Editing Mammal (section)

==Humans and other mammals==
{{Main|Human uses of mammals}}

===In human culture===
[[File:Lascaux painting.jpg|thumb|[[Upper Paleolithic]] [[cave painting]] of a variety of large mammals, [[Lascaux]], {{circa|17,300}} years old]]

Non-human mammals play a wide variety of roles in human culture. They are the most popular of [[pet]]s, with tens of millions of dogs, cats and other animals including [[rabbit]]s and mice kept by families around the world.<ref>{{cite journal | vauthors = Murthy R, Bearman G, Brown S, Bryant K, Chinn R, Hewlett A, George BG, Goldstein EJ, Holzmann-Pazgal G, Rupp ME, Wiemken T, Weese JS, Weber DJ | display-authors = 6 | title = Animals in healthcare facilities: recommendations to minimize potential risks | journal = Infection Control and Hospital Epidemiology | volume = 36 | issue = 5 | pages = 495–516 | date = May 2015 | pmid = 25998315 | doi = 10.1017/ice.2015.15 |doi-access=free | s2cid = 541760 | url = https://www.cambridge.org/core/services/aop-cambridge-core/content/view/7086725BAB2AAA4C1949DA5B90F06F3B/S0899823X1500015Xa.pdf/div-class-title-animals-in-healthcare-facilities-recommendations-to-minimize-potential-risks-div.pdf |url-status=live |archive-url=https://web.archive.org/web/20231103092334/https://www.cambridge.org/core/services/aop-cambridge-core/content/view/7086725BAB2AAA4C1949DA5B90F06F3B/S0899823X1500015Xa.pdf/div-class-title-animals-in-healthcare-facilities-recommendations-to-minimize-potential-risks-div.pdf |archive-date=3 November 2023 }}</ref><ref>{{cite web |last=The Humane Society of the United States |title=U.S. Pet Ownership Statistics |url=https://www.humanesociety.org/issues/pet_overpopulation/facts/pet_ownership_statistics.html |access-date=27 April 2012 |archive-date=7 April 2012 |archive-url=https://web.archive.org/web/20120407193941/http://www.humanesociety.org/issues/pet_overpopulation/facts/pet_ownership_statistics.html |url-status=dead }}</ref><ref>{{cite web |last=USDA |title=U.S. Rabbit Industry profile |url=https://www.aphis.usda.gov/animal_health/emergingissues/downloads/RabbitReport1.pdf |access-date=10 July 2013 |archive-url=https://web.archive.org/web/20190807115557/http://www.aphis.usda.gov/animal_health/emergingissues/downloads/RabbitReport1.pdf |archive-date=7 August 2019 |url-status=dead }}</ref> Mammals such as [[mammoth]]s, horses and deer are among the earliest subjects of art, being found in [[Upper Paleolithic]] [[cave painting]]s such as at [[Lascaux]].<ref>{{Cite news |vauthors=McKie R |title=Prehistoric cave art in the Dordogne |url=https://www.theguardian.com/travel/2013/may/26/prehistoric-cave-art-dordogne |newspaper=[[The Guardian]] |access-date=9 November 2016 |date=26 May 2013 |archive-date=31 May 2021 |archive-url=https://web.archive.org/web/20210531050457/https://www.theguardian.com/travel/2013/may/26/prehistoric-cave-art-dordogne |url-status=live }}</ref> Major artists such as [[Albrecht Dürer]]<!--rhino-->, [[George Stubbs]]<!--horses--> and [[Edwin Landseer]]<!--red deer--> are known for their portraits of mammals.<ref name="Jones">{{cite news |vauthors=Jones J |title=The top 10 animal portraits in art |url=https://www.theguardian.com/artanddesign/jonathanjonesblog/2014/jun/27/top-10-animal-portraits-in-art |access-date=24 June 2016 |agency=[[The Guardian]] |date=27 June 2014 |archive-date=18 May 2016 |archive-url=https://web.archive.org/web/20160518105922/http://www.theguardian.com/artanddesign/jonathanjonesblog/2014/jun/27/top-10-animal-portraits-in-art |url-status=live }}</ref> Many species of mammals have been [[hunting|hunted]] for sport and for food; deer and [[wild boar]] are especially popular as [[game (hunting)|game animals]].<ref>{{cite web | title=Deer Hunting in the United States: An Analysis of Hunter Demographics and Behavior Addendum to the 2001 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation Report 2001-6 | url=https://digitalmedia.fws.gov/cdm/ref/collection/document/id/292 | publisher=Fishery and Wildlife Service (US) | access-date=24 June 2016 | archive-date=13 August 2016 | archive-url=https://web.archive.org/web/20160813200949/http://digitalmedia.fws.gov/cdm/ref/collection/document/id/292 | url-status=live }}</ref><ref>{{cite web | vauthors = Shelton L | work = The Natchez Democrat | title=Recreational Hog Hunting Popularity Soaring | url=https://www.grandviewoutdoors.com/big-game-hunting/recreational-hog-hunting-popularity-soaring/ | publisher=Grand View Outdoors | access-date=24 June 2016 | date=5 April 2014 | archive-url=https://web.archive.org/web/20171212193350/https://www.grandviewoutdoors.com/big-game-hunting/recreational-hog-hunting-popularity-soaring/ | archive-date=12 December 2017 | url-status=dead }}</ref><ref>{{cite book | vauthors = Nguyen J, Wheatley R | title=Hunting For Food: Guide to Harvesting, Field Dressing and Cooking Wild Game | url={{Google books|plainurl=yes|id=3XN6CgAAQBAJ|page=6}} | year=2015 | publisher=F+W Media | isbn=978-1-4403-3856-4 | pages=6–77}} Chapters on hunting deer, wild hog (boar), rabbit, and squirrel.</ref> Mammals such as [[horse racing|horses]] and [[greyhound racing|dogs]] are widely raced for sport, often combined with [[gambling|betting on the outcome]].<ref>{{cite encyclopedia |title=Horse racing | encyclopedia = The Encyclopædia Britannica |url= https://www.britannica.com/EBchecked/topic/272329/horse-racing |access-date=6 May 2014 |archive-url=https://web.archive.org/web/20131221033444/https://www.britannica.com/EBchecked/topic/272329/horse-racing |archive-date= 21 December 2013}}</ref><ref>{{cite book | vauthors = Genders R |title=Encyclopaedia of Greyhound Racing |year=1981 |publisher=Pelham Books |isbn=978-0-7207-1106-6|oclc=9324926}}</ref> There is a tension between the role of animals as companions to humans, and their existence as individuals with [[animal rights|rights of their own]].<ref>{{cite journal |title=The Role of Animals in Human Society | vauthors = Plous S |date=1993 |doi=10.1111/j.1540-4560.1993.tb00906.x |journal=Journal of Social Issues |volume=49 |issue=1 |pages=1–9}}</ref> Mammals further play a wide variety of roles in literature,<ref>{{Cite news|vauthors=Fowler KJ|title=Top 10 books about intelligent animals<!--all 10 are mammals...-->|url=https://www.theguardian.com/books/2014/mar/26/top-10-books-intelligent-animals-watership-down-animal-farm|newspaper=The Guardian|access-date=9 November 2016|date=26 March 2014|archive-date=28 May 2021|archive-url=https://web.archive.org/web/20210528154902/https://www.theguardian.com/books/2014/mar/26/top-10-books-intelligent-animals-watership-down-animal-farm|url-status=live}}</ref><ref>{{cite book | vauthors = Gamble N, Yates S |title=Exploring Children's Literature |year=2008 |publisher=Sage |isbn=978-1-4129-3013-0 |edition=2nd |location=Los Angeles |oclc=71285210}}</ref><ref>{{cite web|title=Books for Adults|url=https://www.sealsitters.org/marine_mammals/reading.html|website=Seal Sitters|access-date=9 November 2016|archive-date=11 July 2016|archive-url=https://web.archive.org/web/20160711034305/http://www.sealsitters.org/marine_mammals/reading.html|url-status=live}}</ref> film,<ref>{{cite journal | vauthors = Paterson J |title=Animals in Film and Media |journal=Oxford Bibliographies |year=2013 |doi=10.1093/obo/9780199791286-0044}}</ref> mythology, and religion.<ref>{{cite book | vauthors = Johns C |date=2011 |title=Cattle: History, Myth, Art |publisher=The British Museum Press |isbn=978-0-7141-5084-0 |location=London |oclc=665137673}}</ref><ref>{{cite book |title=Hayagrīva: The Mantrayānic Aspect of Horse-cult in China and Japan |publisher=Brill Archive |page=9 | vauthors = van Gulik RH }}</ref><ref>{{cite web| vauthors = Grainger R |title=Lion Depiction across Ancient and Modern Religions |url=https://lionalert.org/page/Lion_Depiction_Across_Ancient_and_Modern_Religions |publisher=ALERT |access-date=6 November 2016 |date=24 June 2012 |url-status=dead |archive-url=https://web.archive.org/web/20160923134807/https://lionalert.org/page/Lion_Depiction_Across_Ancient_and_Modern_Religions |archive-date=23 September 2016 }}</ref>

===Uses and importance===
{{See also|Livestock|Laboratory animal|Pack animal}}
[[File:Hand milking a cow at Cobbes Farm Museum.jpg|thumb|left|upright|[[Cattle]] have been [[dairy farming|kept for milk]] for thousands of years.]]

The domestication of mammals was instrumental in the [[Neolithic Revolution|Neolithic development of agriculture]] and of [[civilisation]], causing farmers to replace [[hunter-gatherer]]s around the world.{{efn|Diamond discussed this matter further in his 1997 book ''[[Guns, Germs, and Steel]]''.<ref>{{cite book | vauthors = Diamond JM |author-link=Jared Diamond |year=1997 |title=Guns, Germs, and Steel: the Fates of Human Societies|chapter=Part 2: The rise and spread of food production |location=New York |publisher=W.W. Norton & Company|isbn=978-0-393-03891-0 |oclc=35792200 |chapter-url={{Google books|plainurl=yes |id=PWnWRFEGoeUC |page=176 }}}}</ref>}}<ref name="Larson">{{cite journal | vauthors = Larson G, Burger J | title = A population genetics view of animal domestication | journal = Trends in Genetics | volume = 29 | issue = 4 | pages = 197–205 | date = April 2013 | pmid = 23415592 | doi = 10.1016/j.tig.2013.01.003 | url = https://www.palaeobarn.com/sites/domestication.org.uk/files/downloads/98.pdf | access-date = 9 November 2016 | archive-date = 8 June 2019 | archive-url = https://web.archive.org/web/20190608065300/http://www.palaeobarn.com/sites/domestication.org.uk/files/downloads/98.pdf | url-status = dead }}</ref> This transition from hunting and gathering to [[pastoralism|herding flocks]] and [[agriculture|growing crops]] was a major step in human history. The new agricultural economies, based on domesticated mammals, caused "radical restructuring of human societies, worldwide alterations in biodiversity, and significant changes in the Earth's landforms and its atmosphere... momentous outcomes".<ref>{{cite journal | vauthors = Zeder MA | title = Domestication and early agriculture in the Mediterranean Basin: Origins, diffusion, and impact | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 105 | issue = 33 | pages = 11597–11604 | date = August 2008 | pmid = 18697943 | pmc = 2575338 | doi = 10.1073/pnas.0801317105 | bibcode = 2008PNAS..10511597Z | doi-access = free }}</ref>

[[Domestication|Domestic]] mammals form a large part of the [[livestock]] raised for [[meat]] across the world. They include (2009) around 1.4&nbsp;billion [[cattle]], 1&nbsp;billion [[sheep]], 1&nbsp;billion [[domestic pig]]s,<ref>{{Cite news |title=Graphic detail Charts, maps and infographics. Counting chickens |newspaper=The Economist |url=https://www.economist.com/blogs/dailychart/2011/07/global-livestock-counts |access-date=6 November 2016 |date=27 July 2011 |archive-date=15 July 2016 |archive-url=https://web.archive.org/web/20160715181213/http://www.economist.com/blogs/dailychart/2011/07/global-livestock-counts |url-status=live }}</ref><ref>{{cite web |work=Cattle Today |url=https://cattle-today.com/ |title=Breeds of Cattle at CATTLE TODAY |publisher=Cattle-today.com |access-date=6 November 2016 |archive-date=15 July 2011 |archive-url=https://web.archive.org/web/20110715234745/https://cattle-today.com/ |url-status=live }}</ref> and (1985) over 700&nbsp;million rabbits.<ref>{{cite web |vauthors=Lukefahr SD, Cheeke PR |title=Rabbit project development strategies in subsistence farming systems |url=https://www.fao.org/docrep/U4900T/u4900T0m.htm |publisher=[[Food and Agriculture Organization]] |access-date=6 November 2016 |archive-date=6 May 2016 |archive-url=https://web.archive.org/web/20160506105314/https://www.fao.org/docrep/U4900T/u4900T0m.htm |url-status=live }}</ref> [[Working animal|Working domestic animals]] including cattle and horses have been used for work and [[transport]] from the origins of agriculture, their numbers declining with the arrival of mechanised transport and [[agricultural machinery]]. In 2004 they still provided some 80% of the power for the mainly small farms in the third world, and some 20% of the world's transport, again mainly in rural areas. In mountainous regions unsuitable for wheeled vehicles, [[pack animal]]s continue to transport goods.<ref name="Pond2004">{{cite book |vauthors=Pond WG |title=Encyclopedia of Animal Science |url=https://books.google.com/books?id=1SQl7Ao3mHoC&pg=PA248 |year=2004 |publisher=CRC Press |oclc=57033325 |isbn=978-0-8247-5496-9 |pages=248–250 |access-date=5 October 2018 |archive-date=23 January 2023 |archive-url=https://web.archive.org/web/20230123110032/https://books.google.com/books?id=1SQl7Ao3mHoC&pg=PA248 |url-status=live }}</ref> Mammal skins provide [[leather]] for [[shoe]]s, [[clothing]] and [[upholstery]]. [[Wool]] from mammals including sheep, goats and [[alpaca]]s has been used for centuries for clothing.<ref>{{cite book | vauthors = Braaten AW |title=Encyclopedia of Clothing and Fashion |year=2005 |volume=3 |publisher=[[Thomson Gale]] |isbn=978-0-684-31394-8 |oclc=963977000 |pages=[https://archive.org/details/encyclopediaofcl00vale/page/441 441–443] | veditors = Steele V |chapter=Wool |chapter-url=https://archive.org/details/encyclopediaofcl00vale/page/441 }}</ref><ref>{{cite journal | vauthors = Quiggle C | title = Alpaca: An Ancient Luxury | journal = Interweave Knits | date =Fall 2000 | pages = 74–76 }}</ref>
[[File:Distribution of Mammals on Earth.png|thumb|504x504px|Livestock make up 62% of the world's mammal biomass; humans account for 34%; and wild mammals are just 4%<ref>{{Cite web |title=Wild mammals make up only a few percent of the world's mammals |url=https://ourworldindata.org/wild-mammals-birds-biomass |date=2022-12-15 |access-date=8 August 2023 |website=[[Our World in Data]] |first=Hannah |last=Ritchie |author-link=Hannah Ritchie}}</ref>]]
Mammals serve a major role in science as [[animal model|experimental animals]], both in fundamental biological research, such as in genetics,<ref>{{cite web |title=Genetics Research |url=https://www.aht.org.uk/cms-display/genetics.html |publisher=Animal Health Trust |access-date=6 November 2016 |archive-url=https://web.archive.org/web/20171212193051/http://www.aht.org.uk/cms-display/genetics.html |archive-date=12 December 2017 |url-status=dead }}</ref> and in the development of new medicines, which must be tested exhaustively to demonstrate their [[pharmacovigilance|safety]].<ref>{{cite web |title=Drug Development |url=https://www.animalresearch.info/en/drug-development/ |publisher=Animal Research.info |access-date=6 November 2016 |archive-date=8 June 2016 |archive-url=https://web.archive.org/web/20160608124406/https://www.animalresearch.info/en/drug-development/ |url-status=live }}</ref> Millions of mammals, especially mice and rats, are used in [[animal testing|experiments]] each year.<ref name="EUstatistics2013">{{cite web |title=EU statistics show decline in animal research numbers |url=https://speakingofresearch.com/2013/12/12/eu-statistics-show-decline-in-animal-research-numbers/ |publisher=Speaking of Research |year=2013 |access-date=6 November 2016 |archive-date=24 April 2019 |archive-url=https://web.archive.org/web/20190424155141/https://speakingofresearch.com/2013/12/12/eu-statistics-show-decline-in-animal-research-numbers/ |url-status=live }}</ref> A [[knockout mouse]] is a [[genetically modified mouse]] with an inactivated [[gene]], replaced or disrupted with an artificial piece of DNA. They enable the study of [[sequencing|sequenced]] genes whose functions are unknown.<ref>{{cite journal |vauthors=Pilcher HR |url=https://www.nature.com/news/1998/030512/full/news030512-17.html |title=It's a knockout |journal=Nature |date=2003 |access-date=6 November 2016 |doi=10.1038/news030512-17 |archive-date=10 November 2016 |archive-url=https://web.archive.org/web/20161110084106/http://www.nature.com/news/1998/030512/full/news030512-17.html |url-status=live }}</ref> A small percentage of the mammals are non-human primates, used in research for their similarity to humans.<ref>{{Cite web | url=https://www.ebra.org/ebrabulletin-the-supply-and-use-of-primates-in-the-eu_17.htm | title=The supply and use of primates in the EU | year=1996 | publisher=European Biomedical Research Association | archive-url=https://web.archive.org/web/20120117061036/http://www.ebra.org/ebrabulletin-the-supply-and-use-of-primates-in-the-eu_17.htm | archive-date=17 January 2012}}</ref><ref name="Carlsson2004">{{cite journal | vauthors = Carlsson HE, Schapiro SJ, Farah I, Hau J | title = Use of primates in research: a global overview | journal = American Journal of Primatology | volume = 63 | issue = 4 | pages = 225–237 | date = August 2004 | pmid = 15300710 | doi = 10.1002/ajp.20054 | s2cid = 41368228 }}</ref><ref name="Weatherall_etal2006">{{Cite report| vauthors = Weatherall D |display-authors=etal |year=2006 |title=The use of non-human primates in research |location=London |publisher=Academy of Medical Sciences |url=https://www.acmedsci.ac.uk/images/project/nhpdownl.pdf |url-status=dead |archive-url=https://web.archive.org/web/20130323084639/http://www.acmedsci.ac.uk/images/project/nhpdownl.pdf |archive-date=23 March 2013 }}</ref>

