Ancient graves unearthed in the southwestern United States and northwestern Mexico indicate that the regions were places of violent feuds, said James Watson, a bioarchaeologist at the University of Arizona. His latest research that examined a series of unnatural burial sites between 2100 B.C. and 50 A.D. has been published in the journal Current Anthropology. The burials showed evidence of a brutal end where the skeletal remains included projectile points and broken bones, which led Watson to believe that it was a shooting death.

Deposited or splayed on the ground in an awkward manner, it was apparent they were not given the customary burial treatment. The burials also did not have other traditional funeral features, which would have been noticed had the bodies been laid to rest by family members. The dead did not receive reverential treatment, and their bodies were thrown around haphazardly and, in some cases, sustained post-mortem injuries in addition to the already violent death.

A common theory in the area where Watson works is that these bodies belonged to people accused of practicing witchcraft. However, since the cadavers were not mutilated in the way witches' historically were, he offered a different explanation. These bodies were possibly victims of family or blood feuds at a time when people were witnessing some serious pains, argued Watson in his paper. He also stated that the violence may have become ingrained or enculturated in some communities.

Behind the brutal handling of corpses, Watson uses the costly signaling theory to give reasons behind the cruel post-mortem treatment. According to him, these violent killings followed by sacrilegious burials point out to the fact of power and dominance in the era. Even though his work purely focuses on violence that took place thousands of years ago, he suggests that this theory is applicable in the violence of the present day like police shootings and murders.