“Death whistles,” or Aztec skull whistles, were short, carved instruments made of two opposing chambers where air could clash and create a “ screeching sound ,” according to a Nov. 19 news release from researchers at the University of Zurich in Germany.

The mysterious Aztec "death whistles" have fascinated researchers with their eerie, terrifying effect they have on the listener.

Archaeologists unearthed the first Aztec death whistles, also known as ehecachichtlis, in 1999 while excavating the Tlatelolco site in Mexico City. They found the body of a sacrificial victim, a 20-year-old male who had been beheaded,

The Aztec death whistle is a mesoamerican instrument designed to imitate a human scream, and was often used during battle or at sacrificial ceremonies. Researchers from the University of Zurich analyzed the whistle and studied its psychoacoustic effect on listeners.

Brain scans of modern listeners suggest that Aztec whistles sound like human screams, which may have prepared sacrifice victims for their journey to the underworld.

A team of scientists from the University of Zurich, Switzerland, has created 3D reconstructions of several Aztec skull whistles from the Ethnological Museum in Berlin, Germany. In research published on November 19,

Whistles shaped like skulls were used to create the sound of screams by the Aztecs. Elevate your camping experience with essential outdoor cooking skills! Watch a million colorful matchsticks come together to create an explosive volcano that’s both visually stunning and soothing.