Despite the benefits domesticated mammals had for human development, humans have an increasingly detrimental effect on wild mammals across the world. It has been estimated that the mass of all ''wild'' mammals has declined to only 4% of all mammals, with 96% of mammals being humans and their livestock now (see figure). In fact, terrestrial wild mammals make up only 2% of all mammals.<ref>{{Cite journal |vauthors=[[Hannah Ritchie|Ritchie H]], [[Max Roser|Roser M]] |date=15 April 2021 |title=Biodiversity |url=https://ourworldindata.org/mammals |journal=Our World in Data |access-date=29 August 2021 |archive-date=11 December 2022 |archive-url=https://web.archive.org/web/20221211132929/https://ourworldindata.org/mammals |url-status=live }}</ref><ref name="Bar-On_2018">{{cite journal | vauthors = Bar-On YM, Phillips R, Milo R | title = The biomass distribution on Earth | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 115 | issue = 25 | pages = 6506–6511 | date = June 2018 | pmid = 29784790 | pmc = 6016768 | doi = 10.1073/pnas.1711842115 | bibcode = 2018PNAS..115.6506B | doi-access = free }}</ref>

===Hybrids===
{{Main|Hybrid (biology)}}
{{Multiple image
|image1=Equus quagga quagga, coloured.jpg
|image2=Rau Quagga on Devils Peak.jpg
|width=200
|footer=A true [[quagga]], 1870 (left) vs. a [[Quagga Project|bred-back quagga]], 2014 (right)
}}

Hybrids are offspring resulting from the breeding of two genetically distinct individuals, which usually will result in a high degree of heterozygosity, though hybrid and heterozygous are not synonymous. The deliberate or accidental hybridising of two or more species of closely related animals through captive breeding is a human activity which has been in existence for millennia and has grown for economic purposes.<ref>{{cite book | vauthors = Price E |year=2008 |title=Principles and applications of domestic animal behavior: an introductory text |publisher=Cambridge University Press |url={{Google books|plainurl=yes|id=Ww07sIWTYAAC|page=228}}|location=Sacramento |isbn=978-1-84593-398-2|oclc=226038028}}</ref> Hybrids between different subspecies within a species (such as between the [[Bengal tiger]] and [[Siberian tiger]]) are known as intra-specific hybrids. Hybrids between different species within the same genus (such as between lions and tigers) are known as interspecific hybrids or crosses. Hybrids between different genera (such as between sheep and goats) are known as intergeneric hybrids.<ref>{{cite book|url={{Google books |plainurl=yes |id=O3M4qfxtGhIC|page=13}} |location=Heidelberg | vauthors = Taupitz J, Weschka M |year=2009|title=Chimbrids – Chimeras and Hybrids in Comparative European and International Research |publisher=Springer |page=13 |isbn=978-3-540-93869-9 |oclc=495479133}}</ref> Natural hybrids will occur in [[hybrid zone]]s, where two populations of species within the same genera or species living in the same or adjacent areas will interbreed with each other. Some hybrids have been recognised as species, such as the [[red wolf]] (though this is controversial).<ref>{{cite journal |title=An account of the taxonomy of North American wolves from morphological and genetic analyses |year=2012 |journal=North American Fauna |volume=77 |page=2 |doi=10.3996/nafa.77.0001 |vauthors=Chambers SM, Fain SR, Fazio B, Amaral M |url=https://digital.library.unt.edu/ark:/67531/metadc700981/ |doi-access=free |access-date=12 October 2019 |archive-date=31 May 2021 |archive-url=https://web.archive.org/web/20210531050233/https://digital.library.unt.edu/ark:/67531/metadc700981/ |url-status=live }}</ref>

