US Geological Survey


Date of this Version



Published in Ornithological Monographs (2010) No. 67: 172-175. DOI: 10.1525/om.2010.67.1.172.


The 14 papers in this monograph represent the first broad-based evaluation of avian subspecies in decades and one of few, if any, multifaceted treatments of subspecies for any taxon. As such, there are multiple points of agreement and disagreement. Most authors consider the concept of subspecies a valid taxonomic category for units below the species level. All authors point to the need to reexamine taxa with modern methods to confirm their identity as subspecies. All authors also agree that the best approach to recognizing a subspecies is to include multiple characters (e.g., an mtDNA study alone will not suffice). However, issues regarding the reconciliation of data sets in which we expect evolutionary rates to differ, how various methods are implemented and compared, and the statistical analyses used have not been resolved. We conclude by calling for renewed interest in examining avian subspecies that have not had modern approaches applied to their classification. Each species evaluated will add to an improved understanding of avian diversity and its generation and will be a significant contribution to conservation.