Polar Bears
Although still primarily a terrestrial animal, the polar bear shows the beginnings of aquatic adaptation to swimming (high levels of body fat and nostrils that are able to close), diving, and thermoregulation. Distinctly polar bear fossils can be dated to about 100,000 years ago. The polar bear has thick fur and layers of fat on its body to protect it from the cold.
Read more about this topic: Aquatic Adaptation
Famous quotes containing the words polar and/or bears:
“In time your relatives will come to accept the idea that a career is as important to you as your family. Of course, in time the polar ice cap will melt.”
—Barbara Dale (b. 1940)
“When icicles hang by the wall,
And Dick the shepherd blows his nail,
And Tom bears logs into the hall,
And milk comes frozen home in pail;
When blood is nipped, and ways be foul,
Then nightly sings the staring owl:
Tu-whit, tu-whoo!—
A merry note,
While greasy Joan doth keel the pot.”
—William Shakespeare (1564–1616)