If your child is afraid of the dark, give the child a nightlight. That child knows what he or she is doing, although perhaps not consciously. We all are afraid of the dark, though as we grow up most of us overcome it. But we can notice a residue of fear when we come home on a dark night. The first thing we do is turn on the lights. It’s worth noticing the slight sense of relief we feel when the light goes on and we see what’s around us.
For this we can thank our ancestors.
We inherited our fear from them because it helped us to survive. And this, says ecologist Craig Packer, was probably because of lions. In a fascinating paper, “Fear of Darkness, the Full Moon and the Nocturnal Ecology of African Lions,” Packer and his coauthors discuss fatal attacks on people by lions, which most often take place during the first few hours of the nights that follow the full moon.
Today we don’t pay much attention to the moon, and not everyone knows that the full moon rises at sunset and on the following nights it rises later, getting smaller, until the last three days of the moon’s cycle, when it rises with the dawn. We don’t see its little crescent until late afternoon. After that, until it’s full, it’s in the sky before the sun sets, so it’s already there when it gets dark and for most of the night we have moonlight. On those nights, our ancestors had less to worry about. It was after the full moon that they were in danger.
People of industrial societies no longer cope with lions, but people in African villages do. In one of the languages spoken by the Kalahari Bushmen — the first people, also the last to live as hunter-gatherers — a metaphor for “lion” is “moonless night.” At least two such societies hold their important healing dances or trance dances in relationship to lions — the Bushmen dancing on nights of the full moon and the Hadza on the nights of absolute darkness. During the dance, the Bushmen trance-dancers run out in the dark away from the dance fire and curse the lions, telling them to go. According to Chris Knight, a researcher who studied the Hadza, the dancers refer to the songs of the dance as scaring away predators. They say “we are singing for our lives.”
When all of us lived as hunter-gatherers, the lions knew about our encampments and had no reason to fear us. Our weapons were spears with stone points — not much use against a lion — or perhaps poison arrows, which take days to kill a victim, or fire, which the savannah animals would have known as well as we did. A raging brush fire started by lightning might seem scary to a lion, but a campfire would not.
If a lion came near our encampments, the firelight might show his shining eyes, and we could pull a burning branch out of the fire and shake it at him — that’s what the Bushmen did — but many lions seem to know that their eyes shine, and can approach without being noticed, especially if it’s very dark. If we tried to run away they’d catch us. The world’s fastest person once ran at 27 miles an hour but almost any lion can run at 50 miles an hour for a short distance, and that’s all he needs. We would have been easy prey.
So we would see the full moon with mixed emotions — it would light up the world on that one night, but its presence would signal that dark nights were coming. Thus our fear of the dark had survival value. It kept us in our encampments with our children nearby. Even today many children are scared to be alone in the dark. They have little to fear today, but back then the fear was essential.
It’s interesting to think of all this when we come home on a dark night. We turn on the lights and we see what’s around us. Good! No lions.
Elizabeth Marshall Thomas is a naturalist and the author of many books, including the bestseller “The Hidden Life of Dogs.” In two weeks this column will be devoted to answering readers’ questions about animals. Submit yours to syandlizletters@