According to legend, if the groundhog sees his shadow on February 2nd, there will be six more weeks of winter; if not, an early spring is predicted.
Of course groundhogs – also known as woodchucks – don’t emerge at this time just to be furry weather predictors. So what’s the real reason?
Research into groundhog biology shows they have other priorities in early February than mingling with the people of Punxsutawney, Pennsylvania.
Groundhog Day appears to have European roots. Early February is midway between the winter solstice and the spring equinox, and throughout history this seasonal crossroads has been celebrated.
According to legend, if the groundhog sees his shadow on February 2nd, there will be six more weeks of winter; if not, an early spring is predicted. File photo
The ancient Greeks and Romans observed a mid-season festival on February 5th in anticipation of spring.
In the Celtic tradition, this period was celebrated as the festival of Imbolog to mark the beginning of spring.
Early Christians in Europe embraced this tradition and celebrated Candlemas Day on February 2nd, to commemorate the purification of the Virgin Mary.
Customarily on this day, clergy would bless candles and distribute them to the people in the dark of winter in anticipation of spring.
In northern Europe, farmers needed some indication when to start spring planting. They looked for the emergence of hibernators, such as the hedgehog or badger, to signal the coming of spring.
Since their emergence occurred in early February, it was believed that if Candlemas Day was sunny, and the hibernator saw its shadow, more wintry weather was ahead.
But if it rained or snowed on Candlemas Day, the rest of the winter would be mild.
This tradition was brought to America by the Germans who migrated to eastern Pennsylvania.
They found groundhogs in profusion in many parts of the state and decided this mammal was a perfect replacement for the hibernators they’d left behind in Europe. Thus, the tradition continued in America.Hibernation helps survival
In my study area in southeastern Pennsylvania, the average date groundhogs emerge from their burrows is February 4. This fits the folklore and the timing of Groundhog Day. However, predicting the weather is not their objective.
The real reason is related to Darwinian fitness – a measure of an organism’s ability to contribute its genes to the next generation.
The process defines natural selection and is based on an organism’s ability to survive and to reproduce successfully. High Darwinian fitness suggests an individual will pass on its genes to many healthy offspring.
Hibernation contributes to Darwinian fitness value. It enhances survival by saving energy during times of limited food availability.
Hibernation is characterized by a significant drop in body temperature and metabolic function. This process is commonly called torpor. Above, a female groundhog can be seen emerging from her burrow in late January