Since that time, off the big screen and out in the real world, hundreds of thousands of other wild things have found themselves transplanted into the homes of Americans, catching rides on hundreds of thousands of versions of "the Griswold family Christmas tree."

Insects are the most frequent Christmas tree-transported visitors to our holiday households, and the egg cases of praying mantises seem to be the most frequently reported. The female mantids cement their Styrofoam-resembling, tan to gray-brown egg cases to plant stems and twigs, including the branches of Christmas trees, in early fall.

Not nearly as often discussed are the two most common tree hitchhikers: aphids and spiders.

Again, it's all about the eggs that the adult insects and arachnids laid on the stems of a tree in late summer or fall. If the tree had remained outdoors, the eggs would have remained dormant throughout through the winter to hatch next spring. But, they've been brought indoors for the holiday.

Many holiday celebrants never realize the critters have entered their homes. The tiny insects and spiderlings -- most about 1/16th of an inch in size -- survive only a short time before dying of desiccation or starvation and move only a short distance from the spot where their mother laid the eggs.

Even the few that might make their way farther into the world pose no threat to the humans or pets in the home. They can't bite or string, and they're still destined to die very soon.

Bark beetles, mites and scale insects are the other primary groups that might cling to Christmas trees, but they all will generally meet the same fate when brought into the home....