According to a story at Past Horizons Archaeology,
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…. Archaeologist Cristina Garcia Moreno, director of the research project…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.”
The main significance to archaeologists is that the discovery suggests the presence (or influence) of Mesoamerican societies much farther north than previously believed.
However for many UFO buffs, the discovery suggests something else entirely: that extraterrestrials (or their half-human hybrid offspring) may have been buried there. Of course the Internet being what it is, it didn’t take long for alien conspiracy theories to raise their oblong heads.
This is not the first time that weird skulls found in Mexico have been offered as evidence for ancient extraterrestrial visitation.
A child’s deformed skull — later dubbed the “Starchild skull”— was found in the early 1930s in the arid region around Chihuahua. It was later sold to a UFO researcher who has exhibited the artifact at UFO and paranormal-themed conferences for many years, claiming that it is too unusual to be fully human and is the offspring of an extraterrestrial male and a human female.
Scientists, however, are skeptical; two sets of DNA tests (one in 1999 and another in 2003) confirmed that the skull was in fact human: a Native American or Mesoamerican male child who likely suffered from hydrocephalus, a condition which leads to skull elongation and deformation.
A common theme pervades mystery-mongering circles: Anything not immediately explainable or obvious is interpreted as a baffling mystery, often with paranormal connotations.
Thus a strange object in the sky becomes a flying saucer; a mangy dead coyote becomes a chupacabra; and a deformed or sick child’s skull becomes an alien hybrid. Science fiction speculation is fun, but should not eclipse the real science and significance of these stories; truth is often stranger — and more interesting — than fiction.