Axel |last2=Aili |first2=Samira |last3=Fox |first3=Eduardo |last4=Escoubas |first4=Pierre |last5=Orivel |first5=Jérôme |last6=Nicholson |first6=Graham |last7=Dejean |first7=Alain |display-authors=3 |date=20 January 2016 |title=The Biochemical Toxin Arsenal from Ant Venoms |journal=Toxins |volume=8 |issue=1 |page=30 |doi=10.3390/toxins8010030 |pmid=26805882 |pmc=4728552 |issn=2072-6651 |doi-access=free}}</ref> The ant species ''[[Polyrhachis dives]]'' uses venom [[topically]] for the sterilisation of pathogens.<ref>{{cite journal |last1=Graystock |first1=Peter |last2=Hughes |first2=William O. H. |title=Disease resistance in a weaver ant, Polyrhachis dives, and the role of antibiotic-producing glands |journal=Behavioral Ecology and Sociobiology |year=2011 |doi=10.1007/s00265-011-1242-y |volume=65 |issue=12 |pages=2319–2327|bibcode=2011BEcoS..65.2319G |s2cid=23234351 }}</ref>

===Other invertebrates===
[[File:Irukandji-jellyfish-queensland-australia.jpg|thumb|The fingernail-sized box jellyfish ''[[Malo kingi]]'' has among the most dangerous venom of any animal, causing [[Irukandji syndrome]]⁠{{nowrap|{{hsp}}{{mdash}}{{hsp}}}}severe pain, vomiting, and rapid rise in blood pressure]]

There are venomous invertebrates in several [[phylum|phyla]], including [[jellyfish]] such as the dangerous [[box jellyfish]],<ref>{{cite magazine |last1=Frost |first1=Emily |title=What's Behind That Jellyfish Sting? |url=https://www.smithsonianmag.com/science-nature/whats-behind-that-jellyfish-sting-2844876/ |magazine=Smithsonian |access-date=30 September 2018 |date=30 August 2013}}</ref> the [[Portuguese man-of-war]] (a siphonophore) and [[sea anemone]]s among the [[Cnidaria]],<ref name=Bonamonte>{{cite book |last1=Bonamonte |first1=Domenico |last2=Angelini |first2=Gianni |title=Aquatic Dermatology: Biotic, Chemical and Physical Agents |url=https://books.google.com/books?id=A4cSDQAAQBAJ&pg=PA54 |year=2016 |publisher=Springer International |isbn=978-3-319-40615-2 |pages=54–56}}</ref> [[sea urchin]]s among the [[Echinodermata]],<ref>{{Cite journal |last=Gallagher |first=Scott A. |title=Echinoderm Envenomation |url=http://emedicine.medscape.com/article/770053-overview |journal=EMedicine |access-date=12 October 2010 |date=2017-08-02 }}</ref> and [[cone snails]]<ref name="OliveraTeichert2007">{{cite journal |last1=Olivera |first1=B. M. |last2=Teichert |first2=R. W. |title=Diversity of the neurotoxic Conus peptides: a model for concerted pharmacological discovery |journal=Molecular Interventions |year= 2007 |volume= 7 |issue= 5 |pages=251–260 |pmid=17932414 |doi=10.1124/mi.7.5.7}}</ref> and [[cephalopod]]s, including [[octopus]]es, among the [[Mollusc]]s.<ref>{{cite magazine |last1=Barry |first1=Carolyn |title=All Octopuses Are Venomous, Study Says |url=https://www.nationalgeographic.com/animals/2009/04/octopus-venom-hunting-cephalopod/ |archive-url=https://web.archive.org/web/20180930193124/https://www.nationalgeographic.com/animals/2009/04/octopus-venom-hunting-cephalopod/ |url-status=dead |archive-date=30 September 2018 |magazine=[[National Geographic]] |access-date=30 September 2018 |date=17 April 2009}}</ref>

