A shadow creeps across the face of the full moon at midnight as a chill wind blows across a desolate landscape of dead trees with claw-like branches and jagged, fang-like rocks. You shiver involuntarily. Then an eerie sound begins, a howl that rises and falls, sending a line of cold rippling down your back. More voices join in the howl, and the sound comes closer and closer.

Or picture the full moon in a winter’s sky, a huge silver orb. In the foreground, on the top of a bare, rocky cliff, a pack of wolves sits, muzzles turned to the sky as they howl, a spine-tingling chorus of notes that rises and falls. The howl continues, echoing off the untouched snow and the bare rocks.

These wolf-howl scenes could be from an adventure story, a fantasy or horror tale about werewolves or even the introduction to a non-fiction work about the life and habits of wolves. A howl is a primal, animal sound that has the power to conjure up a range of emotions in human beings, ranging from delight and awe to horror and fear.

But for wolves, the howl is a different matter. Wolves howl as a form of communication and, according to some observers, to build solidarity and bonding within a pack. Naturalists have often observed that if one wolf in a pack starts to howl, they all start to howl along with it.

Dogs, especially some breeds, have this howl instinct still inside them. You’ve probably heard a dog that likes to howl along with any loud, resonant, rhythmic sound that for some reason reminds the deep-down wolf inside them of a howl. I have even heard a dog deciding to howl along with church bells. And if you have a dog that likes to howl, then singing to the dog and making it howl back at you can be an amusing party trick.

Some dogs howl more than others. The dog owned by this writer doesn’t howl at all, even when we try to get a response by trying to howl ourselves. Our neighbour’s dog, however, will howl all the time. In particular, this dog will howl if it hears an emergency vehicle siren. And as we live on a busy main road, we hear it howl quite a lot (I’ve heard this dog howl so many times, our family refers to it as “Siren”).

But the genuine wolf-howl isn’t so amusing (or annoying) as a dog’s howl. A real howl heard in lonely woods heard under the moon (full, gibbous or crescent) is something that guarantees to stir the emotions. A howl is a sound that reaches in to a primal, instinctive part of our bodies and triggers a reaction.

It is these emotional reactions to a howl, combined with the mythical and legendary associations of the wolf – both good and evil – that leads to a howl being used as a sound effect for suspense in a chilling movie, whether as an atmospheric effect to suggest loneliness or isolation, or for a more sinister effect in a werewolf story.