In the dusty ruins of Vichama, an ancient city where one of America’s oldest civilization once lived, archaeologists have unearthed a 3,800-year-old engraved wall that illustrates swirling snakes, worried human faces, and a chirpy-looking "anthropomorphized seed head", but it may have a darker story.

The incredible discovery was recently dusted off at the Caral Archaeological Zone (ZAC), the site of a former fishing town of the lost Caral civilization situated in Huaura province in modern-day Peru.

The site contains around 22 structures and was once the location of the city of Vichama some 3,800 to 3,500 years ago. The people who lived here belonged to the Caral civilization, also known as Norte Chico, which is considered to be the earliest known civilization in the Americas.

Don’t be fooled by this mural’s cartoonish faces, this scene was created to illustrate a much deeper message. Founder and director of the ZAC archaeological project, Dr Ruth Shady believes that the relief symbolizes the fertilization of Earth, and could be related to people experiencing the effects of climate change back then.

The snakes likely represent a deity who was linked to water and the rains, while the happy seed character depicts germination and the renewal of plant life. The human faces, perhaps, represent people desperately hoping for rain.

“Previously, in another building of the same old city, other sculptural reliefs were recovered, linked to the period of scarcity and famine,” ZAC explained in a statement. “The new relief reinforces the approach of capturing the collective memory and the difficulties faced by the society due to climate change and water scarcity, which caused serious effects on agricultural productivity."

The wall once faced a public sunken circular plaza facing towards the cultivation fields of the Huaura Valley, where the Caral would have certainly hoped rain would fall.

The Caral was a civilization that took root in north-central coastal Peru between the fourth and second millennia BCE. The jewel in the crown of this civilization is The Sacred City of Caral-Supe, a 626-hectare area that’s listed as a UNESCO World Heritage Site. In the words of UNESCO, the site is “the best representation of Late Archaic architecture and town planning in ancient Peruvian civilization" and the "the earliest known manifestation of civilization in the Americas."

Little is known about what happened to the Caral, so they’re often called a “lost civilization”. However, if this mural is anything to go by, the unforgiving environment could have played a crucial role in their demise, just like the Mayans some 2,600 years later.