[[Artificial selection]], the deliberate [[selective breeding]] of domestic animals, is being used to [[breeding back|breed back]] [[Holocene extinction|recently extinct]] animals in an attempt to achieve an animal breed with a [[phenotype]] that resembles that extinct [[wildtype]] ancestor. A breeding-back (intraspecific) hybrid may be very similar to the extinct wildtype in appearance, ecological niche and to some extent genetics, but the initial [[gene pool]] of that wild type is lost forever with its [[extinction]]. As a result, bred-back breeds are at best vague look-alikes of extinct wildtypes, as [[Heck cattle]] are of the [[aurochs]].<ref name="vanVuure">{{cite book | vauthors = van Vuure T |title=Retracing the Aurochs – History, Morphology and Ecology of an extinct wild Ox |year=2005 |isbn=978-954-642-235-4 |publisher=Pensoft Publishers |oclc=940879282}}</ref>

[[Purebred]] wild species evolved to a specific ecology can be threatened with extinction<ref>{{cite journal | vauthors = Mooney HA, Cleland EE | title = The evolutionary impact of invasive species | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 98 | issue = 10 | pages = 5446–5451 | date = May 2001 | pmid = 11344292 | pmc = 33232 | doi = 10.1073/pnas.091093398 | bibcode = 2001PNAS...98.5446M | doi-access = free }}</ref> through the process of [[genetic pollution]], the uncontrolled hybridisation, [[introgression]] genetic swamping which leads to homogenisation or [[Fitness (biology)|out-competition]] from the [[heterosis|heterosic]] hybrid species.<ref>{{cite journal | vauthors = Le Roux JJ, Foxcroft LC, Herbst M, MacFadyen S | title = Genetic analysis shows low levels of hybridization between African wildcats (Felis silvestris lybica) and domestic cats (F. s. catus) in South Africa | journal = Ecology and Evolution | volume = 5 | issue = 2 | pages = 288–299 | date = January 2015 | pmid = 25691958 | pmc = 4314262 | doi = 10.1002/ece3.1275| bibcode = 2015EcoEv...5..288L }}</ref> When new populations are imported or selectively bred by people, or when habitat modification brings previously isolated species into contact, extinction in some species, especially rare varieties, is possible.<ref>{{cite book| vauthors = Wilson A |title= Australia's state of the forests report |page=107 |year=2003}}</ref> [[Interbreeding]] can swamp the rarer gene pool and create hybrids, depleting the purebred gene pool. For example, the endangered [[wild water buffalo]] is most threatened with extinction by genetic pollution from the [[Water buffalo|domestic water buffalo]]. Such extinctions are not always apparent from a [[morphology (biology)|morphological]] standpoint. Some degree of [[gene flow]] is a normal evolutionary process, nevertheless, hybridisation threatens the existence of rare species.<ref>{{cite journal |title= Extinction by Hybridization and Introgression | vauthors = Rhymer JM, Simberloff D |journal = Annual Review of Ecology and Systematics |date=November 1996 |volume= 27 | issue = 1 |pages= 83–109 |doi= 10.1146/annurev.ecolsys.27.1.83 | bibcode = 1996AnRES..27...83R }}</ref><ref>{{cite book | vauthors = Potts BM | veditors = Barbour RC, Hingston AB |year=2001 |title=Genetic pollution from farm forestry using eucalypt species and hybrids: a report for the RIRDC/L&WA/FWPRDC Joint Venture Agroforestry Program |publisher= Rural Industrial Research and Development Corporation of Australia|isbn= 978-0-642-58336-9|oclc=48794104}}</ref>

===Threats===
{{See also|Holocene extinction}}
[[File:Extinctions Africa Austrailia NAmerica Madagascar.gif|thumb|upright=1.4|Biodiversity of large mammal species per continent before and after humans arrived there]]

The loss of species from ecological communities, [[defaunation]], is primarily driven by human activity.<ref name=dirzo/> This has resulted in [[empty forest]]s, ecological communities depleted of large vertebrates.<ref name=primack2014>{{Cite book|title=Essentials of Conservation Biology | vauthors = Primack R |publisher=Sinauer Associates, Inc. Publishers |year=2014 |isbn=978-1-60535-289-3 |location=Sunderland, MA |pages=217–245 |edition=6th |oclc=876140621}}</ref><ref>{{cite journal | vauthors = Vignieri S | title = Vanishing fauna. Introduction | journal = Science | volume = 345 | issue = 6195 | pages = 392–395 | date = July 2014 | pmid = 25061199 | doi = 10.1126/science.345.6195.392 | doi-access = free | bibcode = 2014Sci...345..392V }}</ref> In the [[Quaternary extinction event]], the mass die-off of [[megafauna]]l variety coincided with the appearance of humans, suggesting a human influence. One hypothesis is that humans hunted large mammals, such as the [[woolly mammoth]], into extinction.<ref>{{cite journal | vauthors = Burney DA, Flannery TF | title = Fifty millennia of catastrophic extinctions after human contact | journal = Trends in Ecology & Evolution | volume = 20 | issue = 7 | pages = 395–401 | date = July 2005 | pmid = 16701402 | doi = 10.1016/j.tree.2005.04.022 | url = https://www.anthropology.hawaii.edu/Fieldschools/Kauai/Publications/Publication%204.pdf | url-status = dead | archive-url = https://web.archive.org/web/20100610061434/http://www.anthropology.hawaii.edu/Fieldschools/Kauai/Publications/Publication%204.pdf | archive-date = 10 June 2010 }}</ref><ref>{{cite book | vauthors = Diamond J | year=1984 |chapter=Historic extinctions: a Rosetta stone for understanding prehistoric extinctions |title=Quaternary extinctions: A prehistoric revolution | veditors = Martin PS, Klein RG | pages=824–862 | location=Tucson| publisher=University of Arizona Press | isbn=978-0-8165-1100-6|oclc=10301944}}</ref> The 2019 ''[[Global Assessment Report on Biodiversity and Ecosystem Services]]'' by [[IPBES]] states that the total [[Biomass (ecology)|biomass]] of wild mammals has declined by 82 per cent since the beginning of human civilisation.<ref>{{cite news |vauthors=Watts J |date=6 May 2019 |title=Human society under urgent threat from loss of Earth's natural life |url=https://www.theguardian.com/environment/2019/may/06/human-society-under-urgent-threat-loss-earth-natural-life-un-report |work=[[The Guardian]] |access-date=1 July 2019 |archive-date=14 June 2019 |archive-url=https://web.archive.org/web/20190614160705/https://www.theguardian.com/environment/2019/may/06/human-society-under-urgent-threat-loss-earth-natural-life-un-report |url-status=live }}</ref><ref>{{cite news|vauthors=McGrath M|date=6 May 2019|title=Nature crisis: Humans 'threaten 1m species with extinction'|url=https://www.bbc.com/news/science-environment-48169783|work=[[BBC]]|access-date=1 July 2019|archive-date=30 June 2019|archive-url=https://web.archive.org/web/20190630044916/https://www.bbc.com/news/science-environment-48169783|url-status=live}}</ref> Wild animals make up just 4% of mammalian [[biomass (ecology)|biomass]] on earth, while humans and their domesticated animals make up 96%.<ref name="Bar-On_2018"/>

