Experts say a spectrum of natural sleeping and waking rhythms exists, ranging from extreme morning people to extreme "night ...

“When an animal is active and when it needs access to certain resources could be critical for protecting a species.” [ Related: Mountain lions in Los Angeles become night owls to avoid humans.

Creatures that sleep during the day and are active at night are known as nocturnal ... Here are ten of the most fascinating ...

the Owl quickly established itself as the animal embodiment of the power of clairvoyance. Clairvoyance of that which eludes man, clairvoyance beyond the darkness, beyond even the veil of night ...