Penguins :: essays research papers

Myopic little men in tuxedos, or highly efficient land/water animals? Recent research indicates there's more to penguins than meets the eye. If you've every wondered what it would be like to be able to see as clearly under water as you can on land, just ask the nearest penguin.Most aquatic animals are short-sighted on land. Most terrestrial animals (and that includes us) are far-sighted under water. But researchers have discovered that penguins can apparently see equally well in both environments, because of the unique structure of their eyes. Penguins have to be able to see well under water because their diet consists mainly of plankton, molluscs, crustaceans, and the inevitable fish. Through a special slowing-down of their heart rate they're able, like many other diving animals, to stay submerged long enough to search out and chase whatever catches their fancy. On dry land, it's a different story-or has been up to now. Waddling along on their flat little feet, eyes fixed intently on the ground, penguins appear myopic, inefficient and generally out of place. In fact the reverse is true. During a recent stay on the Falkland Islands, a Canadian researcher discovered that penguins are able to recognize individuals and navigate the rocky terrain on which they live quite well. Long of body and short of leg, they probably poke their heads forward as an aid to balance. And as for looking at the ground, they're merely-like us-keeping an eye on where they're going. The human eye is adapted for aerial vision, which is why scuba divers-or even you and I in the local swimming pool-must wear goggles or a face mask to re-introduce air in front of our eyes in order to see clearly. Among vertebrates in general, the bird eye is frequently described as the most efficient. Its superior quality, combined with the fact that a large number of birds-cormorants, pelicans, seagulls, even ducks, as well as penguins-get their food from water, obviously