Various species are predicted to [[list of critically endangered species|become extinct in the near future]],<ref>{{cite web | vauthors = Main D | url = https://www.livescience.com/41421-animals-threatened-with-extinction.html | title = 7 Iconic Animals Humans Are Driving to Extinction | work = [[Live Science]] | date = 22 November 2013 | access-date = 25 January 2024 | archive-date = 6 January 2023 | archive-url = https://web.archive.org/web/20230106233208/https://www.livescience.com/41421-animals-threatened-with-extinction.html | url-status = live }}</ref> among them the [[rhinoceros]],<ref>{{cite web | url = https://blogs.scientificamerican.com/extinction-countdown/2011/10/25/poachers-drive-javan-rhino-to-extinction-in-vietnam/ | archive-url = https://web.archive.org/web/20150406103742/http://blogs.scientificamerican.com/extinction-countdown/2011/10/25/poachers-drive-javan-rhino-to-extinction-in-vietnam/ | archive-date = 6 April 2015 | title = Poachers Drive Javan Rhino to Extinction in Vietnam | vauthors = Platt JR | date = 25 October 2011 | publisher = [[Scientific American]] }}</ref> [[giraffe]]s,<ref>{{Cite news |url=https://www.theguardian.com/environment/2016/dec/08/giraffe-red-list-vulnerable-species-extinction |title=Giraffes facing extinction after devastating decline, experts warn |vauthors=Carrington D |date=8 December 2016 |newspaper=The Guardian |access-date=4 February 2017 |archive-date=13 August 2021 |archive-url=https://web.archive.org/web/20210813122004/https://www.theguardian.com/environment/2016/dec/08/giraffe-red-list-vulnerable-species-extinction |url-status=live }}</ref> and species of [[primate]]s<ref name="primates">{{cite journal | vauthors = Estrada A, Garber PA, Rylands AB, Roos C, Fernandez-Duque E, Di Fiore A, Nekaris KA, Nijman V, Heymann EW, Lambert JE, Rovero F, Barelli C, Setchell JM, Gillespie TR, Mittermeier RA, Arregoitia LV, de Guinea M, Gouveia S, Dobrovolski R, Shanee S, Shanee N, Boyle SA, Fuentes A, MacKinnon KC, Amato KR, Meyer AL, Wich S, Sussman RW, Pan R, Kone I, Li B | display-authors = 6 | title = Impending extinction crisis of the world's primates: Why primates matter | journal = Science Advances | volume = 3 | issue = 1 | pages = e1600946 | date = January 2017 | pmid = 28116351 | pmc = 5242557 | doi = 10.1126/sciadv.1600946 | bibcode = 2017SciA....3E0946E }}</ref> and [[pangolin]]s.<ref>{{Cite news |url=https://www.telegraph.co.uk/news/earth/wildlife/11370277/Pangolins-why-this-cute-prehistoric-mammal-is-facing-extinction.html |archive-url=https://ghostarchive.org/archive/20220110/https://www.telegraph.co.uk/news/earth/wildlife/11370277/Pangolins-why-this-cute-prehistoric-mammal-is-facing-extinction.html |archive-date=10 January 2022 |url-access=subscription |url-status=live |title=Pangolins: why this cute prehistoric mammal is facing extinction| vauthors = Fletcher M |date=31 January 2015 |work=The Telegraph}}{{cbignore}}</ref> According to the WWF's 2020 ''[[Living Planet Report]]'', vertebrate [[wildlife]] populations have declined by 68% since 1970 as a result of human activities, particularly [[overconsumption]], [[population growth]] and [[intensive farming]], which is evidence that humans have triggered a [[sixth mass extinction]] event.<ref>{{cite news |vauthors=Greenfield P |date=9 September 2020 |title=Humans exploiting and destroying nature on unprecedented scale – report |url=https://www.theguardian.com/environment/2020/sep/10/humans-exploiting-and-destroying-nature-on-unprecedented-scale-report-aoe |work=[[The Guardian]] |access-date=13 October 2020 |archive-date=21 October 2021 |archive-url=https://web.archive.org/web/20211021225045/https://www.theguardian.com/environment/2020/sep/10/humans-exploiting-and-destroying-nature-on-unprecedented-scale-report-aoe |url-status=live }}</ref><ref>{{cite news |vauthors=McCarthy D |date=1 October 2020 |title=Terrifying wildlife losses show the extinction end game has begun – but it's not too late for change |url=https://www.independent.co.uk/voices/wildlife-loss-humans-population-agriculture-extinction-b738367.html |work=The Independent |access-date=13 October 2020 |archive-date=7 April 2023 |archive-url=https://web.archive.org/web/20230407003854/https://www.independent.co.uk/voices/wildlife-loss-humans-population-agriculture-extinction-b738367.html |url-status=live }}</ref> Hunting alone threatens hundreds of mammalian species around the world.