Xanthism (from the Greek. Ξανθός - yellow) - a violation of the pigmentation of the external integument (skin, wool, feathers, scales, eggshells) in any animal species in favor of yellow or orange.
Xanthism can occur both because of an excess of yellow pigment in the coloring of the outer integument of animals, and due to the lack of melanin , then the remaining carotene and other pigments give the animal a characteristic color, this is a form of albinism . [1] The second case is impossible for mammals , since their carotenoids and pteridins do not play any role in the formation of color, and is peculiar to fish, amphibians, reptiles and birds. [2] [3] [4] .
Excessive yellow color is usually caused by genetic causes, but can also be caused by external, for example, some substances.
Xanthism is much less common than albinism .
The opposite of xanthism, deficiency or complete absence of yellow pigment, is called axantism.
Xanthism Examples
- Animals with xanthism and individuals without pigment abnormalities
Red-eared turtle
Goldfish
Decorated Slingshot
Pink-cheeked lovebird
American lobster
See also
- Albinism
- Erythrism
- Melanism
Notes
- ↑ Bruce J. Turner and Robert K. Liu: Xanthic Variants in a Natural Population of the Salt Creek Pupfish, Cyprinodon salinus. The Southwestern Naturalist, Vol. 22, No. 4 (Oct. 15, 1977), pp. 538-540
- ↑ J Odenthal, K Rossnagel, P Haffter, RN Kelsh, E Vogelsang, M Brand, FJ van Eeden, M Furutani-Seiki, M Granato, M Hammerschmidt, CP Heisenberg, YJ Jiang, DA Kane, MC Mullins and C Nusslein-Volhard : Mutations affecting xanthophore pigmentation in the zebrafish, Danio rerio. Development, Vol 123, Issue 1 391—398, C 1996
- ↑ Frost-Mason SK, Mason KA: What insights into vertebrate pigmentation has the axolotl model system provided? Int J Dev Biol. 1996 Aug; 40 (4): 685-93. PMID 8877441
- ↑ Tony Gamble Archived April 30, 2009 on Wayback Machine , Jodi L. Aherns, and Virginia Card: Tyrosinase Activity in the Skin of Three Strains of Albino Gecko (Eublepharis macularius). Gekko 5: S.39-44. Archived January 27, 2012 to Wayback Machine (PDF; 767 kB)