Agouti is a type of
fur coloration in which each
hair displays two or more bands of
pigmentation. 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 ...
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 use ...
, 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 ...
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 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 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), fu ...
. It is a highly recognized characteristic trait of several animals, including many wild
canids
Canidae (; from Latin, ''canis'', "dog") is a family (biology), 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 subfamily, ...
, wild
felids, 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 spe ...
, and wild
rodents 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
In
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 relativ ...
there are four alleles on the agouti locus with the hierarchy of dominance (
epistasis): 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 prop ...
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 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
See also
*
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 ...
, an animal of order
Rodentia
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 n ...
it was named after
*
Agouti gene, an important gene in the determination of coat color
References
Animal coat colors
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