Coat patterns
Cat coat genetics can produce a variety of coat patterns. Some of the most common are:
Bicolor, Tuxedo and Van
This pattern varies between the tuxedo cat which is mostly black with a white chest, and possibly markings on the face and paws/legs, all the way to the Van pattern (so named after the Lake Van area in Turkey, which gave rise to the Turkish Van breed), where the only colored parts of the cat are the tail (usually including the base of the tail proper), and the top of the head (often including the ears). There are several other terms for amounts of white between these two extremes, such as Harlequin or jellicle cat. Bicolor cats can have as their primary (non-white) color black, red, any dilution thereof and tortoiseshell (see below for definition).
Tabby Cat
Striped, with a variety of patterns. The classic "blotched" tabby (or "marbled") pattern is the most common and consists of butterflies and bullseyes. The "mackerel" or "striped" tabby is a series of vertical stripes down the cat's side (resembling the fish). This pattern broken into spots is referred to as a "spotted" tabby. Finally, the tabby markings may look like a series of ticks on the fur, thus the "ticked" tabby, which is almost exclusively associated with the Abyssinian breed of cats. The worldwide evolution of the cat means that certain types of tabby are associated with certain countries; for instance, blotched tabbies are quite rare outside NW Europe, where they are the most common type.
Tortoiseshell
This cat is also known as a Calimanco cat or Clouded Tiger cat, and by the nickname "tortie." In the cat fancy, a tortoiseshell cat is randomly patched over with red (or its dilute form, cream) and black (or its dilute blue) mottled throughout the coat. Additionally, the cat may have white spots in its fur, which make it a "tortoiseshell and white" cat or, if there is a significant amount of white in the fur and the red and black colors form a patchwork rather than a mottled aspect, the cat will be called a "calico." All calicos are tortoiseshell (as they carry both black and red), but not all tortoiseshells are calicos (which requires a significant amount of white in the fur and patching rather than mottling of the colors). The calico is also sometimes called a "tricolor cat." The Japanese refer to this pattern as mi-ke (meaning "triple fur"), while the Dutch call these cats lapjeskat (meaning "patches cat"). A true tricolor must consist of three colors: a reddish color, dark or light; white; and one other color, typically a brown, black or blue.Both tortoiseshell and calico cats are typically female because the coat pattern is the result of differential X chromosome inactivation in females (which, as with all normal female mammals, have two X chromosomes). Conversely, cats where the overall color is ginger (orange) are commonly male (roughly in a 3:1 ratio). In a litter sired by a ginger tom, the females will be tortoiseshell or ginger. Male tortoiseshells can occur as a result of chromosomal abnormalities (often linked to sterility) or by a phenomenon known as chimericism, where two early stage embryos are merged into a single kitten.
Siamese cat
The colorpoint pattern is most commonly associated with Siamese cats, but may also appear in any domesticated cat. A colorpointed cat has dark colors on the face, ears, feet, and tail, with a lighter version of the same color on the rest of the body, and possibly some white. The exact name of the colorpoint pattern depends on the actual color, so there are seal points (dark brown), chocolate points (warm lighter brown), blue points (dark gray), lilac or frost points (silvery gray-pink), red or flame points (orange), and tortie (tortoiseshell mottling) points, among others. This pattern is the result of a temperature sensitive mutation in one of the enzymes in the metabolic pathway from tyrosine to pigment, such as melanin; thus, little or no pigment is produced except in the extremities or "points," where the skin is slightly cooler. For this reason, colorpointed cats tend to darken with age as bodily temperature drops; also, the fur over a significant injury may sometimes darken or lighten as a result of temperature change.
The tyrosine pathway also produces neurotransmitters, thus mutations in the early parts of that pathway may affect not only pigment, but also neurological development. This results in a higher frequency of cross-eyes among colorpointed cats, as well as the high frequency of cross-eyes in white tigers.
