For hundreds of years, people have been looking up at the hazy peaks of the Santa Lucia Mountains in California at sunset and seeing tall, covered figures staring back. Then, in moments, the creepy silhouettes disappear.
These twilight appearances are known as the Dark Watchers – shady, sometimes 10 meter long (3 meter) men covered in ominous hats and caps. They appear mainly in the afternoon, and according to a recent article on SFGate.com, visitors to California have seen them sitting ominously on the mountain tops for over 300 years.
“When the Spaniards arrived in the 1700s, they started calling the appearance loose Vigilantes Oscuros (literally ‘the dark viewers’),” wrote Katie Dowd, editor-in-chief of SFGate, in the article. “And then Anglo-American settlers in the region, they also felt the need to be watched from the hills. “
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One well-known observer who felt the presence of the Watchers was the American writer John Steinbeck. In his short story “Flight” of 1938, a character sees a black figure leaning against him from a nearby ridge top, “but he quickly looks away because it was one of the dark viewers,” Steinbeck wrote. “No one knew who the viewers were and also not where they lived, but it was better to ignore them and never be interested in them.” (It was a family obsession; Steinbeck’s son, Thomas, co-wrote the book with the painter Benjamin Brode about the Watchers, Dowd writes.)
So, who – or what – are the Dark Watchers?
One theory, according to Dowd, is that they are merely figures of the observers’ pattern-seeking thoughts. In other words, this is a classic case of pareidolia: a psychological phenomenon in which the brain of an observer finds patterns or meaning in a vague or random image.
The phenomenon is why some people see Muppet faces on the moon, or the face of Jesus on toasted toast. In this case, ordinary shadows on the Santa Lucia hilltops can be interpreted by the viewer’s brain as long, enveloped figures (the Watchers tend to appear in the late afternoon, when long shadows still grace the hills).
This pattern-seeking effect can be amplified, according to Dowd, by the presence of fog or low-flying clouds. Shadows against clouds are responsible for another infamous illusion, known as the Brocken ghost.
“German residents near the Harz Mountains have seen for centuries that they see shadowy figures on Brocken Peak,” Dowd wrote. “In fact, the Brocken ghost happens … when shadows – like those of a hiker – are cast on misty mountain peaks. When the sun is behind the observer, the mist plays with the shadow and makes it look huge and threatening.”
The spectral figures are usually surrounded by a rainbow-colored halo, which is produced by sunlight that breaks down water droplets in the mist or clouds. according to the BBC. Although common in the Harz Mountains, where fog often creeps in at low altitudes, you can see the effect on any misty mountain slope with the sun on your back and the clouds below you. Maybe you saw it yourself at the window of a plane; sailing between the sun and the clouds, the plane can cast a shadow on the clouds below that look supernaturally large.
It is therefore possible that hikers in the Santa Lucia Mountains are simply staring into their own shadows while the Watchers watch. (Sorry, Steinbeck.)
Originally published on Live Science.