Homo sapiens lack the digestive apparatus of ruminants that allow digestion of grasses. We lack the continuously growing teeth that resist the abrasive effect of phytoliths, the sand-like particles in grass blades; we lack the capacity to produce 100 liters of saliva per day; we lack a four compartment stomach that houses unique organisms that express the enzyme cellulase; we lack a spiral colon also housing unique microorganisms to digest the components of grass. We are a non-grass consuming species.