===Vertebrates===
====Fish====
{{Main|Venomous fish}}

Venom is found in some 200 cartilaginous fishes, including [[stingrays]], [[shark]]s, and [[chimaera]]s; the [[Siluriformes|catfishes]] (about 1000 venomous species); and 11 [[clade]]s of spiny-rayed fishes ([[Acanthomorpha]]), containing the [[Scorpaenidae|scorpionfishes]] (over 300 species), [[stonefish]]es (over 80 species), [[Neosebastidae|gurnard perches]], [[blenny|blennies]], [[rabbitfishes]], [[surgeonfish]]es, some [[Aploactinidae|velvetfishes]], some [[toadfish]]es, [[coral croucher]]s, [[Gnathanacanthidae|red velvetfishes]], [[Scatophagidae|scats]], [[Sebastidae|rockfishes]], [[Setarchidae|deepwater scorpionfishes]], [[waspfish]]es, [[Trachinidae|weevers]], and [[Uranoscopidae|stargazers]].<!-- All these are cited to SmithWheeler2006, please do not add to list without citing separately to avoid confusion. --><ref name="SmithWheeler2006">{{cite journal |last1=Smith |first1=William Leo |last2=Wheeler |first2=Ward C. |title=Venom Evolution Widespread in Fishes: A Phylogenetic Road Map for the Bioprospecting of Piscine Venoms |journal=Journal of Heredity |volume=97 |issue=3 |date=2006 |doi=10.1093/jhered/esj034 |pmid=16740627 |pages=206–217 |doi-access=free }}</ref>

====Amphibians====
Some [[Salamandridae|salamanders]] can extrude sharp venom-tipped ribs.<ref>[http://www.askabiologist.org.uk/punbb/viewtopic.php?id=1494 Venomous Amphibians (Page 1) – Reptiles (Including Dinosaurs) and Amphibians – Ask a Biologist Q&A]. Askabiologist.org.uk. Retrieved on 2013-07-17.</ref><ref>{{Cite journal |last1=Nowak |first1=R. T. |last2=Brodie |first2=E. D. |title=Rib Penetration and Associated Antipredator Adaptations in the Salamander Pleurodeles waltl (Salamandridae) |journal=Copeia |volume=1978 |issue=3 |pages=424–429 |year=1978 |doi=10.2307/1443606 |jstor=1443606 }}</ref> Two frog species in Brazil have tiny spines around the crown of their skulls which, on impact, deliver venom into their targets.<ref>{{Cite journal |date=2015-08-17 |title=Venomous Frogs Use Heads as Weapons |journal=Current Biology |volume=25 |issue=16 |pages=2166–2170 |doi=10.1016/j.cub.2015.06.061 |issn=0960-9822 |last1=Jared |first1=Carlos |last2=Mailho-Fontana |first2=Pedro Luiz |last3=Antoniazzi|first3=Marta Maria |last4=Mendes |first4=Vanessa Aparecida |last5=Barbaro |first5=Katia Cristina |last6=Rodrigues |first6=Miguel Trefau t|last7=Brodie |first7=Edmund D. |display-authors=3 |pmid=26255851 |s2cid=13606620|doi-access=free |bibcode=2015CBio...25.2166J }}</ref>

