Why does everybody get sad as the weather gets colder?

Why does everybody get sad as the weather gets colder?
Why does everybody get sad as the weather gets colder?

It’s not universal; I seem to hear as many complaints about the heat as I do about the cold, and fall weather perks a lot of you humans up. But if the cold (and possibly the dark, dark evenings since we put the clocks back) are making you sad enough that it is interfering with your life, you could talk with someone at University Counseling Services (bit.ly/BC-counseling).