Penguins have a special gland in their beak that filters salt from their blood and enables them to drink sea water.
Penguins at Sea World © Sophia Volzke
Those animals that live in the frozen environment of Antarctica have to be highly adapted to survive. The penguin is one of these true wonders of evolution.
As a species of bird their wings function as flippers, sacrificing the ability to fly for better coordination while hunting for fish under water.
Their famous black and white tuxedo outfit is also not just a cute feature look, but allows the animal to camouflage underwater. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface, while the dark plumage on their backs protects them from being spotted from above.
Another special adaption is the ability to drink salt water. The penguin’s surrounding environment does not offer much fresh water because it is frozen into ice. Furthermore these animals automatically swallow a lot of sea water while propelling themselves through the ocean using their strong beaks to catch prey. Therefore the so called Supraorbital Gland in the beak of these birds is a brilliant and logic invention of nature. Blood travels through the gland, which filters the salt before it travels through the penguin’s body. It then mixes with a small amount of moisture inside the gland and travels down the nasal passages. These salt-laden drops drip out the penguin’s nose.
Penguins often shake their heads to release the drops and get salt off their beaks.
The supraorbital gland serves only this one purpose in all penguin species. But these animals do not have an excessive need for salt compared to other animals. They have no trouble drinking fresh water if it is available. Some even eat snow as a source of water. Penguins in zoos live in fresh water, and some species, such as rockhopper penguins, prefer to live around fresh water instead of saltwater.