Legend has it that, if a groundhog sees their shadow on February 2nd, six more weeks of winter will follow, otherwise, an early spring will come.

Groundhog Day is a reimagining of Candlemas Day, according to Chicago Tribune. The event is a Catholic midwinter festival rooted in pagan celebrations. Accordingly, Europeans observing Candlemas would track hedgehogs to predict when winter is going to end.

American woodchucks, also known as groundhogs from the marmot family, seem to fit the European hedgehogs and since then referred to by European migrants to predict the changing of the season. Predictably, males of the species would pop out of their burrows each February, almost on the exact date, year after year. According to The Daily Mail, the average date that a groundhog emerges from its burrows is February 4.

Apparently, the furry rodents have nothing to do in predicting the changing of the seasons. According to research studies into groundhog biology, the animals have other priorities in early February in Punxsutawney, Pennsylvania. Groundhog Day came to eastern Pennsylvania by way of German immigrants.

The seasonal crossroads have always been celebrated throughout history. In this period, the winter solstice and the spring equinox happen during this time in early February. Greeks and Romans celebrate theirs during February 5th; the Celts have celebrated it as the festival of Imbolog.

Early European Christians embraced the tradition and celebrated Candlemas Day every February 2nd, commemorating the purification of the Blessed Virgin Mary. Whatever the reason, all celebrations has ties to the anticipation of spring.

Groundhog Day's real purpose

The real reason for the groundhogs yearly emergence from their burrows lies mainly on, sex. Their real objective is related to Darwinian fitness to be able to contribute genes to the next generation.

The marmot's hibernation cycle adds to the animal's Darwinian fitness value. The process of hibernation enhances the groundhog's survival rate by conserving energy during the lean months where there is a limited source of food.

However, why do the groundhogs emerge in February, when they will not mate until March? The answer lies in the animal's social structure. They are solitary, territorial, and generally antagonistic towards each other. February is the time used by the animals to re-establish male and female bonds necessary for them to mate in March.

To put it in simple terms, Groundhog Day to them is the equivalent of our Valentine's Day.