Squirrels

1. That Big Bushy Tail has a Bunch of Uses

It functions as a built-in blanket in the winter and as a sunshade in the summer. The tail also helps them balance and can be used for communication.One researcher taught some squirrels on a college campus to open boxes that could contain either a walnut, a kernel of dried corn or nothing. Sometimes the boxes were locked. She videotaped the results and found that the squirrels used a long, sweeping tail movement (as opposed to the usual twitching) when they found a box with no goodies or that was locked. She isn't sure if that tail movement was an expression of disgust or a warning to other squirrels not to waste their time. Squirrels use that same tail movement when they get into fighting mode.

2. They Practice "Deceptive Caching"

Squirrels, of course, are famous for hiding nuts as a food supply for the winter. But they also have to protect their precious cargo from other squirrels or birds (25 percent of their hoard is lost that way). So how do they do this? A biology professor at Wilkes University in Pennsylvania found that sometimes squirrels engage in deceptive caching. A squirrel will dig a hole and cover it up, all the while holding a nut in its teeth and not depositing it. The squirrel sometimes repeats this behaviour several times. Another researcher found that when she and her students uncovered these holes, the squirrels dug subsequent holes in locations that were harder to get to. By the way, squirrels don't uncover all the nuts they've buried in holes — many of those acorns and other nuts may grow into trees. Thanks, squirrels!

3. They're Also an Invasive Species

In England, the grey squirrel muscled in on the native red squirrel's territory, contributing to its rapid decline. Scientists also found the grey squirrel carries a virus that is deadly to the red squirrel (pictured below). In the U.S. (and elsewhere), squirrels are known to peel bark off trees in search of sap, or to make homes in attics if there's a hole in a roof through which they can enter. Once inside, they may gnaw through home wiring and insulation. While some people might view them as pests, we share some of the blame for this reputation. Squirrels thrive wherever there's an abundant food supply. And they don't just eat nuts — they'll eat birds, insects, even cheeseburgers or chocolate-chip cookies if they're handy. If you keep your home sealed (filling in cracks in the doorways and chimney), keep tree limbs cut back from the roofline and don't leave garbage lying around, they are less likely to come inside.