Question
I always ask myself what is better. Leaving some lights on wouldn't prevent the dog to have a nice sleep? Leaving all lights off woudn't make her to be affraid and scared?
Answer
It depends on the individual animal, of course, but the wolf ancestors of domesticated dogs are nocturnal, and dogs have good low-light vision. Most dogs are not afraid of darkness.
For roughly the same evolutionary reasons, most dogs won't be kept awake by light; they've been domesticated to follow a roughly diurnal schedule but their wolf ancestors slept mostly during the day. And indeed many dogs seem to prefer to sleep in patches of sunlight (although it's likely the warmth rather than the light itself they're seeking...)
Answered By - Wooble