<ref>{{cite web |url=https://www.science.org/content/article/people-are-hunting-primates-bats-and-other-mammals-extinction |title=People are hunting primates, bats, and other mammals to extinction |vauthors=Pennisi E |author-link=Elizabeth Pennisi |date=18 October 2016 |work=[[Science (magazine)|Science]] |access-date=3 February 2017 |archive-date=20 October 2021 |archive-url=https://web.archive.org/web/20211020025827/https://www.science.org/content/article/people-are-hunting-primates-bats-and-other-mammals-extinction |url-status=live }}</ref><ref>{{cite journal | vauthors = Ripple WJ, Abernethy K, Betts MG, Chapron G, Dirzo R, Galetti M, Levi T, Lindsey PA, Macdonald DW, Machovina B, Newsome TM, Peres CA, Wallach AD, Wolf C, Young H | display-authors = 6 | title = Bushmeat hunting and extinction risk to the world's mammals | journal = Royal Society Open Science | volume = 3 | issue = 10 | pages = 160498 | date = October 2016 | pmid = 27853564 | pmc = 5098989 | doi = 10.1098/rsos.160498 | bibcode = 2016RSOS....360498R | hdl = 1893/24446 }}</ref> Scientists claim that the growing demand for [[meat]] is contributing to [[biodiversity loss]] as this is a significant driver of [[deforestation]] and [[habitat destruction]]; species-rich habitats, such as significant portions of the [[Amazon rainforest]], are being converted to agricultural land for meat production.<ref>{{cite journal | vauthors = Williams M, Zalasiewicz J, Haff PK, Schwägerl C, Barnosky AD, Ellis EC |author-link5=Anthony David Barnosky |year=2015 |title=The Anthropocene Biosphere |journal=The Anthropocene Review |volume=2 |issue=3 |pages=196–219 |doi=10.1177/2053019615591020|bibcode=2015AntRv...2..196W |s2cid=7771527 }}</ref><ref>{{cite web |url=https://www.science.org/content/article/meat-eaters-may-speed-worldwide-species-extinction-study-warns |title=Meat-eaters may speed worldwide species extinction, study warns |vauthors=Morell V |date=11 August 2015 |work=[[Science (magazine)|Science]] |access-date=3 February 2017 |archive-date=20 December 2016 |archive-url=https://web.archive.org/web/20161220105327/http://www.sciencemag.org/news/2015/08/meat-eaters-may-speed-worldwide-species-extinction-study-warns |url-status=live }}</ref><ref>{{cite journal | vauthors = Machovina B, Feeley KJ, Ripple WJ | title = Biodiversity conservation: The key is reducing meat consumption | journal = The Science of the Total Environment | volume = 536 | pages = 419–431 | date = December 2015 | pmid = 26231772 | doi = 10.1016/j.scitotenv.2015.07.022 | bibcode = 2015ScTEn.536..419M }}</ref> Another influence is over-hunting and [[species affected by poaching|poaching]], which can reduce the overall population of game animals,<ref>{{cite journal |vauthors=Redford KH |year=1992 |title=The empty forest |journal=BioScience |volume=42 |issue=6 |pages=412–422 |url=http://www.dse.ufpb.br/alexandre/Redford%201992%20-The%20empty%20forest.pdf |doi=10.2307/1311860 |jstor=1311860 |access-date=4 February 2017 |archive-date=28 February 2021 |archive-url=https://web.archive.org/web/20210228092214/http://www.dse.ufpb.br/alexandre/Redford%201992%20-The%20empty%20forest.pdf |url-status=live }}</ref> especially those located near villages,<ref name=peres2006>{{cite book| vauthors = Peres CA, Nascimento HS |title=Human Exploitation and Biodiversity Conservation |chapter=Impact of game hunting by the Kayapó of south-eastern Amazonia: implications for wildlife conservation in tropical forest indigenous reserves |volume=3 |issue=8 |year=2006 |pages=287–313 |publisher=Springer |isbn=978-1-4020-5283-5 |oclc=207259298}}</ref> as in the case of [[peccary|peccaries]].<ref>{{cite journal | vauthors = Altrichter M, Boaglio G |title=Distribution and Relative Abundance of Peccaries in the Argentine Chaco: Associations with Human Factors | journal=Biological Conservation |volume=116 |issue=2 |year=2004 |pages=217–225 |doi=10.1016/S0006-3207(03)00192-7|bibcode=2004BCons.116..217A }}</ref> The effects of poaching can especially be seen in the [[ivory trade]] with African elephants.<ref>{{cite web |vauthors=Gobush K |title=Effects of Poaching on African elephants |url=https://conservationbiology.uw.edu/research-programs/effects-of-poaching-on-african-elephants/ |website=Center For Conservation Biology |publisher=University of Washington |access-date=12 May 2021 |archive-date=8 December 2021 |archive-url=https://web.archive.org/web/20211208132610/https://conservationbiology.uw.edu/research-programs/effects-of-poaching-on-african-elephants/ |url-status=live }}</ref> Marine mammals are at risk from entanglement from fishing gear, notably [[Cetacean bycatch|cetaceans]], with discard mortalities ranging from 65,000 to 86,000 individuals annually.<ref>{{cite book |chapter-url=https://www.fao.org/docrep/003/t4890e/T4890E03.htm#ch1.1.10 |chapter=Bycatch of Marine Mammals |title=A global assessment of fisheries bycatch and discards |vauthors=Alverson DL, Freeburg MH, Murawski SA, Pope JG |year=1996 |orig-year=1994 |publisher=Food and Agriculture Organization of the United Nations |location=Rome |isbn=978-92-5-103555-9 |oclc=31424005 |access-date=25 January 2024 |archive-date=17 February 2019 |archive-url=https://web.archive.org/web/20190217074707/http://www.fao.org/docrep/003/T4890E/T4890E03.htm#ch1.1.10 |url-status=live }}</ref>

