Researchers discovered that the vivid red murals in the Zuojiang River valley, China, created around 2,000 years ago, may have withstood successive monsoons through the use of human blood. Chemical analyses identified human proteins in a binding agent beneath the red pigment of Huashan, which would have helped fuse the pigment to the rock.
The authors of the new study suggest that this use of human blood may be linked to childbirth or fertility rituals, although they acknowledge this is a hypothesis and not a confirmed fact.
For decades, researchers have wondered how this rock art managed to remain practically intact for so long, exposed to the region's harsh climatic conditions.
The discovery represents an important clue for understanding the techniques used in creating this ancient art and the possible cultural practices or rituals associated with the paintings.
