Guest post by John L. Koprowski For many, the days of winter may seem endless. Perhaps the shininess of the New Year has begun to dull. But there is reason to celebrate! The "High Holy Days of Biology" are upon us. To the student and professional or lay biologist, the excitement of this festive season continues! I share with my students at the University of Arizona each year the "biologically important" days of winter. Squirrel Appreciation Day." And just who cannot appreciate a squirrel? For some, we may marvel at their ability to raid the birdfeeder and utter the occasional curse word not quite loud enough for our neighbor to hear. But look again as that squirrel descends a tree and notice how it rotates its ankle 180 degrees from the normal forward position and tell me that that flexibility alone does not deserve a day of appreciation. And so, for the eastern gray squirrels and fox squirrels that have scatterhoarded the fall bounty of nuts or the red squirrel that has piled the winter’s supply of pine cones into a larder, we will raise a spoonful of peanut butter (although I prefer Nutella for a chocolate fix) in recognition. February 2nd arouses from hibernation the talented and revered rodent prognosticators to apply their skills on Groundhog Day. The morning news shows will provide coast-to-coast coverage of this most important event. Complete the day with a warm beverage, the internal calm that comes with the knowledge of when winter will end, and the classic Bill Murray movie of the same name. Finally (and yes, you WILL likely already be exhausted from the previous two celebrations), get the birthday cake in the oven to celebrate on February 12th the birthday of Charles Darwin and his formulation of evolution by natural selection! On the very same day in the very same year (1809) across the Atlantic Ocean in a one-room log cabin on a Kentucky farm, a baby boy, Abraham Lincoln, was born. A pretty good day in history! For me, I also get to delight in the birth of a third incredibly influential person, my mother, Judith Koprowski (although I am certain that she would want me to note that the birth year was not the same as for the other two guys! In fact, the year will go unmentioned!). Please continue to rejoice and celebrate the “High Holy Days of Biology” this winter . . . there is much to appreciate! John L. Koprowski is a professor of Natural Resources and the Environment at the University of Arizona. He teaches courses in ecology and conservation and researches these topics on a variety of wildlife species at various levels of conservation threat. He is the coauthor of three books on squirrels, including Squirrels of the World forthcoming this fall from the Johns Hopkins University Press.