Do the symptoms of seasonal affective disorder resemble the behavior of animals in the fall and winter?

Hibernation. With limited exposure to a certain waveband of light, it is believed that more melatonin is produced in the brain. This is the same chemical that induces hibernation in certain mammels.
Yes. I think of it like a hibernating bear that eats a lot food & gains weight in preparation for a long winter nap. People can have low energy level, sleep more, have increased appetite, gain weight, be amotivated and feel sluggish.