Cat coat genetics can produce a variety of coat patterns. Some of the most common are:
Bicolor, Tuxedo and Van
This pattern varies between the tuxedo cat which is mostly black with a white chest, and possibly markings on the face and paws/legs, all the way to the Van pattern (so named after the Lake Van area in Turkey, which gave rise to the Turkish Van breed), where the only colored parts of the cat are the tail (usually including the base of the tail proper), and the top of the head (often including the ears). There are several other terms for amounts of white between these two extremes, such as Harlequin or jellicle cat. Bicolor cats can have as their primary (non-white) color black, red, any dilution thereof and tortoiseshell (see below for definition).
Tabby Cat
Striped, with a variety of patterns. The classic "blotched" tabby (or "marbled") pattern is the most common and consists of butterflies and bullseyes. The "mackerel" or "striped" tabby is a series of vertical stripes down the cat's side (resembling the fish). This pattern broken into spots is referred to as a "spotted" tabby. Finally, the tabby markings may look like a series of ticks on the fur, thus the "ticked" tabby, which is almost exclusively associated with the Abyssinian breed of cats. The worldwide evolution of the cat means that certain types of tabby are associated with certain countries; for instance, blotched tabbies are quite rare outside NW Europe, where they are the most common type.
Tortoiseshell
This cat is also known as a Calimanco cat or Clouded Tiger cat, and by the nickname "tortie." In the cat fancy, a tortoiseshell cat is randomly patched over with red (or its dilute form, cream) and black (or its dilute blue) mottled throughout the coat. Additionally, the cat may have white spots in its fur, which make it a "tortoiseshell and white" cat or, if there is a significant amount of white in the fur and the red and black colors form a patchwork rather than a mottled aspect, the cat will be called a "calico." All calicos are tortoiseshell (as they carry both black and red), but not all tortoiseshells are calicos (which requires a significant amount of white in the fur and patching rather than mottling of the colors). The calico is also sometimes called a "tricolor cat." The Japanese refer to this pattern as mi-ke (meaning "triple fur"), while the Dutch call these cats lapjeskat (meaning "patches cat"). A true tricolor must consist of three colors: a reddish color, dark or light; white; and one other color, typically a brown, black or blue.Both tortoiseshell and calico cats are typically female because the coat pattern is the result of differential X chromosome inactivation in females (which, as with all normal female mammals, have two X chromosomes). Conversely, cats where the overall color is ginger (orange) are commonly male (roughly in a 3:1 ratio). In a litter sired by a ginger tom, the females will be tortoiseshell or ginger. Male tortoiseshells can occur as a result of chromosomal abnormalities (often linked to sterility) or by a phenomenon known as chimericism, where two early stage embryos are merged into a single kitten.
Siamese cat
The colorpoint pattern is most commonly associated with Siamese cats, but may also appear in any domesticated cat. A colorpointed cat has dark colors on the face, ears, feet, and tail, with a lighter version of the same color on the rest of the body, and possibly some white. The exact name of the colorpoint pattern depends on the actual color, so there are seal points (dark brown), chocolate points (warm lighter brown), blue points (dark gray), lilac or frost points (silvery gray-pink), red or flame points (orange), and tortie (tortoiseshell mottling) points, among others. This pattern is the result of a temperature sensitive mutation in one of the enzymes in the metabolic pathway from tyrosine to pigment, such as melanin; thus, little or no pigment is produced except in the extremities or "points," where the skin is slightly cooler. For this reason, colorpointed cats tend to darken with age as bodily temperature drops; also, the fur over a significant injury may sometimes darken or lighten as a result of temperature change.
The tyrosine pathway also produces neurotransmitters, thus mutations in the early parts of that pathway may affect not only pigment, but also neurological development. This results in a higher frequency of cross-eyes among colorpointed cats, as well as the high frequency of cross-eyes in white tigers.
White cats
True albinism (a mutation of the tyrosinase gene) is quite rare in cats. Much more common is the appearance of white coat color due to a lack of melanocytes in the skin. A higher frequency of deafness in white cats is due to a reduction in the population and survival of melanoblast stem cells, which in addition to creating pigment producing cells, develop into a variety of neurological cell types. White cats with one or two blue eyes have a particularly high likelihood of being deaf.
