Tortoiseshell
Long-haired tortoiseshell DSCF0193.JPG
Information
Alternative Names

Tortoiseshell

Origin

United States

Common Nicknames

Torties

Cat (Felis catus)
List of Cat Breeds



Tortoiseshell (also known as tortie) describes a type of cat coloration [1] found mostly in female cats.[2] It comes in all shades of Brown, with patches of orange or cream and chocolate, black or blue, in a mottled pattern. The term "tortoiseshell" is typically reserved for cats with brindle[3] coats that have relatively few or no white markings, and is named after the material tortoiseshell.

Those that are largely white with red and brown patches are described as tortoiseshell-and-white, in the United Kingdom, or calico in Canada and the United States of America|America.

Torties and calicos are not specific cat breed, but a type of tricolor cat. The tortoiseshell markings appear in many different breeds as well as in non-purebred domestic cats.[4] This pattern is especially preferred in the Japanese Bobtail breed.

Patterns[edit | edit source]

Tortoiseshell cats have coats with patches of red, brown or black, chocolate, cream, or cinnamon. The size of the patches can vary from a fine speckled pattern to large areas of color. Typically, the more white a cat has on their fur, the more solid the patches of color. Dilution genes may modify the coloring, lightening the fur to a mix of cream and blue, lilac or fawn. The markings on tortoiseshell cats are usually asymmetrical. Occasionally Tabby Cat patterns of [5] eumelanin and [6] pheomelanistic colours are also seen (these are often then called "torbie", "torbie" or "caliby"). Tortoiseshell also can be expressed in the point pattern.

Genetics[edit | edit source]

A tortoiseshell cat

Tortoiseshell and calico coats result from an interaction between genetic and developmental factors. The primary gene for coat color (C) is located on the X Chromosome and has two dominant alleles, Orange (XO) and Black (XB), that produce orange phaeomelanin and black eumelanin pigments, respectively. The cells of female cats, which like other mammalian females have two X Chromosome (XX), undergo the phenomenon of X-inactivation, in which one or the other of the X-chromosomes is turned off at random in each cell in very early development. The inactivated X becomes a Barr body Cells in which the chromosome carrying the Orange (XO) allele is inactivated express the alternative Black (XB) allele. Cells in which the Black (XB) allele is inactivated express the Orange (XO) allele. Pigment genes are expressed in melanocytes that migrate to the skin surface later in development. In bi-colored tortoiseshell cats, the melanocytes arrive relatively early, and the two cell types become intermingled, producing the characteristic brindled appearance consisting of an intimate mixture of orange and black cells, with occasional small diffuse spots of orange and black.

Another example of a tortoiseshell cat.

[1][2] A famous calico, Tama In tri-colored calico cats, a second gene interacts developmentally with the coat color gene. This spotting gene produces white, unpigmented patches by delaying the migration of the melanocytes to the skin surface. There are a number of alleles of this gene that produce greater or lesser delays. The amount of white is artificially divided into mitted, bicolor, harlequin, and van, going from almost no white to almost completely white. In the extreme case, no melanocytes make it to the skin and the cat is entirely white (but not an albino). In intermediate cases, melanocyte migration is slowed, so that the pigment cells arrive late in development and have less time to intermingle. Observation of tri-color cats will show that, with a little white color, the orange and black patches become more defined, and with still more white, the patches become completely distinct. Each patch represents a clone of cells derived from one original cell in the early embryo.

Male cats, like other mammalian males, have only a single X chromosome (XY) that does not undergo X-inactivation: coat color is determined by which allele is present on the X, and they will be either entirely black or orange. Very rarely (approximately 1 in 3,000[3]) a male tortoiseshell or calico is born. These animals typically have an extra X chromosome (XXY), a condition known in humans as Klinefelter syndrome, and undergo an inactivation process like that in females. As in humans, these cats are almost always sterile because of the imbalance in sex chromosomes. Some male calico or tortoiseshell cats may be chimeras, which result from the fusion in early development of two embryos with different color genotypes. Others are mosaics, in which the XXY condition arises after conception and the cat is a mixture of cells with different numbers of X chromosomes.

