The appearance of the dark eumelanin pigment is altered so that the penguins appear brown and white rather than black and white. Brown penguinsĪ relatively common aberration is simply known as ‘brown’. The degree of leucism can range from just a few feathers to the entire plumage. Unlike in albinistic birds, not every pigment-producing cell is necessarily affected - meaning that penguins can be partially leucistic. The mutation causing leucism enables the production of the pigments in the epidermis, but the mechanism to deposit the melanins into the feathers is faulty. There are also completely white penguins whose beaks and eyes are pigmented (not pink). They usually do not live very long because they tend to become blind and can no longer fend for themselves. Albinism is a serious condition for penguins. An albinistic penguin (or an albino) also lacks any pigments in its beak, skin and eyes, making these parts appear pink. Melanistic and albinistic (albino) penguinsĬolour aberrations range from ‘melanistic’ (a penguin whose normally white parts are black) to ‘albinistic’ (a penguin that lacks both melanins and is totally white). It is often difficult to determine the type of mutation that has taken place just by looking at a penguin. At times, the plumage colouration of individuals is very different from the norm. The dark colouration of penguin feathers is due to two pigments, called phaeomelanin and eumelanin, which are collectively known as melanins. The yellow pigments are unique to penguins. Only some penguin species sport yellow feathers on their heads and chests, but all have a basically black and white body. Once the penguins have undergone their annual moult, their plumage is soft and shiny, and the brand new feathers are deep grey or black. All feathers need to be replaced every year having been worn out by the sun, sea salt and other environmental factors. Plumage colouration can be a visual signal identifying a bird’s species, sex, age and even health.īefore penguins moult their plumage looks dull and almost brown. Penguins may not have a wide range of colours, but plumage colour is still important. However, the nature of others can really only be determined properly through genetic analyses. Some of those can be identified by just looking at a bird. Unusual plumage colourations (or colour aberrations) can be caused by a variety of factors including injury, diet and disease, but many are due to mutations (alterations in genetic material). Both hybrid penguins and penguins with non-standard plumage are relatively rare. Various types of unusual penguins call Antarctica and the sub-Antarctic home, including penguins with different plumage colourations and hybrid penguins (offspring of cross species mating).
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