Editing Tiger (section)

== Characteristics ==
[[File:TigerSkelLyd1.png|thumb|left|Tiger skeleton from Royal Natural History Volume 1 (1839)|alt=Drawing of tiger skeleton]]
The tiger has a typical felid morphology, with a muscular body, shortened legs, strong forelimbs with wide front paws, a large head and a tail that is about half the length of the rest of its body.<ref name=Mazak1981/>{{sfn|Sludskii|1992|p=98}} It has five digits, including a [[dewclaw]], on the front feet and four on the back, all of which have retractile claws that are compact and curved, and can reach {{convert|10|cm|in|abbr=on}} long.<ref name=Mazak1981/>{{sfn|Thapar|2004|p=26}} The ears are rounded and the eyes have a round pupil.<ref name=Mazak1981/> The snout ends in a triangular, pink tip with small black dots, the number of which increase with age.<ref>{{cite journal |last1=Zhao|first1=C. |last2=Dai|first2=W. |last3=Liu|first3=Q. |last4=Liu|first4=D. |last5=Roberts |first5=N. J. |last6=Liu |first6=Z. |last7=Gong |first7=M. |last8=Qiu |first8=H. |last9=Liu |first9=C. |last10=Liu |first10=D. |last11=Ma |first11=G. |last12=Jiang |first12=G. |year=2024 |title=Combination of facial and nose features of Amur tigers to determine age|journal=Integrative Zoology |volume=20 |pages=186–198 |doi=10.1111/1749-4877.12817 |pmid=38509845 |name-list-style=amp}}</ref> The tiger's skull is robust, with a constricted front region, proportionally small, elliptical [[Orbit (anatomy)|orbits]], long [[nasal bone]]s and a lengthened [[cranium]] with a large [[sagittal crest]].{{sfn|Sludskii|1992|p=103}}<ref name=Mazak1981/> It resembles a lion's skull, but differs from it in the concave or flattened underside of the lower jaw and in its longer nasals.{{sfn|Sludskii|1992|p=103}}<ref name=Kitchener2009/> The tiger has 30 fairly robust teeth and its somewhat curved [[Canine tooth|canines]] are the longest in the cat family at {{cvt|6.4|–|7.6|cm}}.<ref name=Mazak1981 />{{sfn|Thapar|2004|p=25}}

The tiger has a head-body length of {{cvt|1.4|–|2.8|m}} with a {{cvt|0.6|–|1.1|m}} tail and stands {{cvt|0.8|–|1.1|m}} at the shoulder.<ref name=Walker>{{cite book |author1=Novak, R. M. |author2=Walker, E. P. |name-list-style=amp |year=1999 |chapter=''Panthera tigris'' (tiger) |chapter-url=https://books.google.com/books?id=T37sFCl43E8C&pg=PA825 |title=Walker's Mammals of the World |edition=6th |publisher=Johns Hopkins University Press |location=Baltimore |isbn=978-0-8018-5789-8 |pages=825–828 |access-date=17 October 2020 |archive-date=5 May 2024 |archive-url=https://web.archive.org/web/20240505145513/https://books.google.com/books?id=T37sFCl43E8C&pg=PA825#v=onepage&q&f=false#v=onepage&q&f=false |url-status=bot: unknown }}</ref> The Siberian and Bengal tigers are the largest.<ref name=Mazak1981/> Male Bengal tigers weigh {{cvt|200|–|260|kg}}, and females weigh {{cvt|100|–|160|kg}}; island tigers are the smallest, likely due to [[insular dwarfism]].<ref name=Kitchener1999/> Male Sumatran tigers weigh {{cvt|100|–|140|kg}}, and females weigh {{cvt|75|–|110|kg}}.<ref name=Sunquist2010/> The tiger is popularly thought to be the largest living felid species; but since tigers of the different subspecies and populations vary greatly in size and weight, the tiger's average size may be less than the lion's, while the largest tigers are bigger than their lion counterparts.<ref name=Kitchener2009/>