Attention is being given to endangered species globally, notably through the [[Convention on Biological Diversity]], otherwise known as the Rio Accord, which includes 189 signatory countries that are focused on identifying endangered species and habitats.<ref>{{cite book | vauthors = Glowka L, Burhenne-Guilmin F, Synge HM, McNeely JA, Gündling L |title=IUCN environmental policy and law paper |series=Guide to the Convention on Biodiversity |year=1994 |publisher=International Union for Conservation of Nature |isbn=978-2-8317-0222-3 |oclc=32201845}}</ref> Another notable conservation organisation is the IUCN, which has a membership of over 1,200 governmental and [[Non-governmental organization|non-governmental]] organisations.<ref>{{cite web |url=https://www.iucn.org/about |title=About IUCN |publisher=International Union for Conservation of Nature |access-date=3 February 2017 |date=3 December 2014 |archive-date=15 April 2020 |archive-url=https://web.archive.org/web/20200415031632/https://www.iucn.org/about/ |url-status=live }}</ref>

[[List of recently extinct mammals|Recent extinctions]] can be directly attributed to human influences.<ref name=ceballos>{{cite journal | vauthors = Ceballos G, Ehrlich PR, Barnosky AD, García A, Pringle RM, Palmer TM | title = Accelerated modern human-induced species losses: Entering the sixth mass extinction | journal = Science Advances | volume = 1 | issue = 5 | pages = e1400253 | date = June 2015 | pmid = 26601195 | pmc = 4640606 | doi = 10.1126/sciadv.1400253 | bibcode = 2015SciA....1E0253C }}</ref><ref name=dirzo>{{cite journal | vauthors = Dirzo R, Young HS, Galetti M, Ceballos G, Isaac NJ, Collen B | title = Defaunation in the Anthropocene | journal = Science | volume = 345 | issue = 6195 | pages = 401–406 | date = July 2014 | pmid = 25061202 | doi = 10.1126/science.1251817 | url = https://www.uv.mx/personal/tcarmona/files/2010/08/Science-2014-Dirzo-401-6-2.pdf | bibcode = 2014Sci...345..401D | s2cid = 206555761 | access-date = 25 January 2024 | archive-date = 7 August 2019 | archive-url = https://web.archive.org/web/20190807115621/https://www.uv.mx/personal/tcarmona/files/2010/08/Science-2014-Dirzo-401-6-2.pdf | url-status = live }}</ref> The IUCN characterises 'recent' extinction as those that have occurred past the cut-off point of 1500,<ref>{{cite journal | vauthors = Fisher DO, Blomberg SP | title = Correlates of rediscovery and the detectability of extinction in mammals | journal = Proceedings. Biological Sciences | volume = 278 | issue = 1708 | pages = 1090–1097 | date = April 2011 | pmid = 20880890 | pmc = 3049027 | doi = 10.1098/rspb.2010.1579 }}</ref> and around 80 mammal species have gone extinct since that time and 2015.<ref>{{cite book| vauthors = Ceballos G, Ehrlich AH, Ehrlich PR |year=2015|title=The Annihilation of Nature: Human Extinction of Birds and Mammals |location=Baltimore |publisher=Johns Hopkins University Press |isbn=978-1-4214-1718-9 |page=69}}</ref> Some species, such as the [[Père David's deer]]<ref>{{cite iucn |author=Jiang, Z. |author2=Harris, R.B. |date=2016 |title=''Elaphurus davidianus'' |volume=2016 |page=e.T7121A22159785 |doi=10.2305/IUCN.UK.2016-2.RLTS.T7121A22159785.en |access-date=12 November 2021}}</ref> are [[extinct in the wild]], and survive solely in captive populations. Other species, such as the [[Florida panther]], are [[Ecological extinction|ecologically extinct]], surviving in such low numbers that they essentially have no impact on the ecosystem.<ref name=mckinney2013>{{cite book |chapter-url={{Google books|plainurl=yes |id=hBntufCOxAsC |page=318}} | vauthors = McKinney ML, Schoch R, Yonavjak L |year=2013 |title=Environmental Science: Systems and Solutions|edition=5th|chapter=Conserving Biological Resources |publisher=Jones & Bartlett Learning|isbn=978-1-4496-6139-7|oclc=777948078}}</ref>{{rp|318}} Other populations are only [[Local extinction|locally extinct]] (extirpated), still existing elsewhere, but reduced in distribution,<ref name=mckinney2013/>{{rp|75–77}} as with the extinction of [[grey whale]]s in the [[Atlantic Ocean|Atlantic]].<ref>{{Cite book |title=Encyclopedia of marine mammals |page=404 |year=2009 |publisher=Academic Press |isbn=978-0-12-373553-9 | vauthors = Perrin WF, Würsig BF, Thewissen JG | author-link3 = Hans Thewissen |oclc=455328678}}</ref>