[Quantitative study of encephalic components in 3 tinamid species, with an ecoethological approach (birds:...

The encephalon of three tinamids: Eudromia elegans, Nothura maculosa, and Rhynchotus rufescens are quantitatively analyzed. Both relative volumes and cerebral indexes are calculated for eleven encephalic components. Results are discussed from an eco-etiological approach. The relative size of encephalic components in Eudromia, Rhynchotus, and Nothura indicate a close relationship among brain components and some behavioral patterns and the environment. Marked differences in the cerebral organization of these tinamid genera are not evident. A greater development of the wulst and low values of olfactory bulbs suggest that Eudromia and Rhynchotus are progressive species. Nothura is considered primitive.