* The tradition is more about folklore than science: Groundhog Day is a fun, centuries-old tradition rooted in Pennsylvania Dutch folklore. The idea that a groundhog's shadow predicts the length of winter is a charming myth, not based on scientific observation.
* Groundhogs are primarily focused on survival: They're more concerned with finding food, avoiding predators, and preparing for the upcoming season. While they might notice changes in light, it's unlikely they have a human-like understanding of shadows and their supposed significance.
* The "prediction" is determined by humans: The people watching the groundhog determine if it sees its shadow. This is based on the groundhog's behavior, which is influenced by many factors besides light, such as weather and its individual personality.
So, while a groundhog might perceive changes in light, it's unlikely they're consciously "seeing" their shadow in the way humans understand the concept. Groundhog Day is more about celebrating the changing seasons and enjoying a bit of playful tradition.