====Reptiles==== 
{{Further|Big Four (Indian snakes)}}
{{Main|Snake venom|Evolution of snake venom}}
{{Multiple image
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|footer=The venom of the prairie rattlesnake, ''[[Crotalus viridis]]'' (left), includes [[metalloproteinase]]s (example on the right) which help digest prey before eating. 
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Some 450 species of snake are venomous.<ref name="SmithWheeler2006"/> [[Snake venom]] is produced by glands below the eye (the [[Submandibular gland|mandibular glands]]) and delivered to the target through tubular or channeled fangs. Snake venoms contain a variety of [[peptide]] toxins, including [[proteases]], which [[hydrolysis|hydrolyze]] protein peptide bonds; [[nucleases]], which hydrolyze the [[phosphodiester]] bonds of [[DNA]]; and neurotoxins, which disrupt signalling in the nervous system.<ref name=Bauchot>{{cite book |last=Bauchot |first=Roland |title=Snakes: A Natural History |year=1994 |publisher=Sterling |isbn=978-1-4027-3181-5 |pages=194–209}}</ref> Snake venom causes symptoms including pain, swelling, tissue necrosis, low blood pressure, convulsions, haemorrhage (varying by species of snake), respiratory paralysis, kidney failure, coma, and death.<ref>{{cite web |title=Snake Bites |url=http://eclinicalworks.adam.com/content.aspx?productId=39&pid=1&gid=000031&print=1 |publisher=A. D. A. M. Inc |access-date=30 September 2018 |date=16 October 2017}}</ref> Snake venom may have originated with [[gene duplication|duplication of genes]] that had been expressed in the [[salivary gland]]s of ancestors.<ref name="HargreavesSwainHegartyLogan2014">{{cite journal |last1=Hargreaves |first1=Adam D. |last2=Swain |first2=Martin T. |last3=Hegarty |first3=Matthew J. |last4=Logan |first4=Darren W. |last5=Mulley |first5=John F. |title=Restriction and Recruitment—Gene Duplication and the Origin and Evolution of Snake Venom Toxins |journal=Genome Biology and Evolution |volume=6 |issue=8 |date=30 July 2014 |doi=10.1093/gbe/evu166 |pmid=25079342 |pmc=4231632 |pages=2088–2095}}</ref><ref>{{cite journal |last1=Daltry |first1=Jennifer C. |author2=Wuester, Wolfgang |author3=Thorpe, Roger S. |year=1996 |title=Diet and snake venom evolution |journal=Nature |volume=379 |issue=6565 |pages=537–540 |doi=10.1038/379537a0 |pmid=8596631|bibcode=1996Natur.379..537D |s2cid=4286612 }}</ref>

Venom is found in a few other reptiles such as the [[Mexican beaded lizard]],<ref name="Cantrell2003">{{cite journal |last=Cantrell |first=F. L. |title=Envenomation by the Mexican beaded lizard: a case report |journal=Journal of Toxicology. Clinical Toxicology |volume=41 |issue=3 |year=2003 |pmid=12807305 |pages=241–244 |doi=10.1081/CLT-120021105 |s2cid=24722441 }}</ref> the [[gila monster]],<ref name=Mullin2015/> and some monitor lizards, including the [[Komodo dragon]].<ref name=fries>{{cite journal |last1=Fry |first1=B. G. |author2=Wroe, S. |author3=Teeuwisse, W. |title=A central role for venom in predation by ''Varanus komodoensis'' (Komodo Dragon) and the extinct giant ''Varanus'' (''Megalania'') ''priscus'' |journal=PNAS |volume=106 |issue=22 |pages=8969–8974 |date=June 2009 |pmid=19451641 |pmc=2690028 |doi=10.1073/pnas.0810883106 |bibcode=2009PNAS..106.8969F |doi-access=free }}</ref> Mass spectrometry showed that the mixture of proteins present in their venom is as complex as the mixture of proteins found in snake venom.<ref name=fries/><ref>Fry, B. G.; Wuster, W.; Ramjan, S. F. R.; Jackson, T.; Martelli, P.; Kini, R. M. 2003c. Analysis of [[Colubroidea]] snake venoms by liquid chromatography with mass spectrometry: Evolutionary and toxinological implications. Rapid Communications in Mass Spectrometry 17:2047-2062.</ref>
Some lizards possess a venom gland; they form a hypothetical clade, [[Toxicofera]], containing the suborders [[Serpentes]] and [[Iguania]] and the families [[Varanidae]], [[Anguidae]], and [[Helodermatidae]].<ref name="Fry2006">{{cite journal |date=February 2006 |title=Early evolution of the venom system in lizards and snakes |journal=Nature |volume=439 |pages=584–588 |doi=10.1038/nature04328 |pmid=16292255 |last1=Fry |first1=B. G. |author2=Vidal, N. |author3=Norman, J. A. |author4=Vonk, F. J. |author5=Scheib, H. |author6=Ramjan, S. F. |author7=Kuruppu, S. |author8=Fung, K. |author9=Hedges, S. B. |author10=Richardson, M. K. |author11=Hodgson, W. C. |author12=Ignjatovic, V. |author13=Summerhayes, R. |author14=Kochva, E. |display-authors=3 |issue=7076 |bibcode=2006Natur.439..584F |s2cid=4386245 }}</ref>

