“As the days grow shorter and cold, and darkness settles in, some begin to feel a little blue — hamsters and people alike.

Up to 20 percent of Americans report they feel more depressed during the winter months as a result of a condition known as seasonal affective disorder. Now scientists have shown that hamsters experience the same sluggishness when their exposure to light is reduced. By studying these sad hamsters, the researchers hope to find new ways of helping people combat seasonal depression.” (ABC News)