the second with another 5 subbasins form subhumid environments
We analyzed the avifauna of 26 subbasins of the Sierra Madre del Sur biotic province and their biogeographical relationships applying a parsimony analysis of endemicity (PAE). Based on the distributional information of the species obtained freom the Atlas de las ayes de Mexico and published literature, we built a data matrix for 26 subbasins and 437 species. The single cladogram obtained suggests the existence of three groups of subbasins:the first with 5 subbasins freom arid environments, geographically located in northsoutheastern Oaxaca
and the third one with the remaining subbasins, freom humid and environmentally more complex habitats.