Some Maya rulers may have been incinerated and their ashes mixed with rubber to make the balls used in the game of pelota, an archaeologist says. Burnt human remains uncovered at the ruins of a Maya city have led to a new theory about the death rites of the ancient civilization. Archaeologist Juan Yadeun Angulo came up with the hypothesis after finding urns containing human ashes, rubber and roots at a Maya temple in Mexico. Pelota is among the oldest team sports. Mr. Yadeun, an archaeologist with Mexico’s National Institute of Anthropology and History (INAH), has been studying a recently uncovered crypt underneath the Sun Temple at the Toniná archaeological site in southern Mexico. Inside the underground crypt and its antechamber, archaeologists found 400 urns containing the mixture of human ashes, coal, rubber and plant roots.