Agouti is a type of

fur Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket t ...

coloration in which each

hair Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and f ...

displays two or more bands of

pigmentation A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compo ...

. The overall appearance of agouti fur is usually

gray Grey (more common in British English) or gray (more common in American English) is an intermediate color between black and white. It is a neutral or achromatic color, meaning literally that it is "without color", because it can be composed o ...

or dull

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model used ...

, although dull

yellow Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the R ...

is also possible. Agouti fur is characterized by an appearance of being composed of hairs of different colors, separate from definite markings (although agouti can appear in combination with other markings, such as spots, stripes or patches). This effect is caused by different ''portions'' of each hair being visible, such that different colors of the hair's banding is seen, despite hairs actually having similar coloration. This effect produces a very distinctive, finely "speckled" appearance similar to "salt and pepper" hair, as well as an

iridescent Iridescence (also known as goniochromism) is the phenomenon of certain surfaces that appear to gradually change color as the angle of view or the angle of illumination changes. Examples of iridescence include soap bubbles, feathers, butterfl ...

effect very similar to

shot silk Shot silk (also called changeant, changeable silk, changeable taffeta, cross-color, changeable fabric, or "dhoop chaon" ("sunshine shade")) is a fabric which is made up of silk woven from warp and weft yarns of two or more colours producing an ...

which causes the overall color to appear to shift subtly depending on the angle of the light or when the animal moves. Agouti fur is the

wild type The wild type (WT) is the phenotype of the typical form of a species as it occurs in nature. Originally, the wild type was conceptualized as a product of the standard "normal" allele at a locus, in contrast to that produced by a non-standard, "m ...

pigmentation for many

domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...

mammals Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

. It is a highly recognized characteristic trait of several animals, including many wild

canids Canidae (; from Latin, ''canis'', "dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid (). There are three subfamilies found within th ...

, wild

felids Felidae () is the family of mammals in the order Carnivora colloquially referred to as cats, and constitutes a clade. A member of this family is also called a felid (). The term "cat" refers both to felids in general and specifically to the dom ...

, wild

rabbits Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit specie ...

, and wild

rodents Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are nat ...

such as the namesake

agouti The agouti (, ) or common agouti is any of several rodent species of the genus ''Dasyprocta''. They are native to Middle America, northern and central South America, and the southern Lesser Antilles. Some species have also been introduced else ...

Canines

dogs The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

there are four alleles on the agouti locus with the hierarchy of dominance (

epistasis Epistasis is a phenomenon in genetics in which the effect of a gene mutation is dependent on the presence or absence of mutations in one or more other genes, respectively termed modifier genes. In other words, the effect of the mutation is dep ...

): Ay, aw, at, a. This means a descendant can only develop a recessive coat pattern in the

phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...

if both parents are genetic carriers of the corresponding allele or if one parent inherits an epistatically underlying allele to the offspring. The alleles Ay, at and a are not present in wild wolves that have no domestic dog among their ancestors.Sheila M. Schmutz:
Agouti Sequence Polymorphisms in Coyotes, Wolves and Dogs Suggest Hybridization
' File:Canis_lupus_signatus_-_01.jpg, An Iberian wolf with agouti coloration File:Bucuresti, Romania, acelasi dulau, frumos de Cotroceni.JPG, An agouti dog File:AustrKelpieBlackTan1 wb.jpg,

Australian Kelpie The Australian Kelpie, or simply Kelpie, is an Australian sheepdog capable of mustering and droving with little or no guidance. It is a medium-sized dog and comes in a variety of colours. The Kelpie has been exported throughout the world and is ...

Genotype at
black and tan File:Oola - 6 months.jpg, Great Dane Genotyp Ay either homozygous or in combination with one of the other alleles File:Agouti Locus inheritance pattern F1.png, cross of two different homozygous individuals File:Agouti Locus inheritance pattern F2.png, cross of two
genetic carriers File:Agouti locus inheritance pattern 3 cross with genetic carrier.png, Cross of a homozygous individual with a carrier

References

Animal coat colors {{Vertebrate anatomy-stub

Canines

See also

References