"Archaeological evidence suggests that humans adopted new ways of processing food during the Neolithic which included the use of grinding stones and cooking in ceramic vessels (Larsen 2006; Meller et al. 2009). This is supported in Neolithic samples by a pattern of decreased skull size and shape and dental microwear evidence (Larsen 2006; Sardi et al. 2004). Bone responds to high amounts of physical activity and stress by increasing in mass (Larsen 2006: 16). Paleolithic hunter-gatherers likely had larger skulls than Neolithic peoples due to their more mobile and active lifestyle (Sardi et al. 2004). "It is accepted that masticatory forces regulate craniofacial growth and the stress is mainly due to the food consistency that causes variations in the mastication movement" (Sardi et al. 2004: 141). This means that facial structures are suited to individual chewing needs. When new preparation and processing methods were introduced, foods became softer and easier to chew. Over time this change in masticatory function contributed to an overall "gracilization" of the human skull and resulted in a smaller human face with reduced jaws and teeth (Larsen 1991, 2006; Sardi et al. 2004)."