Breeds[edit | edit source]

Folklore[edit | edit source]

Cats of this coloration are believed to bring good luck in the folklore of many cultures.[5] In the United States, these are sometimes referred to as money cats.[6] The Japanese Maneki Neko figurine is almost always a calico cat.

Gallery[edit | edit source]

Trivia[edit | edit source]

  • In looking at a calico cat's skin, one can find evidence of its genetic make up. When the fur is parted, particularly in areas close to the nose and ears, the skin will be multi-colored with darker spots of pigmentation in places where there is darker fur.[4]
  • On October 1, 2001, calico cats were named as the official state cat of Maryland.

References[edit | edit source]

This page uses Creative Commons Licensed content from Wikipedia (view authors). Wikipedia.png

Navigation[edit | edit source]

view · talk · edit Cats Navigation
Felinology Cat AnatomyCat GeneticsCat Coat Genetics • (Bicolor CatBlack CatCalicoDeaf White CatTabby CatTortoiseshell) • Dwarf CatsKittenOdd-Eyed CatSquitten
Cat Health AnesthesiaCat Skin DisordersDeclawingDietFeline AcneFeline AsthmaFeline CalicivirusFeline Hepatic LipidosisFeline Hypertrophic CardiomyopathyFeline Immunodeficiency VirusFeline Infectious PeritonitisFeline Leukemia VirusFeline Lower Urinary Tract DiseaseFeline PanleukopeniaFeline Viral RhinotracheitisFeline VaccinationFleaHeartwormNeuteringPolydactyl CatRabiesRingwormSpayingRoundwormTickToxoplasmosis
Cat Behavior Cat Body LanguageCat FightCatnip (Nepeta Cataria)CommunicationKneading
IntelligenceCat Plays and ToysPuppy CatPurrRighting reflexSenses
Cat Supplies Cat FoodCat ToysCat TreeLitter BoxScratching Post
Human - Feline Interaction
Early Interactions Cats in Ancient EgyptCultural Depictions of CatsFarm CatFeral CatShip's Cat
Cat Registry Cat showAmerican Association of Cat EnthusiastsAmerican Cat Fanciers Association
Cat Aficionado AssociationCat Fanciers' AssociationFédération Internationale Féline
Governing Council of the Cat FancyThe International Cat Association
Canadian Cat Association
Breed Full list
Domestic AbyssinianAegean catAmerican BobtailAmerican CurlAmerican Shorthair
American WirehairArabian MauAustralian MistBalineseBambinoBritish Shorthair
BirmanBombayBurmeseCalifornia Spangled CatChartreuxColorpoint Shorthair
Cornish RexCymricCyprus catDevon RexDonskoyEgyptian MauExotic Shorthair
German RexHavana BrownHimalayanJapanese BobtailJavaneseKhao Manee
KinkalowKoratKurilian BobtailLaPermLykoiMaine CoonManxMunchkin
NebelungNeva MasqueradeNorwegian Forest CatOcicat
Oriental LonghairOriental ShorthairPersianPeterbaldPixie-bobRagdoll
RagamuffinRussian BlueScottish FoldSelkirk RexSiameseSiberian
SingapuraSokokeSnowshoeSomaliSphynxThaiTraditional Persian
TonkineseTurkish AngoraTurkish Van
Hybrid BengalChausieCheetohJungle CurlSavannahSerengeti
Wild Cats
Pantherinae Amur LeopardArabian LeopardBlack PantherClouded LeopardJaguarLeopardLionTiger
Felinae African Golden CatAfrican WildcatAndean Mountain CatAsiatic Golden CatBay Cat
Black-Footed CatBobcatCanada LynxCaracalCheetahChinese Desert CatCougar
Eurasian LynxEuropean WildcatFishing CatFlat-headed CatGeoffroy's Cat
Iberian LynxJaguarundiJungle CatLeopard CatKodkodMarbled CatMargay
OcelotOncillaPampas CatPallas CatRusty-spotted CatSand Cat
ServalSouthern TigrinaSunda Leopard Cat
CategoryPortal
Community content is available under CC-BY-SA unless otherwise noted.