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Penguins
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They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages.
The Auk of the Northern Hemisphere is superficially similar to penguins. They are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution.
• Isabelline penguins
Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband's siege of Ostend was successful—which took over three years to accomplish. Isabellinism is different from albinism. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well-camouflaged against the deep, and are often passed over as mates.
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