As time moved along, the significance of the trophy heads transformed into a more outwardly aggressive practice. Between AD 450-750, the Nasca began collecting the heads of their enemies, while continuing the practice of gathering their ancestor’s heads. The pressure for resources from other tribes as well as the environmental pressures of the area might have encouraged the transformation of the trophy head’s significance. A drought occurred in AD 560 that then lasted for the next forty years, increasing the scarcity of resources in the area to astronomical levels. The struggle for fertility in the area, only increased due to this drought. In addition to the drought, if it was due to the resource scarcity or territory expansion, the appearance of the Wari and Tirwanaku tribes led to a higher tendency for warfare. Whether due to the presence of the other tribes or the increased competition for resources, the Nasca began collecting the heads of enemies as well as the heads of their ancestor.
There is a different culture existing in Ethiopia called the Surma communities that can be compared to the Nasca drought in the early to late stages of their culture. Young Surma men had ritual violence against other young Surma men. It is an area that has a lower percentage of women existing in the area. Women, like water to the Nasca, are scarce resources in the area. Both men and women are necessary for reproduction; reproduction is necessary for their survival. The Nasca became outwardly aggressive towards the other tribes of the area to increase their likelihood of gaining access to the few assets of water. Similarly, the Surma men use ritual violence in the form of stick fighting to increase their likelihood of gaining access to the few women of the area. The Surma men do not engage in this practice of ritual violence, unless other Surma women are present (Abbink). Similarly, the Nasca did not need to become outwardly aggressive until the 40-year drought threatened their survival. They did not react the aggressive stage until their resources were endangered.
Abbink, Jon. 1999, Ritual, and Reproduction: Culture and Context in Surma Dueling. Ethnography. 38 (3):227-242, University of Pittsburgh.
