How Cats, Rats, Bats, and More Became Halloween Animals

No Halloween haunted house is complete without a black cat lurking in the window, and spiderwebs stretched across dark corners. Perhaps a menacing bat, hanging from the ceiling, greets those who dare to pass through the front door.

Certain animals are simply synonymous with Halloween. But why? For starters, says Stanford University classics scholar Adrienne Mayor, they're "nocturnal and predatory."

"They engage in mysterious activities in the dark and so they have been cloaked in superstition since ancient times. The combination of dark gray, brown, or black shades with cryptic nighttime habits evoked a sense of awe and fear back in the time when the only lights at night were oil lamps and wax candles."

In honor of America's spookiest holiday, we asked Mayor to tell us more about the shadowy nature of Halloween's creepiest creatures.