====Mammals====
{{Main|Venomous mammal}}

''[[Euchambersia]]'', an extinct genus of [[therocephalia]]ns, is hypothesized to have had venom glands attached to its canine teeth.<ref name="2017ct">{{cite journal |last1=Benoit |first1=J. |last2=Norton |first2=L. A. |last3=Manger |first3=P. R. |last4=Rubidge |first4=B. S. |title=Reappraisal of the envenoming capacity of ''Euchambersia mirabilis'' (Therapsida, Therocephalia) using μCT-scanning techniques |date=2017 |journal=PLOS ONE |volume=12 |issue=2 |page=e0172047 |doi=10.1371/journal.pone.0172047 |pmid=28187210 |pmc=5302418 |bibcode=2017PLoSO..1272047B |doi-access=free }}</ref>

A few species of living mammals are venomous, including [[solenodon]]s, [[shrews]], the [[European mole]], [[vampire bat]]s, male [[platypus]]es, and [[slow loris]]es.<ref name="SmithWheeler2006"/><ref>{{Cite journal |last1=Nekaris |first1=K. Anne-Isola |last2=Moore |first2=Richard S. |last3=Rode |first3=E. Johanna |last4=Fry |first4=Bryan G. |date=2013-09-27 |title=Mad, bad and dangerous to know: the biochemistry, ecology and evolution of slow loris venom |journal=Journal of Venomous Animals and Toxins Including Tropical Diseases |volume=19 |issue=1 |page=21 |doi=10.1186/1678-9199-19-21|pmid=24074353 |pmc=3852360 |doi-access=free }}</ref> Shrews have venomous saliva and most likely evolved their trait similarly to snakes.<ref>{{cite journal |last1=Ligabue-Braun |first1=R. |author2=Verli, H. |author3=Carlini, C. R. |year=2012 |title=Venomous mammals: a review |journal=Toxicon |volume=59 |issue=7–8 |pages=680–695 |doi=10.1016/j.toxicon.2012.02.012|pmid=22410495 |bibcode=2012Txcn...59..680L }}</ref> The presence of tarsal spurs akin to those of the platypus in many non-[[theria]]n [[Mammaliaformes]] groups suggests that venom was an ancestral characteristic among mammals.<ref>Jørn H. Hurum, Zhe-Xi Luo, and Zofia Kielan-Jaworowska, Were mammals originally venomous?, Acta Palaeontologica Polonica 51 (1), 2006: 1-11</ref>

Extensive research on platypuses shows that their toxin was initially formed from gene duplication, but data provides evidence that the further evolution of platypus venom does not rely as much on gene duplication as was once thought.<ref>{{cite journal |last1=Wong |first1=E. S. |last2=Belov |first2=K. |year=2012 |title=Venom evolution through gene duplications |journal=Gene |volume=496 |issue=1 |pages=1–7 |doi= 10.1016/j.gene.2012.01.009 |pmid=22285376 }}</ref> Modified sweat glands are what evolved into platypus venom glands. Although it is proven that reptile and platypus venom have independently evolved, it is thought that there are certain protein structures that are favored to evolve into toxic molecules. This provides more evidence of why venom has become a homoplastic trait and why very different animals have convergently evolved.<ref name="whittington" />