Hibernation

Ever notice how you get tired and sleepy more during the winter months? As the days become shorter, the desire to sleep is hard to ignore. I do wonder if people are designed to sleep more in the winter months just like bears? Many of us are drawn to starchy, carbohydrates in the fall. I wonder if we are being driven to fatten ourselves up for a long winter's nap? Or is the lack of a nap driving us to seek sugars?