True albinism (a mutation of the tyrosinase gene) is quite rare in cats. Much more common is the appearance of white coat color due to a lack of melanocytes in the skin. A higher frequency of deafness in white cats is due to a reduction in the population and survival of melanoblast stem cells, which in addition to creating pigment producing cells, develop into a variety of neurological cell types. White cats with one or two blue eyes have a particularly high likelihood of being deaf.
Body types
Cats can also come in several body types, ranging between two extremes:
Cats can also come in several body types, ranging between two extremes:
Oriental
Not a specific breed, but any cat with an elongated slender build, almond-shaped eyes, long nose, large ears (the Siamese and Oriental Shorthair breeds are examples of this).
Not a specific breed, but any cat with an elongated slender build, almond-shaped eyes, long nose, large ears (the Siamese and Oriental Shorthair breeds are examples of this).
Cobby
Any cat with a short, muscular, compact build, roundish eyes, short nose, and small ears. Persian cats and Exotic cats are two prime examples of such a body type.
Feral cats
Feral cats may live alone, but most are found in large groups called feral colonies with communal nurseries, depending on resource availability. Most abandoned cats probably have little alternative to joining a feral colony. Some feral cat colonies are found in large cities such as around the Colosseum and Forum Romanum in Rome. The Roman cats are not truly feral because they are partly fed and vetted by the local authority. Because cats are adaptable, those in residential areas know that if they are friendly to humans they need not worry about food or shelter. Some urban "stray" cats have many houses/humans to support them.
Although cats are adaptable, feral felines are unable to thrive in extreme cold and heat, and with a very high protein requirement, few find adequate nutrition on their own in cities. They are often killed by dogs, coyotes, and automobiles. However, there are thousands of volunteers and organizations that trap these unadoptable feral felines, neutering them, immunize the cats against rabies and feline leukemia, and treat them with long-lasting flea products. Before release back into their feral colonies, the attending veterinarian often nips the tip off one ear to mark the feral as neutered and inoculated, since these cats will more than likely find themselves trapped again. Volunteers continue to feed and give care to these cats throughout their lives, and not only is their lifespan greatly increased, but behavior and nuisance problems, due to competition for food, are also greatly reduced.
Environmental effects
Feral cat
Feral cats are thought to be a major predator of Hawaiian coastal and forest habitats, and are one species among many responsible for the decline of endemic forest bird species as well as seabirds like the Wedge-tailed Shearwater. In one study of 56 cats' feces, the remains of 44 birds were found, 40 of which were endemic species.
In the Southern Hemisphere there are many landmasses including Australia where cat species have never been native, and other placental mammalian predators were rare or absent. Native species there tend to be more ecologically vulnerable and behaviorally "naive" to predation by feral cats. Feral cats have had serious effects on these wildlife species and have played a leading role in the endangerment and extinction of many of them. In Australia a large quantity of native birds, lizards and small marsupials are taken every year by feral cats, and feral cats have played a role in driving some small marsupial species to extinction. Some organizations in Australia are now going to effort of creating fenced islands of habitat for endangered species that are free of feral cats and foxes.
Ethical and humane concerns over feral cats
There are two divergent views about the relationship of cats with the environment. The first argues that the environmental impact of feral cat programs and of indoor/outdoor cats is a subject of debate. Part of this stems from humane concern for the cats, and part stems from concerns about cat predation on endangered species. The amount of ecological damage done by indoor/outdoor cats depends on local conditions. As suggested above, the most severe effect occurs to island ecologies. Environmental concerns may be minimal in most of the UK where cats are an established species and few to none of the local prey species are endangered. Pet owners can contact veterinarians, ecological organizations, and universities for opinions about whether local conditions are suitable for outdoor cats. Additional concerns include potential dangers from larger predators and infectious diseases. Coyotes kill large numbers of housecats in the Southwestern United States, even in urban zones. FELV (feline leukemia), FIV (feline immunodeficiency virus), or rabies may be present in the area. If faced with conflicting evidence, the safe choice is to keep a cat indoors.