===Coat===
[[File:Tiger Stripes (29808869755).jpg|thumb|Siberian tiger coat on flank (side)|alt=Close up of a tiger's fur]]
The tiger's coat usually has short hairs, reaching up to {{cvt|35|mm}}, though the hairs of the northern-living Siberian tiger can reach {{cvt|105|mm}}. Belly hairs tend to be longer than back hairs. The density of their fur is usually thin, though the Siberian tiger develops a particularly thick winter coat. The tiger has lines of fur around the face and long whiskers, especially in males.<ref name=Mazak1981/> It has an orange [[animal coloration|colouration]] that varies from yellowish to reddish.{{sfn|Thapar|2004|p=28}} White fur covers the underside, from head to tail, along with the inner surface of the legs and parts of the face.<ref name=Mazak1981 />{{sfn|Sludskii|1992|pp=99–102}} On the back of the ears, it has a prominent white spot, which is surrounded by black.<ref name=Mazak1981 /> The tiger is marked with distinctive black or dark brown stripes, which are uniquely patterned in each individual.<ref name=Mazak1981>{{cite journal |author=Mazák, V. |year=1981 |title=''Panthera tigris'' |journal=Mammalian Species |issue=152 |pages=1–8 |doi=10.2307/3504004 |jstor=3504004 |doi-access=free}}</ref><ref name=Miquelle/> The stripes are mostly vertical, but those on the limbs and forehead are horizontal. They are more concentrated towards the backside and those on the trunk may reach under the belly. The tips of stripes are generally sharp and some may split up or split and fuse again. Tail stripes are thick bands and a black tip marks the end.{{sfn|Sludskii|1992|pp=99–102}}

The tiger is one of only a few striped cat species.<ref>{{cite journal |author1=Allen, W. L. |author2=Cuthill, I. C. |author3=Scott-Samuel, N. E. |author4=Baddeley, R. |year=2010 |title=Why the leopard got its spots: relating pattern development to ecology in felids |journal=Proceedings of the Royal Society B |volume=278 |issue=1710 |pages=1373–1380 |doi=10.1098/rspb.2010.1734 |pmid=20961899 |pmc=3061134 |name-list-style=amp}}</ref> Stripes are advantageous for [[camouflage]] in vegetation with vertical patterns of light and shade, such as trees, reeds and tall grass.<ref name=Miquelle>Miquelle, D. "Tiger" in {{harvnb|MacDonald|2001|pp=18–21}}</ref><ref>{{cite journal|last=Caro |first=T. |year=2005 |title=The adaptive significance of coloration in mammals |journal=BioScience |volume=55 |issue=2|pages=125–136 |doi=10.1641/0006-3568(2005)055[0125:TASOCI]2.0.CO;2}}</ref> This is supported by a [[Fourier analysis]] study showing that the striping patterns line up with their environment.<ref>{{cite journal |last1=Godfrey |first1=D. |last2=Lythgoe |first2=J. N. |last3=Rumball |first3=D. A. |name-list-style=amp |year=1987 |title=Zebra stripes and tiger stripes: the spatial frequency distribution of the pattern compared to that of the background is significant in display and crypsis |journal=[[Biological Journal of the Linnean Society]] |volume=32 |issue=4 |pages=427–433 |doi=10.1111/j.1095-8312.1987.tb00442.x}}</ref>
The orange colour may also aid in concealment, as the tiger's prey is [[Color blindness|colour blind]] and possibly perceives the tiger as green and blended in with the vegetation.<ref>{{cite journal |author1=Fennell, J. G. |author2=Talas, L. |author3=Baddeley, R. J. |author4=Cuthill, I. C. |author5=Scott-Samuel, N. E. |name-list-style=amp |year=2019 |title=Optimizing colour for camouflage and visibility using deep learning: the effects of the environment and the observer's visual system |journal=Journal of the Royal Society Interface |volume=16 |issue=154|doi=10.1098/rsif.2019.0183 |doi-access=free |page=20190183 |pmid=31138092 |pmc=6544896}}</ref>

