LAUSR

The economic anatomy for Rheidae (Class: Birds) which includes the calculation of the Modified General Utility Index (MGUI) and its component indexes: Meat Utility Index (MUI), Marrow Index (MI), White Grease Index (WGI), and General Utility Index (GUI) are presented in this paper. In addition, I describe the methodology implemented to generate each index and discuss these results, applying them to an archeofaunal setting. The results show net values of meat utility, which are associated to the anatomical portions of the appendicular skeleton; a high grease index, which is associated to the axial portions (mainly pelvis, sacrum, and sternum); and a high marrow index in the tibiotarsus and tarsometatarsus. The correlation that exists between the Economic Utility Index and the Structural Bone Density Index shows an equifinality problem. Finally, I compare the Utility Index for other ratites built with the purpose of giving an analogy for all the species that constitute this group of birds.