Cats present a risk of overpopulation, as well. According to the Humane Society of the United States, 3–4 million cats and dogs are euthanized each year in the United States and many more are confined to cages in shelters because there are significantly more animals being born than there are homes. Neutering pets helps keep the overpopulation down. A study in 1992 found that in the USA, 12,893 (29.4%) of pets, 26.9% of dogs and 32.6% of cats were sterilized. Local humane societies, SPCAs, and other animal protection organizations urge people to neuter their pets and to adopt from shelters instead of purchasing elsewhere.
Any cat with a short, muscular, compact build, roundish eyes, short nose, and small ears. Persian cats and Exotic cats are two prime examples of such a body type.
Feral cats
Feral cats may live alone, but most are found in large groups called feral colonies with communal nurseries, depending on resource availability. Most abandoned cats probably have little alternative to joining a feral colony. Some feral cat colonies are found in large cities such as around the Colosseum and Forum Romanum in Rome. The Roman cats are not truly feral because they are partly fed and vetted by the local authority. Because cats are adaptable, those in residential areas know that if they are friendly to humans they need not worry about food or shelter. Some urban "stray" cats have many houses/humans to support them.
Although cats are adaptable, feral felines are unable to thrive in extreme cold and heat, and with a very high protein requirement, few find adequate nutrition on their own in cities. They are often killed by dogs, coyotes, and automobiles. However, there are thousands of volunteers and organizations that trap these unadoptable feral felines, neutering them, immunize the cats against rabies and feline leukemia, and treat them with long-lasting flea products. Before release back into their feral colonies, the attending veterinarian often nips the tip off one ear to mark the feral as neutered and inoculated, since these cats will more than likely find themselves trapped again. Volunteers continue to feed and give care to these cats throughout their lives, and not only is their lifespan greatly increased, but behavior and nuisance problems, due to competition for food, are also greatly reduced.
Environmental effects
Feral cat
Feral cats are thought to be a major predator of Hawaiian coastal and forest habitats, and are one species among many responsible for the decline of endemic forest bird species as well as seabirds like the Wedge-tailed Shearwater. In one study of 56 cats' feces, the remains of 44 birds were found, 40 of which were endemic species.
In the Southern Hemisphere there are many landmasses including Australia where cat species have never been native, and other placental mammalian predators were rare or absent. Native species there tend to be more ecologically vulnerable and behaviorally "naive" to predation by feral cats. Feral cats have had serious effects on these wildlife species and have played a leading role in the endangerment and extinction of many of them. In Australia a large quantity of native birds, lizards and small marsupials are taken every year by feral cats, and feral cats have played a role in driving some small marsupial species to extinction. Some organizations in Australia are now going to effort of creating fenced islands of habitat for endangered species that are free of feral cats and foxes.
Ethical and humane concerns over feral cats
There are two divergent views about the relationship of cats with the environment. The first argues that the environmental impact of feral cat programs and of indoor/outdoor cats is a subject of debate. Part of this stems from humane concern for the cats, and part stems from concerns about cat predation on endangered species. The amount of ecological damage done by indoor/outdoor cats depends on local conditions. As suggested above, the most severe effect occurs to island ecologies. Environmental concerns may be minimal in most of the UK where cats are an established species and few to none of the local prey species are endangered. Pet owners can contact veterinarians, ecological organizations, and universities for opinions about whether local conditions are suitable for outdoor cats. Additional concerns include potential dangers from larger predators and infectious diseases. Coyotes kill large numbers of housecats in the Southwestern United States, even in urban zones. FELV (feline leukemia), FIV (feline immunodeficiency virus), or rabies may be present in the area. If faced with conflicting evidence, the safe choice is to keep a cat indoors.
Cats present a risk of overpopulation, as well. According to the Humane Society of the United States, 3–4 million cats and dogs are euthanized each year in the United States and many more are confined to cages in shelters because there are significantly more animals being born than there are homes. Neutering pets helps keep the overpopulation down. A study in 1992 found that in the USA, 12,893 (29.4%) of pets, 26.9% of dogs and 32.6% of cats were sterilized. Local humane societies, SPCAs, and other animal protection organizations urge people to neuter their pets and to adopt from shelters instead of purchasing elsewhere.
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