And now for something completely different! If you’re like me and facing impending wintry doom here in the Northeast, you could probably use a break. If you’re somewhere else in the world, here’s a highly random diversion for you anyway.

January 21st is National Squirrel Appreciation Day.

Eastern gray squirrel. Credit: waferboard (Wikipedia).

Squirrels are the only mammals that can climb down trees headfirst. This is because they can turn their feet around backwards.

Black squirrel (actually an eastern gray squirrel). Credit: D. Gordon and E. Robertson.

In some parts of the country, including here in Princeton, you can see black squirrels. These are actually a subtype of the common eastern gray squirrel.

Fox squirrel. Credit: Davefoc (Wikipedia).

In the eastern half of the United States, gray squirrels coexist with fox squirrels, which may be distinguished by their larger size and brown undersides.

Squirrels are surprisingly intelligent and tenacious. Here is a fox squirrel successfully infiltrating a “squirrel-proof” bird feeder.

It would appear that “squirrel-proof” is a relative term.