According to a recent article published in the journal Scientific Reports, hair strands from the Bronze Age of Europe provided the first concrete evidence of drug use stretching back 3,000 years.

The hair contains psychoactive alkaloids, which can cause altered states of consciousness and are naturally present in some plants. Archaeologists speculate that prehistoric people may have consumed them during ceremonial rituals.

The hair was found in a cave on the Spanish island of Menorca, which is located in the Mediterranean Sea off the coast of mainland Spain. According to the experts, humans originally lived in the cave known as Es Càrritx some 3,600 years ago.

In 1995, spelunkers discovered Es Càrritx. When archaeologists began excavating the site, they found the bones of about 210 people as well as sealed, ornamental vessels filled with red-dyed hair strands.

The hairs were thoroughly examined by scientists using ultra-high-performance liquid chromatography and high-resolution mass spectroscopy. Two alkaloid chemicals that can lead to hallucinations, delirium, and altered sensory perceptions were discovered: atropine and scopolamine. Ephedrine, a stimulant that can heighten alertness and excitement, was also found by them.

Some plants, such as mandrake, henbane, horn apple, and joint pine, were probably eaten by our Bronze Age ancestors to get those components. Scientists came to the conclusion that these people had been taking the medications for at least a year.

The research speculates that shamans may have utilized the chemicals while conducting religious rituals, but it is unclear why these populations were taking them. The pots that held the hair were painted with concentric circles, which the experts suggest could have symbolized the “inner vision” received by swallowing the plants.

As independent ethnobotanist Giorgio Samorini tells Andrew Jacobs of the New York Times, "This was not a profane purpose of'searching for a high,' but rather the search for existential meaning that has been largely lost to time."

Drugs that change consciousness are "usually invisible in the archaeological record," according to the researchers, but their usage "used to be inferred from indirect evidence," such residue on pottery. However, the hairs offer the first concrete evidence of drug use among Europeans.

There aren't many hairs left from this time and place. We are very, very lucky, says study co-author Elisa Guerra Doce, a prehistorian at the University of Valladolid, to Tom Metcalfe of National Geographic.