==== Colour variations ====
[[File:White tiger Nandankanan.jpeg|thumb|Pseudo-melanistic [[white tiger]]|alt=White tiger with thickened stripes lying down]]
The three [[Polymorphism (biology)|colour variants]] of Bengal tigers – nearly stripeless snow-white, white and golden – are now virtually non-existent in the wild due to the reduction of wild tiger populations but continue in captive populations. The [[white tiger]] has a white background colour with [[Sepia (color)|sepia]]-brown stripes. The [[golden tiger]] is pale golden with reddish-brown stripes. The snow-white tiger is a morph with extremely faint stripes and a pale sepia-brown ringed tail. White and golden morphs are the result of an [[autosomal recessive trait]] with a white [[Locus (genetics)|locus]] and a [[Cat coat genetics#Wide band factors|wideband]] locus, respectively. The snow-white variation is caused by [[polygene]]s with both white and wideband loci.<ref name=Xu_al2017>{{cite journal |author1=Xu, X. |author2=Dong, G. X. |author3=Schmidt-Küntzel, A. |author4=Zhang, X. L. |author5=Zhuang, Y. |author6=Fang, R. |author7=Sun, X. |author8=Hu, X. S. |author9=Zhang, T. Y. |author10=Yang, H. D. |author11=Zhang, D. L. |author12=Marker, L. |author13=Jiang, Z.-F. |author14=Li, R. |author15=Luo, S.-J. |name-list-style=amp |year=2017 |title=The genetics of tiger pelage color variations |journal=Cell Research |volume=27 |issue=7 |pages=954–957 |doi=10.1038/cr.2017.32 |pmid=28281538 |pmc=5518981 |url=https://www.luo-lab.org/publications/Xu17-CellRes-GoldenTiger.pdf |access-date=25 August 2018}}</ref> The breeding of white tigers is controversial, as they have no use for conservation. Only 0.001% of wild tigers have the genes for this colour morph and the overrepresentation of white tigers in captivity is the result of [[inbreeding]]. Hence, their continued breeding will risk both [[inbreeding depression]] and loss of [[genetic variability]] in captive tigers.<ref>{{cite journal |last1=Xavier |first1=N. |year=2010 |title=A new conservation policy needed for reintroduction of Bengal tiger-white |journal=Current Science |volume=99 |issue=7 |pages=894–895 |url=https://www.currentscience.ac.in/Volumes/99/07/0894.pdf |access-date=29 January 2024}}</ref>

Pseudo-[[melanistic]] tigers with thick, merged stripes have been recorded in [[Simlipal National Park]] and three Indian zoos; a [[Population genetics|population genetic]] analysis of Indian tiger samples revealed that this [[phenotype]] is caused by a [[mutation]] of a [[Transmembrane protein|transmembrane]] [[aminopeptidase]] gene. Around 37% of the Simlipal tiger population has this feature, which has been linked to [[genetic isolate|genetic isolation]].<ref>{{cite journal|author=Sagar, V. |name-list-style=amp |author2=Kaelin, C. B. |author3=Natesh, M. |author4=Reddy, P. A. |author5=Mohapatra, R. K. |author6=Chhattani, H. |author7=Thatte, P. |author8=Vaidyanathan, S. |author9=Biswas, S. |author10=Bhatt, S. |author11=Paul, S. |year=2021 |title=High frequency of an otherwise rare phenotype in a small and isolated tiger population |journal=Proceedings of the National Academy of Sciences |volume=118 |issue=39 |page=e2025273118 |doi=10.1073/pnas.2025273118 |pmid=34518374 |pmc=8488692 |bibcode=2021PNAS..11825273S |doi-access=free}}</ref>