Well next season's series of Ancient Aliens is writing itself...
Close to the small Mexican village of Onavas, south Sonora, archaeologists have uncovered the first pre-Hispanic cemetery of that area, dating to around 1,000 years ago.
The burial ground consists of 25 individuals; 13 have intentional cranial deformation and five also have dental mutilation, cultural practices which are similar to those of pre-Hispanic groups in southern Sinaloa and northern Nayarit, but until now, have not been seen in Sonora.
...For archaeologists, the discovery is exciting new evidence of cranial deformation, something which has not been recorded before in the Sonora cultural groups.
...The archaeologist said that, “Cranial deformation in Mesoamerican cultures was used to differentiate one social group from another and for ritual purposes, while the dental mutilation in cultures such as the Nayarit was seen as a rite of passage into adolescence. This is confirmed by the findings at the Sonora cemetery where the five bodies with dental mutilation are all over 12 years in age.”
However, she continued,“In this case, you cannot recognise any social differences because all the burials seem to have the same characteristics. Nor have we been able to determine why some were wearing ornaments and others not, or why of the 25 skeletons only one was female. “
Video report about the discovery below (Spanish language). Maybe our resident Mexico expert RPJ can fill us in a little more about this fascinating cultural practice: